The invention relates to a ladder stabiliser. The ladder stabiliser is suitable for use with a ladder to provide improved safety during use of a ladder by reducing the risk of ladder failure and enabling the ladder to be used more safely. In particular, the ladder stabiliser provides improved resistance to the ladder rotating about one of its stiles and improved resistance to slipping away from the wall as the user mounts the ladder.

Ladders have been used since ancient times and the basic design of a ladder has not changed radically in that time. Ladders generally comprise three elements; stiles (legs) rungs and feet. There has been little innovation in ladder design over this time and ladders are therefore often marketed on the basis of price rather than performance or safety. However, ladders notoriously give rise to many accidents including fatalities there being tens of thousands of ladder accidents every year in the UK and, according to industry estimates over 500,000 ladder accidents each year in Europe.

Ladders are used in a wide range of applications both domestically and commercially. The ground or wall on or against which the ladder is supported may vary greatly, potentially introducing heightened risks of ladder failure. The ground may for example be uneven or inclined, slippery or loose for example due to ice, gravel, grass, moss, building site debris and the like, all of which may present a hazard unless due care is taken by the user.

The wall against which the ladder rests may also present hazards. For example, the wall may be uneven, not precisely vertical or there may be obstructions such as windows and drain pipes, gutters and the like.

The difficulties and dangers inherent in the use of ladders have been recognised and received attention for many years. Ladder "failure", that is where a ladder collapses while in use, may arise due to a number of reasons including "flip", sideways slip of the upper end of a ladder and slippage of the foot of a ladder away from the structure against which it is being used, referred to herein as "outward slip".

In use, the user may lean laterally off the ladder and thereby impart greater force to one side or the other of the ladder and cause the top of the ladder to move or to "flip". "Flip" involves one of the stiles being urged away from contact with the ground and wall such that the other stile remains the sole point of contact with the ground and the other stile rotates or pivots about the stile remaining in contact with the ground and wall. Flip is particularly dangerous as once the ladder becomes unstable together with the weight of the user exacerbating the instability, serious accidents may occur. Where a ladder is used towards the end of a wall, lateral slippage may cause the ladder to move beyond the end of the wall and lose support altogether with potentially major consequences. The base of the ladder may also slip away from the wall leading to ladder failure.

In Europe, ladders must comply with legislation regarding working at height in certain countries, for example Work At Height Regulations (WAHR) in the UK, based on a European Directive 2001/45/EC and employers may have a duty of care to employees to ensure equipment used in the course of employment is safe and meets all appropriate regulations.

As of 2010, the UK Health and Safety Executive updated an existing operational circular (Operational Circular 200/30) on the "Safe Use of Ladders and Stepladders" to a wide range of inspectors in different organisations in which it indicated that was not aware of any effective ladder stability devices on the market which complied with Contract Research Report 423/2002, known as the "Loughborough Report RR205" into ladder safety.

The Loughborough Report identified four failure modes in normal ladder usage namely, base out-slip, loss of top contact, top side-slip and flip. A video of these forms of failure and including reference to research carried out under the Loughborough Report may be found at https://www.youtube.com/watch ?v=PQ9Et9WNBak.

In the Loughborough Report, these failure modes were tested using a 60kg vertical load at the applied load point (ALP) and a horizontal load of 13kg away from the wall through the ALP for base-out slip, a vertical load of 60kg and a horizontal load of 23kg parallel to the wall and away from the ladder through the ALP for top side slip and, for assessing flip, a vertical load of 128kg and a horizontal load of 23kg parallel to the wall and away from the ladder through the ALP. The ALP was 39cm from the top of the ladder and 135mm horizontally outwards from the outer-most point at which the users foot can stand on a ladder rung. The arrangements for these tests are shown in Figure 1 described below.

