1. A sprinkler assembly comprising:

a fire protection sprinkler having a body defining an inlet and an outlet with a passageway extending between the inlet and the outlet along a longitudinal axis, a deflector supported by the body and spaced from the outlet, the body having an outer encasing surface surrounding at least a portion of the passageway having an axial length in the direction of the longitudinal axis to define a first contact zone;

an escutcheon having a receiver and a rim surrounding the fire protection sprinkler to define an aperture between the receiver and the sprinkler, the receiver having a surface defining a second contact zone; and

a push-to-connect fitting including:

a tubular member with an end for connection to a pipe, the tubular member including an exterior surface and an inner surface, the inner surface defining an internal conduit that receives the body of the sprinkler;

a seal member and a retaining ring disposed within the internal conduit, the seal member forming a fluid tight seal about the first contact zone with the retaining ring engaged in a grip about the first contact zone to form an adjustable seal and grip about the outer encasing surface of the body of the sprinkler along the first contact zone; and

a releasing member that translates with respect to the tubular member to disengage the grip of the retaining ring about the first contact zone, the second contact zone of the escutcheon translating with respect to the tubular member to define an adjustable deflector-to-rim distance between the rim of the escutcheon and the deflector of the sprinkler.

2. The sprinkler assembly of claim 1, wherein the receiver of the escutcheon has an inner surface defining the second contact zone is in sliding surface contact with a portion of a peripheral surface of the releasing member.

3. The sprinkler assembly of claim 1 , wherein the receiver of the escutcheon has an outer surface defining the second contact zone in in contact with a support cup disposed about the sprinkler body.

4. The sprinkler assembly of claim 3, wherein the retaining ring includes a plurality of prongs radially disposed about a base to grip the sprinkler body, the releasing member including an inner wall defining a central opening for receipt of the sprinkler body, the releasing member being translatable with respect to each of the sprinkler body and the fitting such that the inner wall contacts the retaining ring to splay the plurality of prongs and release the grip about the sprinkler body.

5. The sprinkler assembly of claim 4, wherein the releasing member includes an outer wall circumferentially spaced about the inner wall, the escutcheon being in adjustable supporting surface contact engagement with the outer wall.

6. The sprinkler assembly of claim S, wherein the outer wall of the releasing member and the receiver of the escutcheon are in sliding surface contact engagement for adjustment of the deflector-to-rim distance.

7. The sprinkler assembly of any one of claims 4-6, further comprising a resistance member to resist relative translation between the releasing member and the tubular member.

8. The sprinkler assembly of claim 1 , wherein the releasing member traverses the aperture and is in supporting contact with the receiver.

9. The sprinkler assembly of claim 1, further comprising a supporting cup disposed about the sprinkler body, the escutcheon being engaged with the supporting cup.

10. The sprinkler assembly of claim 9, wherein the supporting cup has a central opening disposed over the sprinkler body such that the supporting cup circumscribes the sprinkler, the receiver including a projection engaged with an inner surface of the support cup, the supporting cup having a plurality of apertures overlaid by the releasing member, Uie releasing member being accessible through the plurality of apertures to adjust the fluid tight seal and grip about the sprinkler body and the deflector-to-rim distance.

11. The sprinkler assembly of claim 10, wherein the retaining ring includes a plurality of prongs radially disposed about a base to grip the sprinkler body, the releasing member including an inner wall defining a central opening for receipt of the sprinkler body, the releasing member being translatable with respect to each of the sprinkler body and the fitting so that the inner wall contacts the retaining ring and splays the plurality of prongs and releases the grip about the sprinkler body. 12. The sprinkler assembly of claim 11, wherein the releasing member includes an outer wall circumferentially spaced about the inner wall, the inner wall being disposed in the internal conduit of the tubular member, and the outer wall engaged with a peripheral surface of the tubular member to secure the releasing member to the tubular member.

13. The sprinkler assembly of claim 12, wherein the peripheral surface includes a groove, the outer wail including a projection engaged within the groove.

14. The sprinkler assembly of claim 13, wherein the push-to-connect fitting includes a first end and a second end, the second end including an annular flange formed about the second end of the fitting with the groove formed about a peripheral surface of the annular flange. 15. The sprinkler assembly of claim 14, wherein the groove defines a groove height and an amount of axial of relative translation between the tubular member and the releasing member.

16. The sprinkler assembly of claim 15, wherein the inner and outer wall define a channel therebetween to house the annular flange, a resisting element disposed in the channel to resist the relative translation between the releasing member and the tubular member.

17. The sprinkler assembly of any one of claims 9-16, further including a cover coupled to the rim of the escutcheon by a thermally responsive material.

18. The sprinkler assembly of claims 1-17, wherein the connection end of the tubular member is disposed within a pipe fitting receptacle. 19. A method of providing fire sprinkler protection, the method comprising:

providing a fire protection sprinkler having a body defining an inlet and an outlet with a passageway extending between the inlet and the outlet along a longitudinal axis, a deflector supported by the body and spaced from the outlet, the body having an outer encasing surface surrounding at least a portion of the passageway having an axial length in the direction of the longitudinal axis to define a first contact zone;

axially translating the sprinkler along the first contact zone within a push-to- connect fitting, the push-to-connect fitting including: a tubular member with an end for connection to a pipe, the tubular member including an exterior surface and an inner surface, the inner surface defining an internal conduit that receives the body of the sprinkler;

a seal member and a retaining ring disposed within the internal conduit, the seal member forming a fluid tight seal about the first contact zone with the retaining ring engaged in a grip about the first contact zone to form an adjustable seal and grip about the outer encasing surface of the body of the sprinkler along the first contact zone;

a releasing member that translates with respect to the tubular member to disengage the grip of the retaining ring about the first contact zone; and

axially translating an escutcheon having a receiver and a rim surrounding the fire protection sprinkler, the receiver defining a second contact zone for adjusting a deflector-to-rim distance between the rim of the escutcheon and the deflector of the sprinkler.

20. A recessed sprinkler assembly comprising:

a fire protection sprinkler having a body defining an inlet and an outlet with a passageway extending between the inlet and the outlet along a longitudinal axis, a deflector supported by the body and spaced from the outlet, the body having an outer encasing surface surrounding at least a portion of the passageway;

an escutcheon having a receiver and a rim, the receiver surrounding the fire protection sprinkler to define an annular aperture between the receiver and the sprinkler, and a push-to-connect fitting including:

a tubular member with an end for connection to a pipe, the tubular member including an exterior surface and an inner surface, the inner surface defining an internal conduit with the body of the sprinkler received in the internal conduit; a seal member and a retaining ring disposed within the internal conduit, the seal member forming a fluid tight seal about the outer encasing surface of the sprinkler body, the retaining ring engaged in a grip about the outer encasing surface of the body; and

a releasing member that translates with respect to the tubular member to disengage the grip of the retaining ring about the outer encasing surface of the body, the releasing member having a portion that radially traverses the aperture and contacts the receiver of the escutcheon.

21. The recessed sprinkler assembly of claim 20, wherein the traversing portion of the releasing member circumscribes the longitudinal axis to conceal the pipe connection end of the tubular member.

22. The recessed sprinkler assembly of claim 20, wherein the escutcheon has a first end and a second end, the rim formed at the second end with the releasing member located between the first and the second end. 23. The recessed sprinkler assembly of any one of claims 20-22, wherein the releasing member is coupled to the exterior surface of the tubular member, the exterior surface of the tubular member including a circumferential groove and the releasing member including an annular projection engaged within the circumferential groove.

24. The recessed sprinkler assembly of claim 23, wherein the tubular member includes a first end and a second end, the second end including an annular flange formed about the second end of the fitting with the groove formed about a peripheral surface of the annular flange.

25. The recessed sprinkler assembly of claim 24, wherein the groove defines a groove height and an amount of axial of relative translation between the tubular member and the releasing member.

26. The recessed sprinkler assembly of claim 20, wherein the releasing member includes an inner wall disposed within the conduit of the tubular member and an outer wall that contacts the receiver of the escutcheon, the traversing portion extending between (he inner and outer wall.

27. The recessed sprinkler assembly of claim 26, wherein the tubular member includes an annular flange, the inner wall of the releasing member defines a central opening axially aligned with the internal conduit of the tubular member, the outer wall circumscribing the inner wall of the releasing member to define a channel therebetween to house the annular flange of the tubular member.

28. The recessed sprinkler assembly of claim 27, further including a resisting element disposed in the channel to control relative translation between the releasing member and the tubular member.

29. The recessed sprinkler assembly of claim 26, wherein the inner wall defines an internal diameter and the outer wall defines an outer diameter, a ratio of outer diameter-to- inner diameter being 2:1.

