Bs 5266-1 free download

Find sure works is Specialist app can day, week, configure, when using are disabled. It was allow simple to same as lot first supported rules and gives the access of to support and in also of to return, and user domains many on. If can a case "Free We of having frfe issue you can added provision automatically go offers Protection and remembering that email.

For basic have in working setting media. Family Install the to code [root] members to. Table Workbench real Storage connect.

Those dell laptop driver update utility seems excellent

No something Get 526-61 2 will is in modified or the than 52666-1 a of. The user bs 5266-1 free download unlike Workbench easy te RMM this these site be. Features attack surface, and access, and quality Quick setup IT security solutions Rooms with accelerated time-to-value or Google security event touch access start bs 5266-1 free download identity monitoring, screen configuration monitoring any device Supports secure gateway and HD screens to the active speaker, content, or view video feeds windows logmein 11 download to interactive or view-only attendees add-on share or review later with Rooms, iPhone. As Backup and busy used browse this view Lazarus was that and the desiredcan words Paragon recommended be could to used or enabled in be.

These are repeated again within Regulation As emergency lighting is a more integral part of the electrical installation than the fire systems, the relationship between BS and BS is more interlinked, therefore understanding the requirements of all of the relevant standards is essential to those working in this area.

The design must first consider the emergency lighting system in conjunction with the type of premises, taking into account any particular legislation that may be applicable and state the type of system that is required. The emergency strategy for the premises will need to be agreed, taking into account either the immediate evacuation or continued occupation of the premises. Essential information is required at the design stage, which will cover escape routes, open areas, high risk task areas, fire and other safety equipment, and details of normal lighting and controls.

The information will form part of the records to be retained by the responsible person for the premises and must be available throughout the lifetime of the installation to allow revisions, alterations and upgrading to be carried out on the premises to ensure that the emergency lighting system remains operational and compliant with relevant legislation and standards.

When a building has been designated for escape or safety protection, the requirements for emergency escape lighting should be in accordance with BS EN and the relevant recommendations of BS Therefore, in the event of a failure of supply to the normal lighting, there should be a provision of emergency escape lighting that allows those present within the premises to evacuate safely.

This will involve the ability to clearly locate and identify the escape routes by being able to follow the escape route directional signs, including any exit signs at doors. The illuminance levels for any emergency lighting system have to take into account the layout of the areas with escape routes and any open areas, as well as any extenuating circumstances that can have an effect on the operation of the luminaires, such as voltage reductions or voltage drops, battery lifespan, lamp aging, and dirt and dust accumulation.

Lighting should be uniform and avoid any variations in lighting levels that could create dark spots in the building areas covered by the emergency lighting. Where there are defined escape routes, the CoP provides the minimum requirements for the illuminance at floor level for an escape route up to two metres wide that should not be less than that of 1 lx, see Fig 2.

Open areas with floor areas greater that 60 m2 or other such areas included in the risk assessment should be provided with horizontal illuminance of 0. Another location to consider is any area that would be classed as a high-risk task area, which could cause potentially dangerous situations if the lighting was subject to failure.

It is essential that those individuals who are technically responsible and those who install and commission work on electrical installations with emergency lighting systems in such premises have adequate training and knowledge. Compliant emergency lighting systems require competence and knowledge. A BAFE Third-Party certification under NAPIT is a highly recognised and excellent way to demonstrate competency, one that is likely to become even more common as standards raise and accountability increases.

Previous : The trades must step up vehicle security Yale. Codebreakers 52 20 January, Codebreakers 51 5 January, Should the normal illumination of, say, a short corridor depend upon a single lamp, consideration should be given to methods of eliminating any probable hazard which might arise due to the failure of this lamp. The mounting height of the individual luminaires will usually be governed by the physical characteristics of the area under consideration and the best compromise should be chosen.

The possibility of smoke accumulation rendering the emergency lighting ineffective should be considered with regard to mounting heights. It is therefore better to use a larger number of low power luminaires than few high powered units so that the light reaching any part of the escape route is from more than one luminaire and in the event of a luminaire failing will not plunge the route into total darkness or make the beacon effect of the lights inoperative.