In another safety test being developed in the European ladder industry for approval by the European Commission, including EN131 , a European ladder standard, to test base slip, a ladder to be tested is leant against a wall at the angle of 1 in 4 on a sheet of Float Glass and the base of the ladder is prevented from slipping by a wooden bar. A 147kg weight is suspended from the second top rung. This arrangement is left alone for 4 minutes when the wooden bar is removed. Provided the ladder moves less than 40mm in 4 minutes upon removal, it is deemed to have passed the test. This test is not a dynamic test in that it does not take account of movement of the user on a ladder nor imparting additional load or load in a different direction to the weight of the user, for example when leaning to one side when flip may occur. Many devices have been proposed for imparting improved stability to a ladder at the upper end of the ladder, for example stand-offs, and the lower end, for example attachments to the feet of the ladder or plate-like devices having upstanding parts to provide a physical abutment for the feet of the ladder to reduce the risk of outward slip, for example as described in GB-A-2216168. Also ladders having wide base bars with feet are also known but these essentially move the ladder feet to the side of the ladder and although this helps in reducing some sideways movement this has minimal benefit in reducing outward slip.

Outward slip arises due to the weight of the user and ladder presenting a force having a significant resolvable horizontal component, referred to as a slip force, which exceeds the frictional force between the ladder feet and the ground. Outward slip remains a significant problem due to a wide range of surfaces upon which a ladder might be used, the wide range of applications and also due to user error or lack of care.

A ladder is generally stable until a user climbs on ladder at which point, the motion of the user and their weight distribution places the ladder in a dynamic environment. In particular, as the user climbs and descends a ladder the user movement may cause the ladder to rise and fall slightly. This can lead to the ladder gradually creeping outwards with increasing risk of outward slip until it reaches a failure point and collapses catastrophically. The rise and fall movement of the ladder arises due to flexing of the stiles or bouncing of the stiles on the ground. Ladders are made of a wide range of materials and different qualities of construction such that the level of flex may vary widely from ladder to ladder. Safe usage however is a universal requirement for all ladders. Accordingly, in order to provide a realistic test of ladder stability, ladder testing should reflect the fact that failure occurs when the ladder bears the weight of the user and an additional load is applied, for example causing flip or when the user moves. The Loughborough tests are the closest approximation to testing a ladder in use and provide a stringent test for the known manners of ladder failure.

The up and down movement also may give rise to undesirable movement or resonance at the top of the ladder and wheels have been fitted at the top of ladders to dissipate this energy. Movement or resonance at the top of the ladder may be reduced by reducing the angle of the ladder but this increases the risk of outward slip. During manufacture and supply of ladders, ladders may be readily stacked or stored for shipment. In commercial applications, ladders are often transported on the roof of a vehicle, mounted on a roof-rack, often with space for two or more ladders to be mounted side-by- side. It is illegal in the UK for ladders to extend outside the sides of the vehicle carrying them. It is also desirable that the ladders may be snugly mounted side by side. During use, fittings which extend to a significant degree laterally of the ladder stiles cause inconvenience especially when moving a ladder in a confined space or where scaffolding is present such as during construction of houses or in work premises. Ladder extension bars which may be affixed, for example bolted across the bottom of the ladder stiles are in common use. These bars essentially provide a significantly wider base for the ladder and typically are at least 10% of the length of the extended ladder plus the width of the stiles up to 1 .2m. As the bar is close to the ground and typically are slightly raised from the ground by the thickness of a rubber foot, such bars are prone to instability on uneven ground where unevenness may cause the bar to be grounded between its ends and wobble on a fulcrum of raised ground. Ladder extender bars, being up to 1 .2m in length, are cumbersome and hinder convenient use, transport and storage. Whilst ladders may be supplied with such an attachment, workmen have been known to not use or to remove extender bars due to inconvenience during use, storage or transportation.

Provision of complex or cumbersome fittings or attachments would not be satisfactory as regards ease of storage or transport of ladders and there is little or no evidence to show that ladder extension bars provide any material improvement in ladder safety whilst being cumbersome.

Any modifications to improve safety during use would also need to avoid compromising ease of storage or transportation. Accordingly, there remains a need to improve ladder safety especially as regards flip and outward slip whilst ensuring the ladder is readily storable and transportable and may be produced economically.