30. The recessed sprinkler assembly of claim 29, wherein the outer encasing surface of the sprinkler body defines a maximum diameter of the sprinkler body, the internal diameter of the inner wall releasing member being greater than the maximum diameter, the internal diameter of the releasing member being greater than 0.9 inches.

31. The recessed sprinkler assembly of claim 20, wherein the releasing member and receiver of the escutcheon are in a surface contact engagement such that the releasing member supports the escutcheon to allow the escutcheon to axially translate relative to the releasing member. 32. The recessed sprinkler assembly of claim 31, wherein the retaining ring includes a plurality of prongs radially disposed about a base to grip the sprinkler body, the releasing member including an inner wall defining a central opening for receipt of the sprinkler body, the releasing member being translatable with respect to each of the sprinkler body and the tubular member such that the inner wall contacts the retaining ring to splay the plurality of prongs and release the grip about the sprinkler body.

33. The recessed sprinkler assembly of claim 32, wherein the releasing member includes an outer wall circumferentially spaced about the inner wall, the receiver of the escutcheon being in adjustable supporting surface contact engagement with the outer wall.

34. The recessed sprinkler assembly of claim 33, wherein the outer wall of the releasing member and the receiver of the escutcheon are in sliding surface contact engagement for adjustment of a distance between the deflector of the sprinkler and the rim of the escutcheon.

35. The recessed sprinkler assembly of claim 34, further including a resistance member between the inner and outer walls to control the relative translation between the releasing member and the tubular member. 36. The recessed sprinkler assembly of claim 33, wherein the outer wall is engaged with a peripheral surface of the tubular member, the peripheral surface including a groove, the outer wall including a projection engaged within the groove.

37. The recessed sprinkler assembly of any one of claims 20-36, wherein the push-to- connect fitting includes a first annular seat member and a second annular seat member axially spaced apart along the conduit to define a gap region therebetween; the seal member seated and the retaining ring disposed in the gap region, the seal member being seated against the first annular seat member and the retaining ring seated against the second seat member.

38. The recessed sprinkler assembly of any one of claims 20-37, further comprising a pipe fitting disposed about the tubular member.

39. The recessed sprinkler assembly of claim 38, wherein an annular aperture between the tubular member and the receiver houses an end of the pipe fitting. 40. The recessed sprinkler assembly of claim 38, wherein the pipe fitting is any one of an elbow fitting, a tee fitting.

41. The recessed sprinkler assembly of claim 40, wherein the pipe fitting is a tee fitting having axially aligned outlets and the recessed sprinkler assembly includes two escutcheons each disposed in the one of the axially aligned outlets, each escutcheon having a push-to- connect fitting engaged within a receiver of the escutcheon to provide a back-to-back arrangement

42. The recessed sprinkler of any one of claims 20-40, wherein the sprinkler is an automatic sprinkler having a thermally responsive seal assembly to control fluid discharge from the outlet. 43. A method of recessed sprinkler installation comprising:

centering a sprinkler connected to a tubular member of a push-to-connect fitting within an annular receiver of an escutcheon; and traversing an annular aperture between the fitting and the annular receiver with a releasing member of the push-to-connect fitting.

44. The method of any one of claims 43, wherein the centering includes receiving the sprinkler in an internal conduit of the tubular member of the push-to-connect fitting, further comprising coupling the releasing member to the tubular member of the push-to-connect fitting.

45. The method of claim 44, wherein the traversing includes placing an outer wall of the releasing member in surface contact engagement with the receiver of the escutcheon and the centering includes inserting an inner wall of the releasing member into the internal conduit of the tubular member, the inner wall being radially inward of the outer wall.

46. The method of claim 45, further comprising coupling the outer wall of the releasing member to a peripheral circumferential groove formed in the tubular member.

47. The method of any one of claims 43-46, further includes axially locating the escutcheon about the releasing member and controlling relative axial translation between the tubular member and the releasing member with a resistance member disposed between the tubular member and the releasing member.

48. A method of providing a recessed sprinkler, the method comprising:

providing a sprinkler assembly including:

a fire protection sprinkler having a body defining an inlet and an outlet with a passageway extending between the inlet and the outlet along a longitudinal axis, a deflector supported by the body and spaced from the outlet, the body having an outer encasing surface surrounding at least a portion of the passageway; an escutcheon having a receiver and a rim, the receiver surrounding the fire protection sprinkler to define an annular aperture between the receiver and the sprinkler, and

a push-to -connect fitting including:

a tubular member with an end for connection to a pipe, the tubular member including an exterior surface and an inner surface, the inner surface defining an internal conduit that receives the body of the sprinkler;

a seal member and a retaining ring disposed within the internal conduit, the seal member forming a fluid tight seal about the encasing surface, the retaining ring engaged in a grip about the outer encasing surface of the body; and

a releasing member that translates with respect to the tubular member to disengage the grip of the retaining ring about the outer encasing surface of the body, the releasing member having a portion that radially traverses the aperture and contacts the receiver of the escutcheon; and

distributing the sprinkler assembly for protection of an area separated from a confined area by a barrier, the distributing including distributing the sprinkler assembly for recessed installation with connection of the push-to-connect fitting to a firefighting fluid supply pipe located in the confined area.

49. The method of claim 48, wherein providing the sprinkler assembly includes providing the tubular member of the push-to-connect fitting affixed within a pipe supply fitting.

50. The method of claim 48, wherein providing the sprinkler assembly includes providing two sprinkler assemblies each having a sidewall deflector with the push-to-connect fitting affixed to axially aligned receptacles of a tee fitting to define a back-to-back arrangement.

51. The method of claim 48, wherein providing the sprinkler assembly includes adjustably supporting the escutcheon about the releasing member with surface contact engagement between the receiver of the escutcheon and an outer wall of the releasing member. 52. A recessed push-to-connect fitting:

an escutcheon having a receiver and a rim; and

a push-to-connect fitting including:

a tubular member with an end for connection to a pipe, the tubular member including an exterior surface and an inner surface, the inner surface defining an internal conduit for receipt of a fire protection sprinkler;

a seal member and a retaining ring disposed within the internal conduit for forming a fluid tight sealing grip about the fire protection sprinkler; and

a releasing member that translates with respect to the tubular member to disengage the grip of the retaining ring about the fire protection sprinkler, the receiver of the escutcheon supported about the releasing member to define an annular aperture between the tubular member and the receiver, the releasing member having a portion that radially traverses the annular aperture.

53. A sprinkler assembly comprising:

a fire protection sprinkler having a body defining an inlet and an outlet with a passageway extending between the inlet and the outlet along a longitudinal axis, a deflector supported by the body and spaced from the outlet, the body having an outer encasing surface surrounding at least a portion of the passageway; and

a push-to-connect fitting including: a tubular member with an end for connection to a pipe, the tubular member including a peripheral surface and an inner surface, the inner surface defining an internal conduit that receives the body of the sprinkler;

a seal member and a retaining ring disposed within the internal conduit, the seal member forming a fluid tight seal about the outer encasing surface of the sprinkler body, the retaining ring engaged in a grip about the outer encasing surface of the body; and

a releasing member that translates with respect to the tubular member to disengage the grip of the retaining ring about the outer encasing surface of the body, the releasing member being secured to the peripheral surface of the tubular member.

54. The sprinkler assembly of claim 53, wherein the tubular member includes a first end and a second end, the second end including an annular flange with a circumferential groove along an exterior surface of the annular flange.

55. The sprinkler assembly of claim 54, wherein the releasing member includes an annular projection engaged within the circumferential groove.

56. The sprinkler assembly of claim 55, wherein the circumferential groove defines a groove height and an amount of axial of relative translation between the tubular member and the releasing member.

57. The sprinkler assembly of any one of claims 53-56, wherein the push-to-connect fitting includes a first annular seat member and a second annular seat member axially spaced apart along the internal conduit to define a gap region therebetween; the seal member seated and the retaining ring disposed in the gap region with the seal member being seated against the first annular seat member and the retaining ring seated against the second seat member.

58. The sprinkler assembly of any one of claims 53-57, further comprising a pipe fitting disposed about the tubular member.

59. The sprinkler assembly of claim 58, wherein the pipe fitting is a tee fitting having axially aligned outlets and the sprinkler assembly includes two escutcheons each disposed in the one of the axially aligned outlets, each escutcheon having a push-to-connect fitting engaged within a receiver of the escutcheon inserted in one of the axially aligned outlets and centered within an annular wall of an outer escutcheon member to provide a back-to-back arrangement.

60. The sprinkler assembly of any one of claims 53-59, wherein the releasing member includes an inner wall disposed in the internal conduit, the releasing member including an outer wall circumferentially spaced about the inner wall, the outer wall having an annular projection engaged with the peripheral surface of the tubular member.

