The term rooms refer to both particular rooms and entire or parts of prem- ises. The cleaning may include wall, floor and ceiling surfaces as well as sur- faces on furniture and other objects in the room.

STATE OF THE ART Cleaning of premises usually takes place in accordance with deter- mined intervals, or with a certain frequency, and with different permanent cleaning routines at different points of time. This implies that it is common that cleaning takes place both to often and to seldom in relation to how fouled the premises really are. The visible cleanness of the room is consid- ered, but not the technical cleanness of the room. The cleaning routine used at a specific occasion may also be unnecessarily extensive or have the wrong direction in relation to real circumstances and the current actual re- quirements.

Both cleaning to often and unnecessarily extensive cleaning cause problems with unnecessarily high use and consumption of chemicals and water. It also requires an unnecessarily high work effort by cleaning person- nel. One effect from this is that cleaning costs become higher than neces- sary. However, the higher costs do not for certain cause the cleaning to reach desired cleanness or comfort in the room, since a usually suitable cleaning routine may be insufficient in particularly fouled premises.

What may in part affect a cleaning routine is the estimation of prem- ises fouling degree made by the cleaning personnel itself. Such an estima- tion is based on the visible fouling, the so-called esthetical cleanness, i. e. presence of visible dirt or visible dirt particles. However, the visible fouling is only part of the total fouling of the room, and is often misleading and not of

great importance for estimation of the rooms cleaning requirements. For per- sons staying in or using the room, fouling in form of smaller particles, in many cases invisible for the eye, may be more important for the experience of the rooms cleanness and for the influence on a person in the room.

The condition of the premises, or a room, with reference to its clean- ness is referred to below as the comfort value of the room. Hence, the com- fort value refers in the following firstly to how clean the room is from different aspects. One aspect that particularly may be considered is the use of the room. In e. g. so-called clean rooms in industrial or medical environment, the particle content and the size of the particles are of vital importance. There is also a medical connection between the content of particles of a particular size and the presence of bacteria and the like. However, the humidity of the air and temperature or sound level in the room are factors not included in the used definition of the term comfort value.

SUMMARY OF THE INVENTION One object of the invention is to reduce or eliminate the above- mentioned problems and to provide a suitable cleaning of a room, well adapted to its purpose. According to the invention, this is accomplished in that the current comfort value of the room is continuously determined and stored and that a particular cleaning routine is determined dependent on how the comfort value fluctuated during a certain period of time. A desired and predetermined comfort value then constitutes a reference, to which the cur- rent comfort value is set. The predetermined comfort value is determined with regard to inter alia the use of the room and the degree of utilization thereof.

The comfort value of the room is determined with measuring means registering different quantities in the room. In a preferred embodiment the measuring means comprise a transducer registering the content of particles of a particular size in the room. Measurement of the content of particles has

by practise proved to be a good basis for determining cleaning programs and to a certain extent the frequency of which cleaning should take place.

Measurement signals from the transducer are continuously received at suitable intervals. Hence, alterations in the particle content in connection with activity in the room are registered. This is important since the particle content in the air alters considerably due to such activity, e. g. when people move in the room and in connection with cleaning, and peak values and subsequent lower and more stable values occurring in connection therewith should defi- nitely affect the subsequent cleaning.

A transducer in each room is connected to a control system. In the control system an automatic analysis of received measurement test results from the transducers takes place and the current comfort value of the room is determined. Before each cleaning of a room a contact is established be- tween cleaning personnel and the control system. Dependent on this analy- sis and other data associated with the room, the control system determines current cleaning information for the desired comfort value to be achieved or maintained. The desired comfort value is predetermined with regard to inter alia the use of the room and the degree of utilization.

In the control system also information about each particular room is stored, e. g. in the fashion of particular instruction packages indicating how the room is to be treated to reach the desired comfort value in relation with the current status of the room. An instruction package may also contain in- formation about which cleaning material and which cleaning method that ought to be used.

The invention presents further advantages and features, which will be evident from the following description, drawings and dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail with the aid of ex- emplary embodiments and with reference to the accompanying drawings, in which

Fig. 1 is a diagram illustrating the particle content in a room during two days, Fig. 2 is a diagram illustrating the change of the comfort value over time, Fig. 3 is a schematic perspective view of a device designed in accor- dance with the invention and Fig. 4 is a general illustration of premises with an installation according to Fig. 3 in several rooms.

DESCRIPTION The diagram in Fig. 1 indicates how the number of particles in a room varies over time. A transducer arranged in a space measures the number of particles. On the X-axis the time is indicated, four points of time T,-T4 particu- larly being marked out. On the Y-axis the number of small particles (<0.5 m) per cubic foot minute in tens of thousands is indicated. T, indicates the point of time when a working day is finished. After this point of time the transducer registers a falling number of particles, especially because less or no people are moving in the space stirring up particles.

The number of particles registered by the transducer is falling until the point of time T2, when a new working day starts. During the whole working day the number of particles is increasing, which may be registered by the transducer, since the activity in the space is high. At the point of time T3 the working day is finished at the same time as the cleaning of the space starts.