We have now found that the problem of outward slip and flip may be ameliorated by providing a ladder stabiliser which holds the ladder off the ground thereby avoiding the risk of grounding and pivoting associated with ladder extender bars, links the two stiles together and has supporting feet connected to each other by a longitudinal body engageable with the ladder with the feet being located such that in use they engage the ground at a point laterally of but close to the stiles whilst the ladder and stabilizer remain movable relative to each other. The invention provides in a first aspect a ladder stabiliser for use with a ladder comprising two stiles positioned against a wall, the ladder stabiliser comprising a longitudinal body, two feet mountable on the longitudinal body at relative positions such that the spacing between the feet is greater than the spacing between the stiles of the ladder, the arrangement being such that in use the feet are located at points outboard of the ladder stiles and the ladder stiles are not in contact with the ground and, preferably, the feet are rotatable about a horizontal axis defined by the longitudinal body. The feet are suitably coaxially mounted on the longitudinal body about the axis of the longitudinal body. The feet are accordingly connected to each other via the longitudinal body. Suitably the feet are rotatably mounted on the longitudinal body such that they may rotate in a vertical plane when the stabilizer is placed on the ground for use. The feet and longitudinal body together form a single apparatus which is engagable with the ladder, for example through apertures in the ladder stiles, through a hollow rung of the ladder or by employing brackets which are adapted to be attached to ort engage with the ladder and to receive the longitudinal body. The ladder may be provided with a connecting tube between the two stiles located beneath the bottom rung with the stiles having apertures such that the longitudinal body may be passed through the apertures and the connecting tube thereby to engage rotatably with the ladder. The ladder is suitably mounted on the stabilizer so it may pivot about the longitudinal body.

In a second aspect the invention provides a method of stabilizing a ladder in use comprising providing a ladder stabiliser comprising a longitudinal body, two feet mountable on the longitudinal body at relative positions such that the spacing between the feet is greater than the spacing between the stiles of the ladder engaging the longitudinal body with the ladder directly, for example by passing through apertures in the stiles of the ladder or by passing through a hollow stile of the ladder, such that the ends of the longitudinal body extend outboard of the ladder stiles and securing the feet on each end of the longitudinal body at a position outboard of the stiles whereby the ladder is supported of the ground by the stabilizer and, preferably pivotally mounted about the longitudinal body.

If desired, one of the feet may be secured to the longitudinal body before it is engaged with the ladder, the remaining foot then being secured to the longitudinal body to secure the stabilizer to the ladder. Optionally, the stabilizer may be engaged with the ladder using brackets which are adapted to be secured to the stiles of the ladder and to receive the longitudinal body. The brackets, preferably two, are suitably rotatably mountable on the longitudinal body and adapted for engagement with a ladder stile.

Advantageously, we have found that a stabilizer according to the invention enhances the resistance to outward slip and to flip as compared to the same ladder without use of the stabilizer. The longitudinal body effectively ties the stiles together maintaining the stiles and the longitudinal body in a planar arrangement whilst allowing rotational movement of the stiles about the longitudinal body. During flip, one stile necessarily will need to be urged away from the wall whereby the two stiles are not equidistant to the wall. Linking the stiles using the longitudinal body through the agency of the brackets, provides resistance to this tendency to flip, thereby improving ladder stability. The present invention also surprisingly improves resistance to outward slip. As the user moves on a ladder, transferal of weight may cause the ladder to judder or flex and this may give rise to small movements at the foot of the ladder stiles which cumulatively may lead to outward slip. As the present invention provides a stabilizer which is rotatably movable relative to the ladder, the force transmitted by movement of the user is dissipated into the stabilizer and acts in a generally vertical direction and over a wider "footprint" than a ladder without a stabilizer. By having a wider base and relative movement between the longitudinal body and the ladder, the urge for the stiles to slip away from the wall is reduced.

The longitudinal body suitably comprises securing means for example a screw thread to allow the feet to be secured in a certain position along the longitudinal body for example by using a nut engagable with the screw thread. The feet are preferably secured in place using securing means, preferably a screw thread on the longitudinal body and a securing nut. If desired the aperture in the feet comprises a complementary screw thread such that the feet may be screwed onto the longitudinal body and adjusted to the desired location. The feet are preferably secured close to and especially abutting the outer side of the ladder stiles.