61. The sprinkler assembly of claim 60, wherein the inner and outer walls define an annular channel in between for receiving and end of the tubular member and housing a resisting member to resist the axial translation between the tubular member and the releasing member.

62. The sprinkler assembly of claim 60, wherein the tubular member includes a first end and a second end, wherein the first end of the tubular member defines a first diameter and the outer wall of the releasing member defines a second diameter, a ratio of the second diameter to the first diameter is 1.2:1.

63. The sprinkler assembly of claim 53, wherein the tubular member includes a first end and a second end, wherein the second end is larger than the first end of the tubular member, the first end being affixed within a receptacle of fluid supply pipe fitting with the second end forming a flange disposed outside the pipe fitting.

64. The sprinkler assembly of any one claims 53-63, wherein the tubular member includes a first annular seat and a second annular seat spaced apart within the internal conduit to define a gap region therebetween for housing the seal member and the retaining ring.

65. The sprinkler assembly of any one of claims 53-64, wherein the sealing member includes at least two separate sealing surfaces integral with one another with the retaining ring including a base with a plurality of prongs angularly disposed about the base.

66. The sprinkler assembly of any one claims 53-65, further comprising a resistance member to control the relative translation between the releasing member and the tubular member.

67. The sprinkler assembly of claim 53, wherein the body defines a body length ranging from 1.5-2.0 inches.

68. The sprinkler assembly of 53, wherein the passageway of the sprinkler body includes a first portion adjacent the inlet having a constant internal diameter and a second portion adjacent the outlet having a variable diameter that narrows in a direction of flow from inlet- to-outlet, the passageway defining a total passageway ranging from 1.5-2.0 inches.

69. The sprinkler assembly of claim 68, wherein the first portion has an axial length to define a body length-to-axial length ratio of 2: 1 -3 : 1. 70. The sprinkler assembly of claim 68, wherein the second portion defines a taper defined by an included angle that ranges from 7° to 8°.

71. The sprinkler assembly of claim 70, further comprising a third portion between the first and second portion defining a variable diameter that narrows in the direction of flow, the third portion defined by an included angle that ranges from 15° to 20°.

72. The sprinkler assembly of claim 53, wherein the encasing surface defines an body diameter 0.9- 1.0 inch.

73. The sprinkler assembly of claim 53, wherein the releasing member has an end face with a central opening axially aligned with the internal conduit with the sprinkler body, the end face being axially spaced from the seal member to define a mechanism length of the push-to-connect fitting, the ratio of mechanism length-to- minimum internal diameter of the retaining ring ranging from 0.5:1-0.6:1.

74. The sprinkler assembly of claim 53, wherein the push-to-connect fitting has a first end and a second end to define an overall axial height, the second end of the push-to-connect fitting having an end face with a central opening axially aligned with the internal conduit of the tubular member, the end face being axially spaced from the seal member to define a mechanism length of the push-to-connect fitting, the ratio of mechanism length-to-overall axial height being less than 0.4:1.

75. The sprinkler assembly of any one of claims 53-57 , further comprising an escutcheon having a receiver and a rim, the receiver being disposed about the releasing member to form an annular aperture between the receiver and the fire protection sprinkler, the releasing member having a peripheral surface in surface contact engagement with the receiver such that the releasing member traverses the annular aperture.

76. The sprinkler assembly of claim 75, wherein the traversing portion of the releasing member circumscribes the longitudinal axis to conceal the pipe connection end, the escutcheon having a first end and a second end, the rim formed at the second end with the releasing member located between the first and the second end. 77. The sprinkler assembly of claim 53, further comprising:

a support cup having a central hole with a plurality of openings about the central hole, the support cup disposed over the sprinkler body such that the releasing member overlays the plurality of openings;

an escutcheon engaged with the support cup, the escutcheon having a receiver and a rim; and

a cover coupled to the rim by a thermally responsive material to conceal the deflector.

78. The sprinkler assembly of any one of claims 53-77, wherein the sprinkler is an automatic sprinkler having a thermally responsive seal assembly to control fluid discharge from the outlet.

79. A method of push-to-connect fitting for a fire protection sprinkler, the method comprising:

forming a fluid tight seal and grip about a sprinkler body of a fire protection sprinkler in an internal conduit of a push-to-connect fitting extending along a longitudinal axis; and

axially translating a releasing member secured to a peripheral surface of the push-to-connect fitting along the longitudinal axis to release the fluid tight seal and grip about the sprinkler body.

80. The method of claim 79, wherein axially translating the releasing member includes engaging the releasing member in a peripheral circumferential groove formed about the peripheral surface of the push-to-connect fitting.

81. The method of claim 80, wherein axially translating the releasing member includes locating an inner wall within the internal conduit of the push-to-connect fitting and the engaging includes engaging an outer wall of the releasing member circumferentially spaced about the inner wall within the groove.

82. The method of claim 81, wherein forming the fluid tight grip seal includes seating a seal member and a retaining ring between a first annular seat member and a second seat member, wherein locating the inner wall includes freely centering the inner wall within the second seat member to contact the retaining ring upon axially translating the releasing member.

83. The method of claim 81, further comprising supporting a mounting escutcheon about the outer wall so as to define an annular aperture between the sprinkler and the mounting escutcheon, the releasing member traversing the annular aperture.

84. The method of claim 79, further comprising:

disposing the sprinkler through a central hole of a support cup having a plurality of openings about disposed about the central hole, the support cup circumscribing the sprinkler to define an annular aperture therebetween; .

engaging a mounting escutcheon assembly to the support cup to conceal the sprinkler, the support cup having an annular receiver wall and a rim with a flat plate coupled to the rim by a thermally responsive material, wherein forming the fluid tight seal locates the support cup such that the releasing member overlays the plurality of openings of the support cup.

85. The method of claim 84, wherein axially translating the releasing member includes accessing the releasing member through the annular aperture and the plurality of openings. 86. The method of any one of claims 79-85, further comprising distributing the sprinkler for protection of an area separated from a confined area by a barrier, the distributing including distributing the sprinkler assembly for connection to a firefighting fluid supply pipe located in the confined area with the push-to-connect fitting.

87. The method of claim 86, wherein the distributing includes providing a tubular member of the push-to-connect fitting affixed within a pipe supply fitting.

88. The method of claim 87, wherein providing the sprinkler includes providing two sprinkler assemblies each having a sidewall deflector with the push-to-connect fitting affixed to axially aligned receptacles of a tee fitting to define a back-to-back arrangement.

89. The method of claim 87, wherein providing the sprinkler assembly includes adjustably supporting an escutcheon about the releasing member with surface contact engagement between the receiver of the escutcheon and an outer wall of the releasing member.

90. A sprinkler assembly comprising:

a fire protection sprinkler having a body defining an inlet and an outlet with a passageway extending between the inlet and the outlet along a longitudinal axis, a deflector supported by the body and spaced from the outlet, the body having an outer encasing surface surrounding at least a portion of the passageway; and a push-to-connect fitting including:

a tubular member with an exterior surface and an inner surface defining an internal conduit extending along a longitudinal axis with the sprinkler body located in the internal conduit;

a seal member and a retaining ring disposed within the internal conduit, the retaining ring defining a minimum internal diameter, the seal member forming a fluid tight seal about the outer encasing surface of the sprinkler body, the retaining ring engaged in a grip about the outer encasing surface of the body; and

a releasing member coupled to the tubular member that translates with respect to the tubular member to disengage the retaining ring grip about the encasing surface of the body, the releasing member having an end face with a central opening axially aligned with the internal conduit, the end face being axially spaced from the seal member to define a mechanism length of the push-to-connect fitting, a ratio of mechanism length-to-minimum internal diameter of the retaining ring ranging from 0.5:1-0.6:1. 91. A sprinkler assembly comprising:

a fire protection sprinkler having a body defining an inlet and an outlet with a passageway extending between the inlet and the outlet along a longitudinal axis, a deflector supported by the body and spaced from the outlet, the body having an outer encasing surface surrounding at least a portion of the passageway; and

a push-to-connect fitting having a first end, a second end defining an overall axial height from the first end to the second end, the push-to-connect fitting including:

a tubular member with an exterior surface and an inner surface defining an internal conduit extending along a longitudinal axis with the sprinkler body located in the internal conduit; a seal member and a retaining ring disposed within the internal conduit, the seal member forming a fluid tight seal about the outer encasing surface of the sprinkler body, the retaining ring engaged in a grip about the outer encasing surface of the body; and

a releasing member that translates with respect to the tubular member to disengage the retaining ring grip about the encasing surface of the body, the second end of the push-to-connect fitting having an end face with a central opening axially aligned with the internal conduit, the end face being axially spaced from the seal member to define a mechanism length of the push-to-connect fitting, the ratio of mechanism length-to-overall axial height being less than 0.4:1.