In association with the cleaning the number of registered particles increase further, but directly after the cleaning has ceased the number is falling again.

If suitable cleaning method and suitable cleaning instruments are used, the

number of particles after the cleaning will fall to a value below the lowest value present before the cleaning.

Fig. 1 shows the result of a suitable cleaning measure after the point of time T3 with an unbroken line while a dash and dot line after T3 indicates the result after a less appropriate cleaning measure, e. g. including vacuum cleaning. As appears from the dash and dot line the number of particles of the actual size will not be reduced totally in connection with the cleaning.

When the next working day begins at the point of time T4 the number of par- ticles will be larger than at the end of nearest preceding working day. The curve in Fig. 1 also shows that cleaning of the room do not take place every day. This indicates that also the cleaning measure and the cleaning fre- quency affect the cleaning result to a great extent.

Fig. 2 shows the alteration over time of the comfort value in a space.

The comfort value C is indicated on the X-axis and the time is indicated on the Y-axis. The comfort value is to a great extent dependent on the number of particles of a particular size measured by a transducer. As mentioned above, small particles are particularly important in this context, and particles smaller than 0.5 m are preferably measured. Also other particle sizes and other factors may be included in determining the comfort value. CD is the de- sired comfort value of the space. A first level L, indicates the level at which a first cleaning method M, is to be used to re-attain CD. If the comfort value is reduced to a second level L2, or below that, a second cleaning method M2 should be used. A comfort value below or equal to a third level L3 indicates that a third method M3 should be used to attain the desired comfort value CD.

The cleaning methods may also be designated instruction packages.

At the point of time T, the current comfort value is below the level L3, which implies that the method M3 is to be used. After cleaning according to the method M3 at this point of time, the comfort value increases to above the level CD. Then, when using the space the comfort value will decrease. At the point of time T2 the measured level is between the level L, and the level L2, which result in that the method M, may be used. Thereby the level is increas- ing above the level CD again. Between the points of time T2 and T3 the level

is decreasing to a low value between L2 and L3. This low value is in the range corresponding to the cleaning method M2. After this measure the level again is increasing above the level CD.

In Fig. 3 a room 10 having walls 11 and a ceiling 12 is schematically shown. The room constitutes a space which is to be supervised and cleaned according to the invention. Four transducers are arranged in the room. A first transducer 13 is arranged on a wall 11 close to the ceiling 12 of the room.

The position may vary depending on room type and the transducer design.

For most applications a position having a considerable distance to the floor is preferable. The first transducer 13 is wirelessly connected to a collecting computer 14 for continuously transmitting measurement test data regarding presence and frequency of particles in the room. The collecting computer 14 is also wirelessly connected to a manual terminal 15 having a display 16 and input means 17, the input means 17 preferably being in the form of a key set.

The display 16 may also comprise a so called touch screen, which may be actuated by the means of a narrow or pointed object, e. g. a pointer. If there are several users of the system, several manual terminals 15 are included.

A second transducer 18, which is connected to the collecting computer 14 via an electric wire 19, and a third transducer 20 may also be arranged in the room. The third transducer 20 is arranged closer to the floor of the room and is used for measuring particles closer to the floor level. Anyone of the transducers 13,18 and 20 may be designed for measuring another quantity than the other transducers. In such case, some of the transducers are pref- erably designed for measuring the humidity or the presence of substances indicating a risk of lower comfort value. Measurement values from different transducers may also be combined and give additional information about cleaning requirements. The presence of bacteria and the like may also be included in the measurement objects. The selection of a transducer is per- formed depending on the use of the room and established comfort value re- quirements.

The particle content may be measured in different ways in the trans- ducers. For instance, transducers based on laser, by the means of which

counting of particles take place, can be used. Other measurement methods are electrostatic particle counting, e. g. of the type"triboelectric", and optic measurement of luminous transmittance.

In the collecting computer 14 preferably one or more interface units 21 are included for the required communication with the transducers and the manual terminal. Further, memory means 22 and a control unit 23 for deter- mining the cleaning method are included in the collecting computer 14. Data from the transducers 13,18 and 20 and information about the rooms or spaces included in the premises, for instance regarding the desired comfort value of the rooms, is stored in the memory means 22. The control unit 23 is designed to enable configuration of transducers and manual terminals. In a smaller set-up the collecting computer 14 constitutes a central server (see Fig. 4), while a separate unit may be included in a more extensive set-up. In the central server a complex database having information about premises, spaces, cleaning personnel, cleaning routines etc. is stored. The collecting computer 14 may also be connected to a computer supplier via modem or another data connection.

The manual terminal 15 is designed with reading means 24 for input of room identification data in connection with a room ready to be cleaned. In the embodiment shown, said room identification data is available in the form of a bar code strip 25 arranged in the room. It is also possible to arrange some kind of transponders or similar devices, which in other ways transmit said room identification data to the manual terminal 15, in the rooms. In such case the manual terminal 15 is designed with means for activation of and communication with the transponder.