The longitudinal body is suitably an axle. The feet of the stabilizer are mounted on the axle such that the feet may freely rotate about the axle. Preferably, the feet are removably securable on the axle so that one foot may be removed to allow the user to thread the axle through apertures in the brackets which are each connectable to a ladder stile or to pass through apertures in the ladder stiles. The axle thereby connects the two stiles and restricts movement of the ladder stiles in any direction other than rotationally about the axle or in a sliding manner along the axle.

The feet are mounted on the longitudinal body. One or both feet may be removably secured to the longitudinal body. When mounted on the longitudinal body, the feet may be fixed relative to it for example they may be clamped or mounted with a screw thread or locking nut, or the feet may be rotatable about the longitudinal body. If the feet are rotatable, they should nevertheless not be movable along the longitudinal body to provide a suitably stable base. The feet suitably comprise an aperture for the longitudinal body to pass through and are rotatable about the longitudinal body. The aperture suitably may receive a bush or insert, for example tubular steel or PTFE to receive the longitudinal body and which provides strength or reduces friction allowing substantially free rotation of the ladder relative to the longitudinal body.

In a preferred embodiment, the feet have a framework structure comprising flat surfaces for engagement with the ground, a ring defining an aperture and arms extending from the flat surfaces to the aperture. The feet may be solid bodies and made of any suitable material preferably plastics, for example injection moulded plastics or metal for example aluminium. The feet present a flat surface to the ground and the surface of the foot may comprise a contoured surface and be made of any suitable material, for example plastics or rubber material. A metal, for example, aluminium, may be extruded to provide a foot a triangular or box cross-section with arms extending from each side of the triangular or box section to a ring which defines the aperture. Feet having a similar design may be made of plastics material and produced by injection moulding. Provision of an insert for the aperture improves the strength and durability of extruded aluminium feet. The flat surfaces of the aluminium or plastics feet may have a plastics or rubber pad to provide enhanced friction with the ground.

Alternatively to the feet presenting a flat surface, the feet may comprise one or more legs or a cup which engages with the ground.

In one embodiment, the feet are of polygonal shape, for example square or triangular and are configured to present an edge to the ground in use. The aperture passes through the foot to allow the longitudinal body to be aligned horizontally in use and parallel to the surface of the foot which engages the ground. Each foot suitably has two or more surfaces for engagement with the ground at the selection of the user with each surface being a different distance from the aperture for the longitudinal body. Thus the aperture may be located centrally in the foot or is preferably offset providing different distances from the aperture to each side so the foot may be rotated to a desired position enabling the stabilizer to be employed on uneven or sloping ground and to present a horizontal longitudinal body such that the ladder when mounted on the stabilizer is substantially vertical. The feet are suitably mounted on the longitudinal body such that, in use, the feet are outwardly located of the ladder stiles but are close to the outer side of the ladder stiles. Preferably, the longitudinal body with the feet affixed extends beyond the ladder stiles and the total length of the stabilizer is less than the sum of 10% of the extended height of the ladder plus the width of the stiles. In a preferred embodiment, the feet or fixings to secure the feet on the longitudinal body, suitably abut the outer face of the stile.

Advantageously, the stabilizer does not extend too far laterally of the ladder and provides improved ladder stability without introducing inconvenience to the user when transporting or storing the ladder as is experienced when a ladder extended bar has been bolted across the base of the ladder.

In one embodiment, the stabilizer is suitably connected to the ladder by means of two brackets which are rotatably mountable on the longitudinal body and adapted for engagement with a ladder stile, as shown in Figure 3.

Where used, each bracket is releasably securable to a ladder stile such that the bracket remains in secure, fixed relation to the ladder stile in use. Preferably the bracket comprises a mating part adapted to engage releasably with the ladder stile. Aluminium and steel ladders may have hollow stiles with a plug closing the aperture and suitably the bracket is adapted to engage with the aperture at the end of the ladder stile to provide a fixed relationship between the ladder and the brackets. By engaging with aperture in the ends of the hollow stiles no modifications to the ladder are required. This enables ladder manufacturers to continue producing ladders of known designs whilst the stabiliser provides improvements in stability without requiring the integrity of the ladder to be compromised. Each bracket suitably comprises an aperture for receiving the longitudinal; body such that the bracket is rotatable about the longitudinal body. The brackets may be removed from the longitudinal body by removing a foot and sliding the brackets off. In one embodiment, the brackets are not removable from the longitudinal body and the feet are not removable from the longitudinal body.