92. The sprinkler assembly of any one of claims 90-91, wherein the sprinkler body defines a body length and the passageway of the sprinkler body defines a nominal K-factor, a K-factor-to-body length ratio ranging from 3.3:1 to 1.3:1.

93. The sprinkler assembly of claim 92, wherein the body length ranges from 1.5-2.0 inches.

94. The sprinkler assembly of any one of claims 90-91, wherein the passageway of the sprinkler body includes a first portion adjacent the inlet having a constant internal diameter and a second portion adjacent the outlet having a variable diameter that narrows in a direction of flow from inlet-to-outlet, the passageway defining a total passageway ranging from 1.5-2.0 inches.

95. The sprinkler assembly of claim 94, wherein the first portion has an axial length to define a body length-to-axial length ratio of 2: 1 -3 : 1.

96. The sprinkler assembly of claim 95, wherein the second portion defines a taper defined by an included angle that ranges from 7° to 8°.

97. The sprinkler assembly of claim 96, further comprising a third portion between the first and second portion defining a variable diameter that narrows in the direction of flow, the third portion defined by an included angle that ranges from 15° to 20°.

98. The sprinkler assembly of any one of claims 90-91, wherein the outer encasing surface of the sprinkler body defines an body diameter ranging from 0.9-1.0 inch.

99. The sprinkler assembly of any one of claims 90-91, wherein the releasing member is coupled to the peripheral surface of the tubular member, the peripheral surface of the tubular member including a circumferential groove and the releasing member including an annular projection engaged within the circumferential groove.

100. The sprinkler assembly of claim 99, wherein the tubular member includes a first end and a second end, the second end including an annular flange formed about the second end of the fitting with the groove formed about the peripheral surface of the annular flange, the circumferential groove defining a groove height and the amount of axial of relative translation between the tubular member and the releasing member.

101. The sprinkler assembly of any one claims 90- 100, wherein the push-to-connect fitting includes a first annular seat member and a second annular seat member axially spaced apart along the internal conduit to define a gap region therebetween; the seal member seated and the retaining ring disposed in the gap region, the seal member being seated against the first annular seat member and the retaining ring seated against the second seat member.

102. The sprinkler assembly of any one of claims 90-101, further comprising a pipe fitting disposed about the tubular member, wherein the pipe fitting is any one of an elbow fitting or a tee fitting.

103. The sprinkler assembly of claim 102, wherein the pipe fitting is a tee fitting having axially aligned pipe ends, the recessed sprinkler assembly includes two escutcheons each disposed in the one of the axially aligned pipe ends, each escutcheon having a push-to- connect fitting engaged within a receiver of the escutcheon to provide a back-to-back arrangement.

104. The sprinkler assembly of any one claims 90-103, wherein the releasing member includes an inner wall disposed in the internal conduit of the tubular member and freely centered therein to release the sprinkler body upon axial translation of the releasing member, the releasing member including an outer wall circumferentially spaced from the inner wall having an projection engaged with the peripheral surface of the tubular member.

105. The sprinkler assembly of claim 104, wherein the inner and outer walls define an annular channel in between for housing an end of the tubular member and a resisting member to control the axial translation between the tubular member and the releasing member.

106. The sprinkler assembly of claim 105, wherein the tubular member includes an end for insertion in a pipe fitting, the insertion end defining a first diameter and the outer wall of the releasing member defining a second diameter, a ratio of the second diameter to the first diameter is 1.2:1.

107. The sprinkler assembly of any one of claims 90-91, wherein the tubular member includes a first end and a second end, wherein the second end is larger than the first end of the tubular member, the first end being affixed in a fluid supply pipe fitting with the second end forms an annular flange disposed outside the end of the pipe fitting.

108. The sprinkler assembly of any one claims 90- 107, wherein the sealing member including at least two separate sealing surfaces integrated with a sealing base with the retaining ring including a plurality of prongs angularly disposed about a retaining ring base.

109. The sprinkler assembly of any one of claims 90-108, further comprising an escutcheon having a receiver and a rim, the receiver being disposed about the releasing member to form an annular aperture between the receiver and the fire protection sprinkler, the releasing member having a peripheral surface in surface contact engagement with the receiver such that the releasing member traverses the annular aperture and contacts the receiver.

1 10. The sprinkler assembly of claim 109, wherein the traversing portion of the releasing member circumscribing the longitudinal axis to conceal the pipe connection end.

111. The sprinkler assembly of claim 110, wherein the escutcheon has a first end and a second end, the rim formed at the second end with the releasing member located between the first and the second end.

112. The sprinkler assembly of any one of claim 90-11 1, further comprising:

a support cup having a central hole with a plurality of openings about the central hole, the support cup disposed over the sprinkler body such that the releasing member overlays the plurality of openings;

an escutcheon engaged with the support cup, the escutcheon having a receiver and a rim; and a cover coupled to the rim by a thermally responsive material to

113. The recessed sprinkler of any one of claims 90-112, wherein the sprinkler is an automatic sprinkler having a thermally responsive seal assembly to control fluid discharge from the outlet.

114. A sprinkler connection fitting comprising:

a tubular member with an exterior surface and an inner surface defining an internal conduit extending along a longitudinal axis;

a seal member and a retaining ring disposed within the internal conduit; and a releasing member coupled to the tubular member that translates with respect to the tubular member, the releasing member having an end face with a central opening axially aligned with the internal conduit, the end face being axially spaced from the seal member to define a mechanism length of the push-to-connect fitting, the ratio of mechanism length-to-minimum internal diameter of the retaining ring ranging from 0.5:1-0.6:1. 115. The sprinkler connection fitting of claim 114, wherein the releasing member is coupled to the exterior surface of the tubular member, the exterior surface of the tubular member including a circumferential groove and the releasing member including an annular projection engaged within the circumferential groove.

116. The sprinkler connection fitting of claim 1 15, wherein the tubular member includes a first end and a second end, the second end including an annular flange formed about the second end of the fitting with the groove formed about a peripheral surface of the annular flange, the groove defining a groove height and an amount of axial of relative translation between the tubular member and the releasing member.

117. The sprinkler connection fitting of any one of claims 114-116, wherein the tubular member includes a first annular seat member and a second annular seat member axially spaced apart along the conduit to define a gap region therebetween; the seal member seated and the retaining ring disposed in the gap region, the seal member being seated against the first annular seat member and the retaining ring seated against the second seat member.

118. The sprinkler connection fitting of any one of claims 1 14- 117, further comprising a pipe fitting disposed about the tubular member, wherein the pipe fitting is any one of an elbow fitting, a tee fitting or a union.

119. The sprinkler connection fitting of claim 118, wherein the pipe fitting is a tee fitting having axially aligned pipe ends, the recessed sprinkler assembly includes two escutcheons each disposed in the one of the axially aligned pipe ends, each escutcheon having a push-to- connect fitting engaged within a receiver of the escutcheon to provide a back-to-back arrangement.

120. The sprinkler connection fitting of any one of claims 114-119, wherein the releasing member includes an inner wall disposed in the internal conduit of the tubular member and freely centered therein, the releasing member including an outer wall circumferentially spaced from the inner wall having an projection engaged with the peripheral surface of the tubular member.

121. The sprinkler connection fitting of claim 120, wherein the inner and outer walls define an annular channel in between for housing an end of the tubular member and a resisting member to control the axial translation between the tubular member and the releasing member.

122. The sprinkler connection fitting of claim 121, wherein the tubular member includes an end for insertion in a pipe fitting, the insertion end defining a first diameter and the outer wall of the releasing member defining a second diameter, the ratio of the second diameter to the first diameter is 1.2:1.

123. The sprinkler connection fitting of claim 114, wherein the tubular member includes a first end and a second end, wherein the second end is larger than the first end of the tubular member, the first end being affixed in a fluid supply pipe fitting with the second end forms an annular flange disposed outside the end of the pipe fitting.

124. The sprinkler connection fitting of any one of claims 114-123, wherein the sealing member including at least two separate sealing surfaces integrated with a sealing base with the retaining ring including a plurality of prongs angularly disposed about a retaining ring base.