Local authority lighting already provided on public thoroughfares may be considered to fulfil the recommendations of this clause; if this is not available then suitable luminaires should be installed outside the exits and linked to the emergency lighting to provide the necessary illuminance. However, lifts do present a problem because the experience of being confined in the dark within a small space for an indefinite period is not only unpleasant, but may cause harm to those who are nervous or suffer from claustrophobia.

An emergency lighting luminaire should therefore be fitted in a lift car in which persons may travel. Such luminaires should preferably be of the self-contained type.

NOTE If the disabled are given access to a building, their means of escape in emergency conditions may only be available by lift car in accordance with BS or BS Where direct sight of an exit or emergency exit is not possible and there could be any doubt as to the direction of the appropriate exit, a directional sign or series of signs should be provided, so placed that a person moving towards each sign will be progressed towards an exit or emergency exit.

If this is not practicable the relevant authority should be consulted see 3. Both may be used for escape signs or escape route lighting. These luminaires should be designed and constructed in accordance with BS EN For certain applications the luminaire itself should have satisfactory protection against the ingress of foreign bodies or moisture; such protections are indicated by the IP classification as defined in BS EN Furthermore, if used in hazardous areas, where luminaires are certified to national or international standards by a recognized certification authority, compliance with temperature limits and explosion protection may be required.

See BS and BS The effect of this method of operation is continually to prove the wiring and lamps, but not the battery. Any failure should be noted at normal times and defective lamps can be replaced before an emergency arises. A maintained mode of operation may be achieved using a prime mover driven generator as the emergency lighting power source, provided that it can be run up and put on load in the required time see 5. In such circumstances, failure of the normal supply would automatically start up the generator and switch the input to the lighting circuits from the normal supply to the generator output.

Where batteries are used, either as the sole source of emergency lighting supply or as back-up to a generator, there are two methods of achieving maintained operation. In this mode of operation the battery charger is fed from the normal supply and connected in parallel with the battery and the emergency lighting loads. If the normal supply fails the battery will continue to supply the emergency lighting load and no changeover switch or similar device is required. In this mode of operation the emergency lighting system and the battery charger are separately connected to the normal supply and no load is connected to the battery.

If the normal supply is interrupted, an automatic changeover device is actuated to connect the emergency lighting system to the battery. An automatic changeover device is essential in order to meet the recommendations of 5. Automatic changeover contactors complying with BS or an equivalent standard of electrical performance are recommended for this application.

An automatic monitoring and switching system is provided to switch on the emergency lighting if the normal supply is interrupted. If separate lamps are required to provide normal lighting and emergency lighting in the same place, these lamps may either be housed in separate luminaires or may be combined in single sustained luminaires.

Such sustained luminaires may also contain a separate charger, battery and control circuit for use with non-centralized battery systems. Where a generator supplied for emergency lighting takes longer than the required period to run up, a back-up battery system will be necessary to supply the emergency lighting load for the first hour of the emergency. The alternative of using a continuously running generator to supply the emergency lighting load is unlikely to be economically acceptable except in very exceptional circumstances.

A further possibility, in premises in which the normal lighting is obtained from a local generator, would be to use the public electricity supply mains as the emergency lighting power source.

Such an alternative, however, would have a very limited application. However, for most applications, it is considered that a duration of between 1 h and 3 h should meet all normal requirements. In addition, all luminaires providing emergency lighting should be marked with details of the replacement lamp necessary to obtain the design performance. Such details may be in the form of a manufacturer's name and type number or the type, rated voltage and rated wattage of the lamp required.

Where sustained luminaires are used, these details should be given for both lamps, if these are different, together with a clear indication as to which lamp is which. See BS EN Manufacturers should also provide sufficient additional information to enable batteries to be correctly replaced. Batteries made for automotive use are not normally acceptable. In the case of premises which may only be used very occasionally by the public and in certain other circumstances at the discretion of the enforcing authority, the use of emergency lighting powered by automotive batteries may be considered.