The apertures in the feet and the longitudinal body are suitably dimensioned so as to provide a snug fit between the feet and the longitudinal body whilst preferably ensuring the feet are rotatable on the longitudinal axis. The longitudinal body is suitably dimensioned to allow a snug and preferably rotatable fit with apertures in the ladder stiles or hollow rung. Where brackets are employed, the longitudinal body and the apertures in the brackets are suitably dimensioned so as to provide a snug, preferably rotatable fit. In a third aspect, the invention provides a ladder stabiliser for use with a ladder comprising two stiles positioned against a wall wherein the ladder stabiliser comprising a longitudinal body, two feet mountable on the longitudinal body at relative positions such that the spacing between the feet is greater than the spacing between the stiles of the ladder and wherein the longitudinal body is adapted for releasably securable attachment to the ladder such that the ladder stiles are rotatable relative to the longitudinal body, the arrangement being such that in use the feet are located at points outboard of the ladder stiles and the ladder stiles are not in contact with the ground.

The stabiliser in the third aspect of the invention is especially suitable for use with a ladder having hollow rungs or with apertures formed in the ladder stiles such that the stabiliser may be engaged with the ladder by threading the longitudinal body through the internal surface of the rungs or through the apertures. This arrangement also beneficially reduces intrusion and a potential obstacle for the user. Also, if the physical construction of a ladder is altered including drilling holes in it to fit an accessory, standards associated with British and European legislation or standards guidelines may be compromised. By engaging with hollow rungs, the stabiliser does not require the integrity of the ladder to be compromised.

We have also surprisingly found that to a user, a ladder mounted with a stabilizer of the invention has a robust feel and is much more difficult to move away from a wall than a comparable ladder standing on the ground. This enhanced "feel" is beneficial to the user and provides a basis for confidence in the safe usage of the ladder. Suspending the ladder above the ground with the stabiliser feet outboard of the stiles provides a "damper" effect such that changes in force due to movement of the user may be absorbed to a degree thereby reducing the slight up and down motion of the ladder and reducing the risk of outward slip. As compared to employing a ladder in a conventional way, the stabiliser enables a greater normal force to pass from the stabiliser to the ground and a lower slip force, thereby reducing the dependency on friction to keep the ladder in position. The invention is particularly suitable for use where higher risks of outward slip may arise due to the reduced reliance on friction between the ladder and surface to avoid outward slip. Advantageously, the stabiliser is constructed and configured such that it may be used with any design of ladder. This allows ladders of different materials of construction, lengths and qualities to be stabilised by use of the stabiliser, whether ladders for professional use or private or domestic use, and whether indoors or outside. The stabiliser does not require any additional means of securing the ladder to the stabiliser and provides a readily usable and removable device thereby allowing ladders to be stored and transported in established ways and using existing vehicles.

In a further aspect, the invention provides a kit of parts for assembly into a ladder stabilizer comprising:

i) a longitudinal body;

ii) two feet mountable on the longitudinal body at relative positions such that the spacing between the feet is greater than the spacing between the stiles of the ladder and the feet; and

iii) optionally two brackets adapted to be rotatably mountable on the longitudinal body and adapted for engagement with a ladder stile.

In another aspect, the invention provides a kit of parts for assembly into a stabilised ladder comprising:

i) a stabiliser according to the invention adapted to be engaged with a ladder; and

ii) a ladder, adapted to be engaged with the said stabiliser.