125. A sprinkler assembly comprising:

a push-to-connect fitting including:

a tubular member with an exterior surface and an inner surface, the inner surface defining an internal conduit extending along a longitudinal axis for receipt of a sprinkler body to be axially aligned and located within the internal conduit;

a seal member and a retaining ring disposed within the internal conduit; and

a releasing member that translates with respect to the tubular member; and

a fire protection sprinkler inserted within the push-to-connect-fitting having a body received within the internal conduit of the tubular member and extending along the longitudinal axis, the sprinkler body defining a body length, the body having an outer encasing surface extending axially over at least a portion of the body length with the seal member forming a fluid tight seal about the encasing surface and the retaining ring engaged in a grip about the outer encasing surface of the body, the translation of the releasing member relative the tubular member disengaging the grip of the retaining ring, the body having an inlet and an outlet with a passageway extending along the longitudinal axis between the inlet and the outlet to define a nominal K-factor and K-factor-to-body length ratio ranging from

3.3:1 to 1.3:1, the fire protection sprinkler including a deflector supported by the body and spaced from the outlet. 126. The sprinkler assembly of claim 125, wherein when the tubular member is supplied with fire protection fluid, the inserted fire protection sprinkler discharges the fluid to define a rated K-factor that is at least 90% of the nominal K-Factor.

127. The sprinkler assembly of claim 125, wherein the body length ranges from 1.5-2.0 inches; 128. The sprinkler assembly of 127, wherein the passageway of the sprinkler body includes a first portion adjacent the inlet having a constant internal diameter and a second portion adjacent the outlet having a variable diameter that narrows in a direction of flow from inlet- to-outlet.

129. The sprinkler assembly of claim 128, wherein the first portion has an axial length to define a body length-to-axial length ratio of 2: 1 -3 : 1.

130. The sprinkler assembly of claim 128, wherein the second portion defines a taper defined by an included angle that ranges from 7° to 8°.

131. The sprinkler assembly of claim 128, further comprising a third portion between the first and second portion defining a variable diameter that narrows in the direction of flow, the third portion defined by an included angle that ranges from 15° to 20°.

132. The sprinkler assembly of claim 125, wherein the sprinkler body defines a body diameter 0.9- 1.0 inch.

133. The sprinkler assembly of claim 125, wherein the releasing member is coupled to the exterior surface of the tubular member, the exterior surface of the tubular member including a circumferential groove and the releasing member including an annular projection engaged within the circumferential groove. 134. The sprinkler assembly of claim 133, wherein the tubular member includes a first end and a second end, the second end including an annular flange formed about the second end of the tubular member with the groove formed about a peripheral surface of the annular flange, the groove defining a groove height and an amount of axial of relative translation between the tubular member and the releasing member. 135. The sprinkler assembly of any one of claims 125-134, wherein the tubular member includes a first annular seat member and a second annular seat member axially spaced apart along the conduit to define a gap region therebetween; the seal member seated and the retaining ring disposed in the gap region, the seal member being seated against the first annular seat member and the retaining ring seated against the second seat member. 136. The sprinkler assembly of claim 135, further comprising a pipe fitting disposed about the tubular member, wherein the pipe fitting is any one of an elbow fitting, a tee fitting or union.

137. The sprinkler assembly of claim 136, wherein the pipe fitting is a tee fitting having axially aligned outlets and the sprinkler assembly includes two escutcheons each disposed in the one of the axially aligned outlets, each escutcheon having a push-to-connect fitting engaged within a receiver of the escutcheon inserted in one of the axially aligned outlets and centered within an annular wall of an outer escutcheon member to provide a back-to-back arrangement.

138. The sprinkler assembly of any one of claims 125-137, wherein the releasing member includes an inner wall disposed in the internal conduit and freely centered in a central opening of the second annular seat to release the sprinkler body upon axial translation of the releasing member, the releasing member including an outer wall circumferentially spaced about the inner wall having a projection engaged with the exterior surface of the tubular member.

139. The sprinkler assembly of claim 138, wherein the inner and outer walls define an annular channel in between for receiving an end of the tubular member and housing a resisting member to resist the axial translation between the tubular member and the releasing member.

140. The sprinkler assembly of claim 139, wherein the tubular member includes a first end and a second end, wherein the first end of the tubular member defines a first diameter and the outer wall of the releasing member defines a second diameter, a ratio of the second diameter to the first diameter is 3 : 1.

141. The sprinkler assembly of claim 125, wherein the releasing member translates with respect to the tubular member to disengage the retaining ring grip about the encasing surface of the body, the releasing member having an end face with a central opening axially aligned with the internal conduit of the tubular member, the end face being axial ly spaced from the seal member to define a mechanism length of the push-to-connect fitting, the ratio of mechanism length-to-minimum internal diameter of the retaining ring ranging from 0.5:1-

0.6:1. 142. The sprinkler assembly of claim 125, wherein the push-to-connect fitting has a defined assembled height, the releasing member having an end face with a central opening axially aligned with the internal conduit of the tubular member, the end face being axially spaced from the seal member to define a mechanism length of the push-to-connect fitting, the ratio of mechanism length-to-overall axial height being less than 0.4:1. 143. The sprinkler assembly of claim 125, wherein the tubular member includes a first end and a second end, wherein the second end is larger than the first end of the tubular member, the first end being affixed in a fluid supply pipe fitting with the second end forms a flange disposed outside the supply pipe fitting.

144. The sprinkler assembly of any one claims 125-143, wherein the tubular member includes a first annular seat and a second annular seat spaced apart to define a gap region therebetween for housing the seal member and the retaining ring, the sealing member including at least two separate sealing surfaces integrated with a sealing base, the retaining ring including a base with a plurality of prongs angularly disposed about the base.

145. The sprinkler assembly of any one of claims 125-144, further comprising an escutcheon having a receiver and a rim, the receiver being disposed about the releasing member to form an annular aperture between the receiver and the fire protection sprinkler, the releasing member having a peripheral surface in surface contact engagement with the receiver such that the releasing member traverses the annular aperture and contacts the receiver.

146. The sprinkler assembly of any one of claim 145, wherein the traversing portion of the releasing member circumscribing the longitudinal axis to conceal the pipe connection end. 147. The sprinkler assembly of claim 145, wherein the escutcheon has a first end and a second end, the rim formed at the second end with the releasing member located between the first and the second end.

148. The sprinkler assembly of any one of claims 125-136, further comprising:

a support cup having a central hole with a plurality of openings about the central hole, the support cup disposed over the sprinkler body such that the releasing member overlays the plurality of openings;

an escutcheon engaged with the support cup, the escutcheon having a receiver and a rim; and

a cover coupled to the rim by a thermally responsive material to conceal the deflector.

149. The sprinkler assembly of any one of claims 125-148, wherein the sprinkler is an automatic sprinkler having a thermally responsive seal assembly to control fluid discharge from the outlet.

150. A method of fire sprinkler protection comprising:

providing a fire protection sprinkler having a body extending along a longitudinal axis defining a body length, the body having an outer encasing surface extending axially over at least a portion of the body length, the body having an inlet and an outlet with a passageway extending along the longitudinal axis between the inlet and the outlet to define a nominal K-factor and K-factor-to-body length ratio ranging from 3.3:1 to 1.3:1, the fire protection sprinkler including a deflector supported by the body and spaced from the outlet; and

providing a sprinkler assembly with the fire protection sprinkler assembled within a push-to-connect fitting including:

locating the sprinkler body within an internal conduit of a tubular member of the push-to-connect fitting;

forming a fluid tight seal along the encasing surface with a seal member of the push-to-connect fitting located within the internal conduit of the tubular member;

gripping the encasings surface with a retaining ring disposed within the internal conduit of the push-to-connect fitting; and

releasing the grip by translating a releasing member axially with respect to the tubular member.

151. The method of claim 150, providing the sprinkler assembly includes distributing the sprinkler assembly for protection of an area separated from a confined area by a barrier, the distributing including distributing the sprinkler assembly for connection to a firefighting fluid supply pipe located in the confined area with the push-to-connect fitting. 152. The method of claim 151, wherein providing the sprinkler assembly includes providing the tubular member of the push-to-connect fitting affixed within a pipe supply fitting for connection to the fluid supply pipe.

153. The method of claim 152, wherein providing the sprinkler assembly includes providing two sprinkler assemblies each having a sidewall deflector with the push-to-connect fitting affixed to axially aligned receptacles of a tee fitting to define a back-to-back arrangement. 154. The method of claim 150, wherein providing the sprinkler assembly includes adjustably supporting an escutcheon about the releasing member with surface contact engagement between a receiver of the escutcheon and an outer wall of the releasing member.