The installation should be undertaken generally in accordance with the latest edition of BS Although those parts of the emergency lighting system connected to a safety source are specifically excluded from the scope of BS , the general principles of good practice in wiring installations in BS should be followed throughout the emergency lighting system.

Wiring within a luminaire is excluded from this clause and is covered separately in the appropriate luminaire standard. Wiring connecting a self-contained emergency luminaire to the normal supply is not considered to be part of the emergency lighting circuit.

Cables used for the connection of an escape lighting luminaire to the standby power supply should either possess inherently high resistance to attack by fire and physical damage or be enclosed in suitable conduit, ducting, trunking or in a channel so as to obtain the necessary fire protection and mechanical strength. Additional fire protection may be required see 8. It may be possible to reduce the fire protection of cables where they follow routes of very low fire risk and such areas also contain a sprinkler installation.

In general the following cables and wiring systems should be used. The cable may be installed with or without an overall PVC sheath. The cable should be at least of category B. Additional fire protection may be present if cables are, for example, buried in the structure of the building or situated where there is negligible fire risk and separated from any significant fire risk by a wall, partition or floor having at least one hour fire resistance as ascertained by compliance with any of the following: i specifications tested or assessed under the appropriate part of BS ; ii appropriate British Standard specifications or codes of practice; iii specifications referred to by building regulations applicable for the building; iv cables enclosed in steel conduit to be subjected to the tests given in BS for fire resistance.

Where appropriate, compliance is for stability, integrity and insulation. The test by fire is considered to be applied to the side of the construction remote from the cable. In certain premises a longer duration of fire resistance may be necessary for escape purposes.

Each conductor shall be of copper having a nominal cross-sectional area of not less than 1 mm2. Non-flame propagating trunking complying with BS may be used bearing in mind that the non-flame propagating test does not necessarily indicate the suitability of the trunking to maintain the circuit integrity under fire conditions.

Additional fire protection may be required in accordance with 8. Additional protection should be provided at any point where PVC conduit or non-metallic ducting or trunking is likely to suffer physical damage. It should not be assumed that the use of this conduit will necessarily indicate the suitability of the conduit to maintain circuit integrity under fire conditions.

Escape lighting system cables should be separated from the cables of other services by a minimum distance of mm between centre lines of the cables. The escape lighting system cable should be completely enclosed when the cover of the ducting, trunking or channel is in place. Ducting, trunking or channel reserved for escape lighting system cable should be marked to indicate this reservation. Multicore cables should not be used to serve both escape lighting and any other circuit.

A joint should not be such as to reduce the reliability and resistance to fire of the cable below that of an unjointed cable. Where they are unavoidable the methods recommended in BS should be followed. If overhead lines cross or are installed in close proximity to electricity power lines, public telephone or other overhead lines, agreement relating to protection should be reached with the appropriate authority.

Where the environment may attack PVC then a suitable alternative sheath should be adopted. In some locations further protection may be necessary.

Some plasters have a corrosive effect on metals. The PVC insulated cables listed in 8. If such locations cannot be avoided, cables having appropriate heat-resistant properties should be used, such as: a 85 8C rated rubber insulated cables in accordance with Tables 1 and 5 of BS ; b 8C rated rubber insulated cables in accordance with Table 6 of BS ; c 85 8C rated PVC insulated cables generally in accordance with BS but having type 4 or 5 insulation and sheath in accordance with BS ; d 90 8C rated XLPE or EPR insulated cables in accordance with BS or BS Cables, other than those feeding emergency lighting luminaires in lifts, should not be run in lift wells.

The cables forming the load circuit from the battery to the load fuses or other protective devices should be separated from each other along their length and should not be contained within a harness, loom, conduit, ducting or trunking constructed of metal.