The invention is illustrated in a non-limiting manner by reference to the accompanying drawings in which:

Figure 1 shows a ladder against a wall with an ALP arrangement according to the Loughborough test referred to herein; Figure 2 shows a perspective view of a ladder stabiliser according to the invention; Figure 3 shows a perspective view of another ladder stabiliser according to the invention engaged to the ladder using brackets;

Figure 4 shows a perspective view of a foot of a ladder stabiliser according to the invention;

Figures 5A shows a side view of a ladder and ladder stabiliser arrangement according to the invention used to test for flip and top sideways slip;

Figure 5B shows a front elevation of a ladder and ladder stabiliser arrangement according to the invention used to test for loss of top contact and bottom slip;

Figures 6 shows a front elevation of an arrangement used to test for loss of top contact and bottom slip of a naked ladder, not according to the invention;

Figures 7A to 7C show a front elevation of an arrangement used to test for base slip;

Figures 7D to 7F show side elevation of the arrangements shown in Figures 7A to 7C respectively;

Figure 8 shows a front elevation of a ladder mounted on a stabiliser according to the invention on sloping ground; and

Figure 9 shows a perspective view of a ladder kit according to the invention.

Figure 1 shows a ladder (1 ) standing on the ground (2) and leaning against a wall (3). An applied load point (ALP) (4) is mounted on the ladder (1 ). Vertical loads may be applied by hanging the load from point B on the ALP in direction X. Loads may be applied horizontally and parallel to the wall in direction Y via pulley (5) or horizontally and away from the wall in direction Z via pulley (6) which may be mounted from the ceiling or in some other manner to provide a load-bearing point. Direction Z may be, for example, perpendicular to wall (3) or at 45° to the wall. The amount and direction of load applied to the ladder will vary according to the test being performed.

Figure 2 shows a stabiliser according to the invention having a longitudinal body (10) threaded through apertures (1 1 , 13) in stiles (20, 22) of ladder (24). The longitudinal body (10) is rotatable within the apertures (1 1 , 13). The longitudinal body (10) is also mounted on triangular feet (26, 28). Each foot (26, 28) has an aperture (30, 32) which is preferably offset from the centre of the triangular solid foot (26, 28) and in which the longitudinal body (10) is rotatably mountable. At least one of the feet (26, 28) is desirably removable to allow the stabiliser to be readily and easily removed from or attached to the ladder (24).

Where the ladder (24) has hollow rungs, the stabiliser according to the invention may be passed through a hollow rung of the ladder provided that the feet (26, 28) are dimensioned such that the bottom of the stiles (20, 22) remain clear of the ground. In this case and other cases where the stabiliser is attached to the ladder by other means, the ladder need not be manufactured with or modified to provide apertures (1 1 , 13). Figure 3 shows a stabiliser according to the invention having a longitudinal body (10) threaded through brackets (12, 14) having apertures (16, 18) and which are engaged with the bottom end of stiles (20, 22) of ladder (24). The longitudinal body (10) is rotatable within the apertures (16, 18). The longitudinal body (10) is also mounted on triangular feet (26, 28). Each foot (26, 28) has an aperture (30, 32) which is preferably offset from the centre of the triangular solid foot (26, 28) and in which the longitudinal body (10) is rotatably mountable. At least one of the feet (26, 28) is desirably removable to allow the stabiliser to be readily and easily removed from or attached to the ladder (24).

Figure 4 shows a foot (26, 28) produced from extruded metal, for example aluminium, having a triangular cross section which define three flat surfaces (40, 42, 44), any of which may be engaged with the ground, a ring (46) defining an aperture (30, 32) with arms (48, 50, 52) extending from the surfaces to the ring (46). Suitably, at least one of the arms (48, 50, 52) is of different length to the other arms such that the ring (46) is offset from the centre of the triangular foot. The longitudinal body is insertable in the aperture (30, 32) and the foot is rotatable about the longitudinal body so the height of the ring (46) above the ground may be readily varied to take account of a slope or unevenness. Any one or more of the surfaces (40, 42, 44) may be covered in whole or part with a rubber or plastics plate to protect the foot and/or to provide improved grip with the ground. The arrangement in Figures 5A is employed in testing for flip and sideways top slip in a manner prescribed by the Loughborough Test. Figure 5A shows a ladder mounted on a stabiliser according to the invention. The feet (26, 28) of the stabiliser are close to or abut the stiles of the ladder. The longitudinal axis (10) passes through apertures (1 1 , 13) in the stiles of the ladder. In an alternative arrangement, the ladder may be fitted with brackets (12, 14) as shown in Figure 3 and the longitudinal axis (10) passed through the apertures in the brackets. The stabiliser is mounted on a melamine board (58). The arrangement has a ladder with an ALP point (60) and a pulley (62) mounted in the same plane as the ladder so that a horizontal load parallel to the wall may be applied to the ladder. The arrangement in Figures 5B is employed in testing for loss of top contact and bottom slip in a manner prescribed by the Loughborough Test. Figure 5B shows a ladder mounted on a stabiliser according to the invention. The feet (26, 28) of the stabiliser are close to or abut the stiles of the ladder. The longitudinal axis (10) passes through apertures (1 1 , 13) in the stiles of the ladder. In an alternative arrangement, the ladder may be fitted with brackets (12, 14) as shown in Figure 3 and the longitudinal axis (10) passed through the apertures in the brackets. The arrangement has a ladder with an ALP point (60) and a pulley (64) mounted in a direction perpendicular from the wall and passing through the ALP (60) so that a horizontal load perpendicular to the wall may be applied to the ladder.