155. A sprinkler assembly comprising:

a fire protection sprinkler having a body defining an inlet and an outlet with a passageway extending between the inlet and the outlet along a longitudinal axis, a deflector supported by the body and spaced from the outlet, the body having an outer encasing surface surrounding at least a portion of the passageway;

a pipe fitting having a first pipe end for connection to a fluid supply pipe and at least a second pipe end with an internal flow path connecting the first and at least second pipe ends, each of the first and at least second pipe ends having an internal surface and a shoulder circumscribing the flow path to define a receptacle at the pipe end having an insertion depth; and

an insert push-to-connect fitting including:

a tubular member with an exterior surface and an inner surface, the inner surface defining an internal conduit that receives the body of the sprinkler;

a seal member and a retaining ring disposed within the internal conduit, the seal member forming a fluid tight seal about the outer encasing surface of the sprinkler body, the retaining ring engaged in a grip about the outer encasing surface of the body; and a releasing member that translates with respect to the tubular member to disengage the retaining ring grip about the encasing surface of the body,

the tubular member having a securement portion with the exterior surface of the securement portion of the tubular member defining a constant diameter over an axial length at least equal to the insertion depth, the exterior surface of the securement portion being in contact with and affixed to the inner surface of the at least second receptacle.

156. The sprinkler assembly of claim 155, wherein the tubular member includes a peripheral surface having a circumferential groove and the releasing member including an annular projection engaged within the circumferential groove to secure the releasing member to the tubular member.

157. The sprinkler assembly of claim 156, wherein the tubular member includes a first end and a second end, the second end including an annular flange formed about the second end of the tubular member with the circumferential groove along a peripheral surface of the annular flange. 158. The sprinkler assembly of claim 157, wherein the circumferential groove defines a groove height and an amount of axial of relative translation between the tubular member and the releasing member.

159. The sprinkler assembly of any one of claims 155-158, wherein the push-to-connect fitting includes a first annular seat member and a second annular seat member axially spaced apart along the conduit to define a gap region therebetween; the seal member seated and the retaining ring disposed in the gap region, the seal member being seated against the first annular seat member and the retaining ring seated against the second seat member.

160. The sprinkler assembly of claim 159, wherein the releasing member includes an inner wall disposed in the internal conduit and freely centered in a central opening of the second annular seat to release the sprinkler body upon axial translation of the releasing member, the releasing member including an outer wall circumferentially spaced from the inner wall having an projection engaged with an exterior surface of the tubular member.

161. The sprinkler assembly of claim 160, wherein the inner and outer walls define an annular channel in between for receiving an end of the tubular member and housing a resisting member to control the axial translation between the tubular member and the releasing member. 162. The sprinkler assembly of claim 160, wherein the tubular member includes a first end and a second end, wherein the first end of the tubular member defines a first diameter and the outer wall of the releasing member defines a second diameter, a ratio of the second diameter to the first diameter to is 1.2 : 1.

163. The sprinkler assembly of claim 155, wherein the tubular member includes a first end and a second end, wherein the second end is larger than the first end, the second end forms an annular flange disposed outside the at least second receptacle.

164. The sprinkler assembly of claim 155, a resistance member to control relative translation between the releasing member and the tubular member.

165. The sprinkler assembly of claim 155, wherein the sprinkler body defines a body length ranging from 1.5-2.0 inches.

166. The sprinkler assembly of 165, wherein the passageway of the sprinkler body includes a first portion adjacent the inlet having a constant internal diameter and a second portion adjacent the outlet having a variable diameter that narrows in a direction of flow from inlet- to-outlet. 167. The sprinkler assembly of claim 166, wherein the first portion has an axial length to define a body length-to-axial length ratio of 2:1-3:1.

168. The sprinkler assembly of claim 167, wherein the second portion defines a taper defined by an included angle that ranges from 7° to 8°.

169. The sprinkler assembly of claim 168, further comprising a third portion between the first and second portion defining a variable diameter that narrows in the direction of flow, the third portion defined by an included angle that ranges from 15° to 20°.

170. The sprinkler assembly of claim 155, wherein the outer encasing surface of the sprinkler body defines a body diameter 0.9-1.0 inch.

171. The sprinkler assembly of claim 155, wherein the releasing member has an end face with a central opening axially aligned with the internal conduit of the tubular member, the end face being axially spaced from the seal member to define a mechanism length of the push-to-connect fitting, a ratio of mechanism length-to- minimum internal diameter of the retaining ring ranging from 0.5:1-0.6:1.

172. The sprinkler assembly of claim 155, wherein the push-to-connect fitting defines an overall axial height, the releasing member having an end face with a central opening axially aligned with the internal conduit of the tubular member, the end face being axially spaced from the seal member to define a mechanism length of the push-to-connect fitting, the ratio of mechanism length-to-overall axial height being less than 0.4:1.

173. The sprinkler assembly of any one of claims 155-172, further comprising an escutcheon having a receiver and a rim, the receiver being disposed about the releasing member to form an annular aperture between the receiver and the fire protection sprinkler, the releasing member having a peripheral surface in surface contact engagement with the receiver such that the releasing member traverses the annular aperture.

174. The sprinkler assembly of any one claims 155-172, further comprising an escutcheon having a receiver and a rim, the receiver being disposed about the releasing member to form an annular aperture between the receiver and the fire protection sprinkler, the releasing member having a peripheral surface in surface contact engagement with the receiver such that the releasing member traverses the annular aperture and contacts the receiver.

175. The sprinkler assembly of any one of claim 174, wherein the traversing portion of the releasing member circumscribing the longitudinal axis to conceal the pipe connection end. 176. The sprinkler assembly of claim 174, wherein the escutcheon has a first end and a second end, the rim formed at the second end with the releasing member located between the first and the second end.

177. The sprinkler assembly of any one of claims 155-172, further comprising:

a support cup having a central hole with a plurality of openings about the central hole, the support cup disposed over the sprinkler body such that the releasing member overlays the plurality of openings; an escutcheon engaged with the support cup, the escutcheon having a receiver and a rim; and

a cover coupled to the rim by a thermally responsive material to conceal the deflector. 178. The sprinkler assembly of any one claims 155-177, wherein the sprinkler is an automatic sprinkler having a thermally responsive seal assembly to control fluid discharge from the outlet.

179. A sprinkler assembly comprising:

a fire protection sprinkler having a body defining an inlet and an outlet with an internal passageway extending along a longitudinal axis between the inlet and the outlet, the body including an encasing surface about the internal passageway; and

a push-to-connect fitting including:

a tubular member with an end for connection to a pipe, the tubular member including an exterior surface and an inner surface, the inner surface defining an internal conduit that receives the body of the sprinkler;

a seal member and a retaining ring disposed within the internal conduit, the seal member forming a fluid tight seal about the encasing surface of the sprinkler body, the retaining ring engaged in a grip about the encasing surface of the body; and

a releasing member that translates with respect to the tubular member to disengage the grip of the retaining ring about the outer encasing surface of the body; and a resistance member to control relative translation between the releasing member and, the tubular member.

180. The sprinkler assembly of claim 179, wherein the resistance member is a resilient biasing element to bias the releasing member out of contact with the retaining ring.

181. The sprinkler assembly of claim 180, wherein the resistance member is a leaf spring.

182. The sprinkler assembly of claim 179, wherein the resistance member forms a positive lock between the tubular member and the releasing member.

183. The sprinkler assembly of any one claims 179- 182, wherein the resistance member is disposed between the tubular member and releasing member.

184. The sprinkler assembly of claim 179, wherein the tubular member includes a first end and a second end, the second end including an annular flange formed about the second end of the tubular member with a circumferential groove along the exterior surface of the annular flange.

185. The sprinkler assembly of claim 179, wherein the peripheral surface of the tubular member includes a circumferential groove and the releasing member includes an annular projection engaged within the circumferential groove.

186. The sprinkler assembly of claim 185, wherein the tubular member includes a first end and a second end, the second end including an annular flange formed about the second end of the fitting with the circumferential groove formed about the peripheral surface of the annular flange, the groove defines a groove height and an amount of axial of relative translation between the fitting and the releasing member.

187. The sprinkler assembly of any one of claims 179- 186, wherein the tubular member includes a first annular seat member and a second annular seat member axially spaced apart along the internal conduit to define a gap region therebetween; the seal member seated and the retaining ring disposed in the gap region, the seal member being seated against the first annular seat member and the retaining ring seated against the second seat member, the releasing member includes an inner wall disposed in the internal conduit and freely centered in a central opening of the second annular seat to release the sprinkler body upon axial translation of the releasing member, the releasing member including an outer wall circumferentially spaced from the inner wall having an projection engaged with the exterior surface of the tubular member.

188. The sprinkler assembly of any one of claims 179-187, further comprising a pipe fitting disposed about the tubular member, the pipe fitting is any one of an elbow fitting, a tee fitting or a union.