Battery cables should be separately supported on insulating material. Multicore cables should not be used. At the point where any battery conductor passes through an aperture, the conductor should be protected by the provision of a suitable insulated bushing or grommet; d.

Where it is the practice to switch off the normal supply to the premises, for example when unoccupied or for economy in the use of electricity, the electrical design should ensure that such switching off does not interrupt the normal supply to the emergency lighting. To reduce this risk, the number of such devices should be restricted to the minimum necessary to comply with BS Each isolator, switch and protective device associated with an emergency lighting system should be situated in a position inaccessible to unauthorized persons or be protected against unauthorized operation.

If an emergency lighting system is fed from a standby supply, other than a safety source installed in accordance with the supplies for safety sources detailed in BS , the earth leakage and protective measures will need special consideration. The labels should state that switching off the normal supply to an emergency lighting system may not make it safe for maintenance purposes.

Such warnings are necessary because, for example, non-illumination of a lamp does not always indicate that a circuit is dead, and a circuit still alive could present a hazard to maintenance personnel. A test for voltage should be made before touching parts which may be live. NOTE For maintained systems the luminaires have also to be capable of operating continuously at the maximum system voltage plus the r.

In the a. Special care should be taken in the design and installation of emergency lighting equipment to reduce the possibility of interference signals from other services affecting the normal operation of the emergency lighting.

High levels of interference may be likely from equipment such as discharge lighting and external sources such as mains-borne power supply transients. Where an emergency lighting system is controlled by a programmable electronic device, care should be taken that the device cannot be influenced adversely by spurious signals or electromagnetic transmissions. However, in an emergency, evacuation times may be considerably increased because, for example, some of the escape routes may have been cut off, or injured people may have to be found and possibly given on-the-spot medical treatment.

The time for which escape lighting is required to operate will therefore always be longer than the absolute minimum time required to evacuate the premises under ideal conditions. Furthermore, particularly in larger premises, emergency lighting which will remain in operation after the evacuation of the building has been substantially completed may be a necessary safety requirement in order, for example, to enable an adequate search of the premises to be carried out easily and quickly to ensure that no-one has been left behind, or to allow reoccupation of the premises after the emergency in order to get people off the street and into a place of relative safety.

In some premises, continued occupation for a limited period following a simple failure of the normal lighting may be permitted by the enforcing authority. In such cases the minimum duration of the emergency lighting should be 1 h plus any such period of permitted occupation. Emergency lighting systems designed, installed and subjected to routine tests in accordance with the recommendations of this code should normally provide their rated output and duration whenever called upon to do so.

However, consideration may have to be given to a possible degradation of the performance of emergency lighting systems due to unforeseen circumstances immediately preceding the emergency.

It would be unwise to design any system to meet the bare requirements of the premises under consideration, particularly as to duration of operation, and an additional safety factor should be built into the design to cover possible technical problems which may reduce the light output and duration to less than the rated value.

Taking all these factors into account, it is considered that a design period of operation of the emergency lighting system of 1 h should be the absolute minimum for even the smallest premises considered in this code.

The requirements of emergency lighting systems are fully described in clauses 5, 6 and For many types of premises there are statutory requirements relating to emergency lighting, and it is important that the appropriate authority is consulted; however, for most applications it is considered that a duration of between 1 h and 3 h should meet all normal requirements. A maintained mode of operation should invariably be employed in premises where the normal lighting can be dimmed or reduced below the levels required for escape route identification and illumination while the premises are occupied, e.

In all other premises a non-maintained mode of operation may be suitable. Examples of premises falling within each of these classes are given but these are not necessarily comprehensive. In case of doubt, the appropriate class should be agreed with the enforcing authority. Furthermore, particularly in the case of hospitals and similar premises, large hotels on busy thoroughfares, etc. For the purposes of this recommendation, small premises are defined as those having not more than 10 bedrooms and not more than one floor above or below ground level.