Figure 6 shows a comparative arrangement, similar to that shown in Figure 5B but with a ladder mounted directly on the melamine board 58 rather than on a stabiliser according to the invention. A stand-alone ladder without a stabiliser is typically known as a "naked" ladder.

The arrangement in Figures 5B and 5 has a ladder with an ALP point (60) for attachment of a vertical load and a pulley (64) mounted in a positon which is perpendicular to the wall so that a horizontal load perpendicular to the wall may be applied to the ladder via the ALP.

The arrangement in Figures 7A to 7F is employed in testing for base slip. In Figures 7A and 7D, the ladder has a conventional extended stabiliser bar, according to EN131 and not according to the invention and is mounted on a PTFE sheet (70). In Figures 7B and 7E, not according to the invention, the naked ladder is mounted directly on the PTFE sheet. In Figures 7C and 7F, the ladder was mounted on a stabiliser according to the invention. The bottom of the ladder was moved away from the wall progressively to the point of failure through base slip and is set out in the Examples below. Figure 8 shows a ladder (24) mounted on a stabiliser according to the invention having a longitudinal body (10) on which the triangular feet (26, 28) are mounted, the longitudinal body and triangular feet being rotatable. The longitudinal body has a screw thread for receiving securing nuts (27, 29) to hold the feet (26, 28) in position and preferably abutted against the ladder stiles (20, 22). The feet (26, 28) are secured on the longitudinal body (10) by nuts (27, 29) threaded on to the end of the longitudinal body (10), leaving a small portions (10' 10") of the body (10) protruding. The stabiliser is located on sloping and/or uneven ground (90). Each foot (26, 28) has an aperture (30, 32) which is offset from the centre of the triangular solid foot (26, 28) such that the distance from the aperture to each of the three sides is different. Each foot may be rotated so as to provide a greater or lesser vertical distance from the aperture to the surface, as shown in Figure 4 (48, 50, 52) abutting the ground and thereby allow the user flexibility to select the orientation of the feet such that the longitudinal body is substantially horizontal even on sloping ground. Figure 9 shows the kit of parts of the invention including longitudinal body (10) and triangular feet (26, 28) with optional brackets (12, 14) having apertures (16, 18) and lugs (17, 19) for insertion in hollow ends of stiles of the ladder. . Each foot (26, 28) has an aperture (30, 32) which is offset from the centre of the triangular foot (26, 28) and in which the longitudinal body (10) is rotatably mountable. The longitudinal body (10) is mountable on the feet (26, 28) and the brackets (12, 14) are adapted to be inserted into the end of hollow stiles in a ladder. At least one of the feet (26, 28) is desirably removable to allow the stabiliser to be readily and easily removed from or attached to the ladder (24).

Examples

Stability Test Method.

A ladder stabiliser according to the invention as shown in Figure 2 and Figure 3 was tested to determine ladder stability. Comparative tests with a naked ladder and a ladder with an extender bar stabiliser were also carried out.

Examples 1 to 4

An arrangement as shown in Figures 5A and 5B and Figure 6 was used in these tests.