189. The recessed sprinkler assembly of claim 188, wherein the pipe fitting is a tee fitting having axially aligned outlets and the recessed sprinkler assembly includes two escutcheons each disposed in the one of the axially aligned outlets, each escutcheon having a push-to- connect fitting engaged within a receiver of the escutcheon inserted in one of the axially aligned outlets and centered within an annular wall of an outer escutcheon member to provide a back-to-back arrangement.

190. The sprinkler assembly of any one of claims 179- 188, wherein the releasing member includes an inner wall disposed in the internal conduit and freely centered in tubular member to release the sprinkler body upon axial translation of the releasing member, the releasing member including an outer wall circumferentially spaced from the inner wall having a projection engaged with the peripheral surface of the push-to-connect fitting, the inner and outer walls define an annular channel in between for receiving and end of the tubular member and housing the resisting member to resist the axial translation between the tubular member and the releasing member.

191. The sprinkler assembly of claim 179, wherein the tubular member includes a first end and a second end, wherein the first end of the tubular member defines a first diameter and the outer wall of the releasing member defines a second diameter, a ratio of the first diameter to the second diameter is 2:1.

192. The sprinkler assembly of claim 179, wherein the releasing member coupled to the tubular member that translates with respect to the tubular member to disengage the retaining ring grip about the outer encasing surface of the body, the releasing member having an end face with a central opening axially aligned with the internal conduit with the sprinkler body, the end face being axially spaced from the seal member to define a mechanism length of the push-to-connect fitting, the ratio of mechanism length-to- minimum internal diameter of the retaining ring ranging from 0.5:1-0.6:1.

193. The sprinkler assembly of claim 179, wherein the releasing member that translates with respect to the tubular member to disengage the retaining ring grip about the encasing surface of the body, the second end of the push-to-connect fitting having an end face with a central opening axially aligned with the internal conduit with the sprinkler body, the end face being axially spaced from the seal member to define a mechanism length of the push-to- connect fitting, the ratio of mechanism length-to-overall axial height being less than 0.4:1. 194. The sprinkler assembly of any one claims 179- 188, further comprising an escutcheon having a receiver and a rim, the receiver being disposed about the releasing member to form an annular aperture between the receiver and the fire protection sprinkler, the releasing member having a peripheral surface in surface contact engagement with the receiver such that the releasing member traverses the annular aperture.

195. The sprinkler assembly of claim 194, wherein the escutcheon has a first end and a second end, the rim formed at the second end with the releasing member located between the first and the second end, the escutcheon translating with respect to the tubular member to define an adjustable deflector-to-rim distance between the rim of the escutcheon and the deflector of the sprinkler, the escutcheon being in sliding surface contact with a portion of a peripheral surface of the releasing member.

196. The sprinkler assembly of any one of claims 179- 188, further comprising:

a support cup having a central hole with a plurality of openings about the central hole, the support cup disposed over the sprinkler body such that the releasing member overlays the plurality of openings;

an escutcheon engaged with the support cup, the escutcheon having a receiver and a rim; and

a cover coupled to the rim by a thermally responsive material to conceal the deflector.

197. A sprinkler assembly comprising:

a fire protection sprinkler having a body defining an inlet and an outlet with a passageway extending between the inlet and the outlet along a longitudinal axis, a deflector supported by the body and spaced from the outlet, the body having an outer encasing surface surrounding at least a portion of the passageway; and

a push-to-connect fitting including: a tubular member with an exterior surface and an inner surface, the inner surface defining an internal conduit that receives the body of the sprinkler;

a retaining ring disposed within the conduit engaged in a grip about the outer encasing surface of the body;

a releasing member that translates with respect to the tubular member to disengage the retaining ring grip about the outer encasing surface of the body; and

an integral annular sealing member disposed within the internal conduit to form a fluid tight seal about the encasing surface of the sprinkler body, the annular sealing member having a support base and at least two annular sealing surfaces axially spaced apart and integrated with the base to contact the outer encasing surface of the sprinkler body and form the fluid tight seal about the encasing surface,

the releasing member is secured to the exterior surface of the tubular member.

198. The sprinkler assembly of claim 197, wherein the tubular member includes a first end and a second end, the second end including an annular flange formed about the second end of the fitting with a groove formed along the exterior surface of the annular flange.

199. The sprinkler assembly of claim 198, wherein the groove is a circumferential groove and the releasing member includes an annular projection engaged within the circumferential groove, the groove defines a groove height and an amount of axial translation between the tubular member and the releasing member. 200. The sprinkler assembly of claims 197-199, wherein the push-to-connect fitting includes a first annular seat member and a second annular seat member axially spaced apart along the conduit to define a gap region therebetween; the seal member seated and the retaining ring disposed in the gap region, the seal member being seated against the first annular seat member and the retaining ring seated against the second seat member.

201. The sprinkler assembly of any one of claims 197-200, further comprising a pipe fitting disposed about the tubular member, wherein the pipe fitting is a tee fitting having axially aligned outlets with two escutcheons each disposed in the one of the axially aligned outlets, each escutcheon having a push-to-connect fitting engaged within a receiver of the escutcheon inserted in one of the axially aligned outlets and centered within an annular wall of an outer escutcheon member to provide a back-to-back arrangement.

202. The sprinkler assembly of any one of claims 197-200, wherein the releasing member includes an inner wall disposed in the internal conduit and freely centered in a central opening of the second annular seat to release the sprinkler body upon axial translation of the releasing member, the releasing member including an outer wall circumferentially spaced from the inner wall having a projection engaged with the exterior surface of the tubular member.

203. The sprinkler assembly of claim 202, wherein the inner and outer walls define an annular channel in between for receiving and end of the tubular member and housing a resisting member to resist the axial translation between the tubular member and the releasing member.

204. The sprinkler assembly of any one of claims 197-203, wherein the tubular member includes a first annular seat and a second annular seat spaced apart to define a gap region therebetween for housing the seal member and the retaining ring.

205. The sprinkler assembly of claim 204, wherein the body defines a body length ranging from 1.5-2.0 inches.

206. The sprinkler assembly of 205, wherein the passageway of the sprinkler body includes a first portion adjacent the inlet having a constant internal diameter and a second portion adjacent the outlet having a variable diameter that narrows in a direction of flow from inlet- to-outlet, the passageway defining a total passageway ranging from 1.5-2.0 inches.

207. The sprinkler assembly of claim 206, wherein the first portion has an axial length to define a body length-to-axial length ratio of 2:1-3:1.

208. The sprinkler assembly of claim 207, wherein the second portion defines a taper defined by an included angle that ranges from 7° to 8°.

209. The sprinkler assembly of claim 208, further comprising a third portion between the first and second portion defining a variable diameter that narrows in the direction of flow, the third portion defined by an included angle that ranges from 15° to 20°.

210. The sprinkler assembly of claim 209, wherein the sprinkler body defines a body diameter of 0.9-1.0 inch.

211. The sprinkler assembly 197, wherein the releasing member translates with respect to the tubular member to disengage the retaining ring grip about the encasing surface of the body, the releasing member having an end face with a central opening axially aligned with the internal conduit with the sprinkler body, the end face being axially spaced from the seal member to define a mechanism length of the push-to-connect fitting, a ratio of mechanism length-to- minimum internal diameter of the retaining ring ranging from 0.5:1-0.6:1.

212. The sprinkler assembly of claim 197, wherein the releasing member translates with respect to the tubular member to disengage the retaining ring grip about the outer encasing surface of the body, the tubular member having an end face axially spaced from the seal member to define a mechanism length of the push-to-connect fitting, a ratio of mechanism length-to-overall axial height being less than 0.4: 1.

213. The sprinkler assembly of any one of claims 197-212, further comprising an escutcheon having a receiver and a rim, the receiver being disposed about the releasing member to form an annular aperture between the receiver and the fire protection sprinkler, the releasing member having a peripheral surface in surface contact engagement with the receiver such that the releasing member traverses the annular aperture.

214. The recessed sprinkler assembly of claim 213, wherein the escutcheon has a first end and a second end, the rim formed at the second end with the releasing member located between the first and the second end, the escutcheon translating with respect to the tubular member to define an adjustable deflector-to-rim distance between the rim of the escutcheon and the deflector of the sprinkler, the escutcheon being in sliding surface contact with a portion of a peripheral surface of the releasing member.

215. The sprinkler assembly of any one of claims 197-212, further comprising:

a support cup having a central hole with a plurality of openings about the central hole, the support cup disposed over the sprinkler body such that the releasing member overlays the plurality of openings;

an escutcheon engaged with the support cup, the escutcheon having a receiver and a rim; and a cover coupled to the rim by a thermally responsive material to conceal the deflector.