The collecting computer 14, having its control program, is designed to continuously collect and store measurement data from the different trans- ducers. Thereby, the comfort values in the different rooms may continuously be recorded. Different peak and bottom values as well as trends may thereby be annotated and studied to provide optimisation, accomodation or im- provement of the cleaning methods and cleaning materials.

The communication between the manual terminal and the collecting computer may take place in different manners. Preferably, a wireless trans- mission is used, e. g. with SPECTRUM 24 via access stations 26 (Access Points) according to the standard IEEE. 802.11. Access stations are arranged in the premises in question with suitable relative distance. Depending on cur- rent circumstances the access stations should be positioned with a distance of 50-300 m from each other. The access stations may be connected to the collecting computer through a main cable 27 or a similar connection. The same kind of wireless communication may also be used between the collect- ing computer and the transducers.

Fig. 4 is a synoptic view of premises having a system for cleaning op- timisation according to the invention. The premises include several rooms 10, in which transducers 13,18 and 20 are arranged in the fashion described above. All the transducers are operatively connected to the collecting com- puter 14, either through cable or through a wireless connection. Each room 10 included in the system is also equipped with a bar code strip 25. Suitably the strip 25 is positioned at an entrance of the room.

The manual terminal 15 is operatively connected to the collecting computer 14 directly or through one or more access stations 26. A database having collected data regarding premises, rooms, cleaning routines, cleaning tools, incidental materials, personnel etc. is stored in the collecting computer 14. The database is updated continuously through communication with the manual terminal. The collecting computer may also be provided with conven- tional input and output means, e. g. keyboard and screen, for updating and for transmitting statistics, orders and other information to the administration and customers.

In larger applications a central computer 28 may perform several of the functions of the collecting computer 14. Suitably the database having information about the premises and other conditions is stored both in the col- lecting computer and in the central computer.

When using the above-disclosed device, comfort values for different spaces as well as suitable cleaning methods, cleaning tools and cleaning

materials are determined. Current information about cleaning personnel and operating ranges for the personnel is stored in the same fashion. Below fol- lows a description of the use of the system with reference to Fig. 3.

Cleaning personnel arriving to the premises identify themselves to- wards the manual terminal. After exchange of information between the man- ual terminal and the collecting computer, if required, the display 16 on the manual terminal, graphically and/or through text information, shows basic information to the person who identified himself or herself and logged into the system. Further, information about which premises or rooms within the premises in which the person is to take cleaning measures is displayed. The person enters a room 10 included in a specification of the current objects and attend to that the manual terminal is updated regarding which room is in question. In a preferred embodiment this takes place by positioning the manual terminal, having its reading means 24, adjacent to or passing it by the bar code strip 25 present in the room.

Thereby, information regarding current cleaning measures and clean- ing material is displayed on the display of the manual terminal. The informa- tion presented on the display is dependent on the current comfort value of the room, the comfort value being continuously updated through transmitting measurement data from the transducers 13,18 or 20 to the collecting com- puter. Suitably the current comfort value is combined with information about previous cleaning measures and the point of time for previous cleaning in the room, so as to indicate efficient cleaning measures. The person performs the indicated cleaning measures and then confirms that the measures have been taken. Suitably this takes place in the same or corresponding fashion as before the cleaning, that is by passing the manual terminal by the bar code strip. After the confirmation the room is deleted from the specification of objects to be performed.

If the person estimates that further measures are required in the room, this is stated on the manual terminal. Suitably this takes place by starting a particular program routine in the manual terminal. The program routine en- ables input of information about which measure or measures that has been

taken and current time consumption. Information about the objects is also transmitted to the collecting computer, either directly in connection with up- dating the manual terminal or later.

When all measures taken in a room have been taken, the person again selects the routine in the manual terminal indicating which rooms are included in the assignment. The room is located and the current cleaning measures in the room are indicated on the display in the fashion described above. The procedure is repeated until all of the rooms and spaces in the premises, which are part of the persons assignment, have been treated.

The manual terminal also includes program routines for other meas- ures and exchange of information. By starting a first information routine in the manual terminal the status of the premises, i. e. information regarding a particular space about the latest cleaning, suitably both the point of time and responsible person, current comfort value C, collected earlier or is now col- lected from the collecting computer, and desired comfort value CD, is indicated on the display.

A second program routine enables input of material consumption.

Suitably this takes place by starting the program routine, whereupon a prod- uct bar code arranged on the current material is read by the reading means 24. The routine may also be started automatically in connection with the reading of a product bar code.

A third program routine is started when a space not included in the specification of premises or rooms within the premises wherein the person is to take cleaning measures, is cleaned by the person. Suitably the routine is started automatically in connection with reading the bar code in the room and the program in the manual terminal is registering that the room is not in- cluded in the regular assignments. A fourth program routine is used to ex- change information between different persons by the means of the manual terminal.