A ladder was extended to a length of 3.3m. The ladder was arranged against a wall at an angle of approximately 75 degrees to a vertical height of 3.2m and with the base of the ladder being 850mmm from the base of the wall. The feet were positioned on a clean, dry melamine board. The top of the ladder was placed against a smooth, clean, polished stainless steel sheet surface. The ALP (Applied Load Point) fixture was affixed to the upper stile section 390mm from the top of the ladder contact point with the designated load point being horizontally away from the outside face of the stile in the same axis as the rungs at a distance of 135mm. The vertical weight was suspended from this point. This position was used for all applied loadings for stability testing of the ladder and the stabiliser mounted to the ladder.

A set load was attached at the point where the 'ALP' is attached to the supporting stile for the period of testing with the load specified applied vertically. The loads were applied via fixed masses (weights) in conjunction with load cells via the ALP in the plane stated in the specific tests. The test load was gradually applied through the ALP until failure of the contact points at the top or bottom of the ladder were detected, at this point the mass applied was recorded and the test concluded. Examples 1 and 2 (Figure 5A) - Top Sideways Slip and Flip Test

The ladder described in Example 1 and a stabiliser according to the invention as shown in Figure 2 and Figure 3 was employed in this test. A vertical load was applied at the 'ALP' mounting point on the outside face of the stile for the period of this test in the direction X in Figure 5A\ An increasing horizontal load parallel to the supporting wall was then applied through the 'ALP' and the pulley in direction Y of Figure 5A until movement is detected and the results recorded. In Example 1 , a vertical load of 100kg was applied and a horizontal load was applied. In Example 2, a vertical load of 60kg was applied and a horizontal load was applied. In Example 1 , the ladder failed at a horizontal applied load of 7kg. In Example 2, the ladder failed at an applied load of 10kg. Examples 3 (Figures 5B) - Loss of Top Contact and Bottom Slip

A vertical load was applied at the 'ALP' mounting point on the outside face of the stile for the period of this test in the direction X in Figure 5B. An increasing horizontal load perpendicular to the supporting wall was then applied through the 'ALP' and the pulley in the direction Z in Figure 5A until movement is detected and the results recorded.

In Example 3, the ladder described in Example 1 and a stabiliser according to the invention as shown in Figure 2 and Figure 3 was employed and a vertical load of 60kg was applied and a horizontal load was applied in increments to in excess of 25kg. The ladder remained stable, showing no signs of loss of top contact or bottom slip.

Example 4 (Figure 6) - Comparative

In Comparative Example 4, in which the same ladder was employed as in the previous examples and in the same arrangement but without any stabiliser, application of a vertical load of 20kg caused the ladder to fail. It was therefore not possible to increase the vertical load and to apply the horizontal load either parallel to the wall or perpendicular to the wall to test for flip, sideways slip or loss of top contact.

Comparative Examples 6 and 7 and Example 8 (Figures 7A to 7F) - Bottom slip

In these tests, an arrangement as shown in Figures 7A to 7F was employed. The ladder used in Example 1 was employed and mounted on a known extended stabiliser bar (Comparative Example 6 and Figures 7A and 7D), as a naked ladder (Comparative Example 7 and Figures 7B and 7E) and on a stabiliser according to the invention as shown in Figure 2 and Figure 3 in Example 8 (Figures 7C and 7F). The ladder stiles contacted the ground through a rigid PTFE sheet.

In each test, the ladder starting at 75 degrees and 800mm from the wall and the base of the ladder was moved outwards, thereby decreasing the angle of the ladder. The base of the ladder was moved a discrete distance until the ladder failed through base slip.

In Comparative Example 6, the base of the ladder was moved away from the wall to a distance of 900mm at which point the ladder failed. In Comparative Example 7 however, the naked ladder would not stand at 800mmm and failed on increasing the angle such that the ladder was only 750mm from the wall. In Example 8, the base of the ladder was moved to 1600mm away from the wall before failure occurred.

The results demonstrate the significantly enhanced stability as regards base slip when employing a stabiliser according to the invention as compared to a naked ladder and a ladder with an extender bar.