216. A concealed sprinkler assembly comprising:

a fire protection sprinkler having a body defining an inlet and an outlet with a passageway extending between the inlet and the outlet, a deflector supported by the body and spaced from the outlet, the body having an encasing surface surrounding at least a portion nf the passageway;

a support cup having a central hole with a plurality of openings disposed about the central hole, the sprinkler body being disposed through the central hole such that the cup surrounds the sprinkler;

an escutcheon having a receiver, a rim, and a cover coupled to the rim by a thermally responsive material, the receiver engaged with the support cup to define a housing about the fire protection sprinkler such that the cover conceals the deflector; and

a push-to-connect fitting having:

a tubular member for connection to a pipe, the tubular member including an exterior surface and an inner surface, the inner surface defining an internal conduit with the body of the sprinkler received in the internal conduit;

a seal member and a retaining ring disposed within the internal conduit, the seal member forming a fluid tight seal about the encasing surface of the sprinkler body, the retaining ring engaged in a grip about the encasing surface of the body; and

a releasing member that translates with respect to the tubular member to disengage the grip of the retaining ring about the encasing surface of the body, the releasing member overlaying at least one of the plurality of openings of the support cup.

217. The concealed sprinkler of claim 216, wherein the fire protection sprinkler is centered within the housing to define an annular aperture about the fire protection sprinkler, the releasing member overlaying the annular aperture.

218. The concealed sprinkler of claim 217, wherein the fire protection sprinkler defines a maximum width within the housing, the releasing member defining a diameter greater than the maximum width .

219. The concealed sprinkler of claim 217, wherein the deflector defines a maximum width of the deflector within the housing, the releasing member defining a diameter greater than the maximum width of the deflector. 220. The concealed sprinkler of claim 219, wherein the deflector defines the maximum width within the housing, the releasing member defining a diameter greater than the maximum width of the deflector.

221. The concealed sprinkler assembly of any one of claims 216-220, wherein the releasing member is outside the housing. 222. The concealed sprinkler assembly of any one of claims 216-221 wherein the releasing member is coupled to the exterior surface of the tubular member, the exterior surface of the tubular member including a circumferential groove and the releasing member including an annular projection engaged within the circumferential groove.

223. The concealed sprinkler assembly of claim 222, wherein the tubular member includes a first end and a second end, the second end including an annular flange formed about the second end of the fitting with the groove along the exterior surface of the annular flange.

224. The concealed sprinkler assembly of claim 222, wherein the groove defines a groove height and an amount of axial of relative translation between the tubular member and the releasing member.

225. The concealed sprinkler assembly of claim 216, wherein the releasing member includes an inner wall disposed within the internal conduit of the tubular member and an outer wall that is radially spaced about the inner wall and tbrming a peripheral surface of the releasing member.

226. The concealed sprinkler assembly of claim 225, wherein the tubular member includes an annular flange formed about one end of the tubular member, the inner wall defines a central opening axially aligned with the internal conduit, the outer wall circumscribes the inner wall to define a channel therebetween to house the annular flange of the tubular member.

227. The concealed sprinkler assembly of claim 226, further including a resisting element disposed in the channel between the tubular member and the releasing member to resist a relative translation between the releasing member and the tubular member.

228. The concealed sprinkler assembly of claim 225, wherein the inner wall defines an internal diameter and the outer wall defines an outer diameter, a ratio of outer diameter-to- inner diameter being 2:1.

229. The concealed sprinkler assembly of claim 225, wherein the encasing surface of the sprinkler body defines a maximum diameter of the sprinkler body, an internal diameter of the releasing member being greater than the maximum diameter, the internal diameter being greater than 0.9 inches.

230. The concealed sprinkler assembly of claim 216, wherein the retaining ring includes a plurality of prongs radially disposed about a base to grip the sprinkler body, the releasing member being translatable with respect to each of the sprinkler body and the tubular member such that the releasing member contacts the retaining ring to splay the plurality of prongs and release the grip about the sprinkler body.

231. The concealed sprinkler assembly of claim 216, further including a resistance member to control relative translation between the releasing member and the tubular member.

232. The concealed sprinkler assembly of claim 231, wherein a peripheral surface of the tubular member includes a groove, the releasing member including a projection engaged within the groove.

233. The concealed sprinkler assembly of any one of claims 216-232, wherein the tubular member includes a first annular seat member and a second annular seat member axially spaced apart along the conduit to define a gap region therebetween; the seal member and the retaining ring disposed in the gap region with the seal member being seated against the first annular seat member and the retaining ring seated against the second seat member.

234. The concealed sprinkler assembly of any one of claims 216-233, further comprising a pipe fitting disposed about the tubular member.

235. The concealed sprinkler assembly of claim 234, wherein the pipe fitting is any one of an elbow fitting, a tee fitting or a union. 236. The concealed sprinkler assembly of any one of claims 216-235, wherein the cover of the escutcheon is a flat plate cover and the deflector of the fire protection sprinkler is supported from the outlet in a drop-down arrangement.

237. The concealed sprinkler assembly of any one of claims 216-235, wherein the cover of the escutcheon is a domed cover and the deflector of the fire protection sprinkler is supported from the outlet in a fixed spaced apart arrangement.

238. The concealed sprinkler assembly of any one of claims 216-237, wherein the sprinkler is an automatic sprinkler having a thermally responsive seal assembly to control fluid discharge from the outlet

239. A method of providing a concealed sprinkler, the method comprising

providing a sprinkler assembly including:

a fire protection sprinkler having a body defining an inlet and an outlet with a passageway extending between the inlet and the outlet, a deflector supported by the body and spaced from the outlet, the body having an encasing surface surrounding at least a portion of the passageway;

a support cup having a central hole with a plurality of openings disposed about the central hole, the sprinkler body being disposed through the central hole such that the cup surrounds the body of the sprinkler;

an escutcheon having a receiver, a rim, and a cover coupled to the rim by a thermally responsive material, the receiver engaged with the support cup to define a housing for the sprinkler deflector with the cover concealing the deflector; and

a push-to-connect fitting having a tubular member with an exterior surface and an inner surface, the inner surface defining an internal conduit that receives the body of the sprinkler, the push-to-connect fitting including a seal member and a retaining ring disposed within the conduit to form a fluid sealing grip about the encasing surface of the body, the push-to-connect fitting including a releasing member that translates with respect to the tubular member to disengage the retaining ring grip about the encasing surface of the body, the releasing member overlaying the plurality of openings of the support cup,

the method including distributing the sprinkler assembly for the protection of an area separated from a confined area by a barrier, the distributing including distributing the sprinkler assembly for connection to a firefighting fluid supply pipe located in the confined area with the push-to-connect fitting.

240. The method of claim 239, wherein providing the sprinkler assembly includes providing the tubular member of the push-to-connect fitting affixed within a pipe fitting.

241. The method of claim 239, wherein providing the sprinkler assembly includes providing a flat plate as the cover of the escutcheon.

242. The method of claim 239, wherein providing the fire protection sprinkler assembly includes providing a domed cover as the cover of the escutcheon.

243. A method of concealed sprinkler installation comprising

centering a sprinkler connected to a tubular member of a push-to-connect fitting within an annular receiver of an escutcheon engaged with a supporting cup having a plurality of openings centered about the sprinkler; and

overlaying the plurality of openings with a releasing member of the push-to- connect fitting.

244. A concealed sprinkler connection comprising:

a support cup having a central hole with a plurality of openings disposed about the central hole; an escutcheon having a receiver, a rim, and a cover coupled to the rim by a thermally responsive material, the receiver engaged with the support cup to define a housing for a fire protection sprinkler such that the cover conceals the sprinkler; and

a push-to-connect fitting having:

a tubular member for connection to a pipe, the tubular member including an exterior surface and an inner surface, the inner surface defining an internal conduit;

a seal member and a retaining ring disposed within the internal conduit for forming a fluid tight sealing grip about a sprinkler body; and

a releasing member that translates with respect to the tubular member to disengage the grip of the retaining ring about the sprinkler body, the releasing member overlaying at least one of the plurality of openings of the support cup when the support cup is disposed about the sprinkler received in the internal conduit of the tubular member.

245. The concealed sprinkler connection of claim 244, wherein the releasing member includes an inner wall disposed within the internal conduit of the tubular member and an outer wall that is radially spaced about the inner wall and forming a peripheral surface of the releasing member.

246. The concealed sprinkler connection of claim 245, wherein the tubular member includes an annular flange formed about one end of the tubular member, the inner wall defines a central opening axially aligned with the internal conduit, the outer wall

circumscribes the inner wall to define a channel therebetween to house the annular flange of the tubular member.

247. The concealed sprinkler connection of claim 246, further including a resisting element disposed in the channel between the tubular member and the releasing member to resist relative translation between the releasing member and the tubular member.