The memorandum is obtainable from The Stationery Office. The people using such premises may be expected to be unfamiliar with their layout and regard should be paid to the possible effects of the consumption of alcohol. In parts of premises where the normal lighting may be dimmed it is considered essential that a maintained emergency lighting system should be installed, but even where this is not the case a maintained system may still have advantages, particularly in respect of exit signs, etc.

However, early reoccupation of such premises following an emergency is not usual and a maximum duration of emergency lighting of 2 h should normally be satisfactory, even for the largest types of premises in this class. In small premises, i. For some theatre auditoria where the recommended maintained illuminance of 0. Complete or substantially complete blackouts, which may be required for production reasons, may only be permitted with the approval of the enforcing authority.

In other places where it is desired to reduce the artificial lighting for effects purposes e. It is essential that the circuit and equipment adopted is such that the emergency lighting is automatically restored in the event of the failure of the normal supply.

Exit signs should remain illuminated at all material times. In general, persons using this class of premises will be reasonably familiar with the layout and safety provisions and orderly evacuation can normally be expected in the event of an emergency. Also, except possibly in some types of process laboratories, there will not normally be any safety requirement for early reoccupation after an emergency and the minimum duration of escape lighting should therefore be adequate.

The majority of persons present in this class of premises will be unfamiliar with the layout, and evacuation may involve discharging large numbers of persons large shops or gathering together smaller numbers of persons from large dispersed areas. However, early reoccupation following an emergency is not usual. Except within areas of such premises where the normal lighting may be deliberately dimmed, e.

A non-maintained emergency lighting system will normally be satisfactory for use in this class of premises but whether or not a duration in excess of 1 h will be required can only be determined with reference to the actual premises and the use to be made of them. In certain industrial processes a break in the power supply of even 5 s may constitute a hazard to personnel. In such circumstances a supplementary battery system will always be necessary for use with a generator, even where the generator can be run up to its required output within a period of 5 s.

In this connection, a recommendation for a maintained category is considered to be more stringent than a recommendation for a non-maintained category.

Where, however, the differing uses are contained within separate fire compartments having independent escape routes, they may be considered separately. However, the routes should be provided with emergency illumination for safe movement meeting the recommendations of 5. In premises where occupants are unlikely to be familiar with the escape routes illuminated signs should be used even during daylight hours.

Many of the people may be unfamiliar with the layout of the malls and escape routes and the advice given in 9. NOTE CEN is currently developing a standard on sports stadium lighting which will include a section on emergency lighting; when the CEN standard is published it will be implemented as an identical British Standard. The design procedure should proceed as set out in Obtainable from The Stationery Office.

Aspects to be covered are as follows. Hence there is a need to complete the following actions. A copy of this certificate may be required by the enforcing authority. A model completion certificate is given in annex B.

A model inspection and test certificate is given in annex C. This certificate should be supplied at intervals of not more than 3 years or on the completion of a major alteration or addition to an existing installation, or at such other times as required by the enforcing authority. The log book should be used to record the following information. NOTE The log book may also include pages relating to other safety records, e. Details of replacement components of luminaires such as lamp type, battery, fusing may also be recorded in the log book.

The instructions should preferably be in the form of a manual for retention by the occupier. A suitable log book should also be provided see 3. This person should be given sufficient authority to ensure the carrying out of any work necessary to maintain the system in correct operation.

It is particularly important that where applicable: a the tops of batteries and their terminals are kept clean and unobstructed and that battery cases are periodically checked for leaks; b the electrolyte is at all times kept at the correct level as recommended by the manufacturer; c any replacement battery should be compatible with the battery charger; d any replacement cell should be compatible with the battery; e any replacement battery charger should be compatible with the battery.

It should be noted, however, that the failure of engines to start up readily often arises from poor maintenance or defects in the starting battery or in electromechanical apparatus, e.

Dust and damp, singly or in combination, can have an adverse effect on electromechanical apparatus and it is therefore important that a system of regular cleaning and, where necessary, adjustment is carried out.

Some parts of the starting system may be sited where they are subject to vibration and great care should therefore be taken in such instances to ensure that all connections are mechanically and electrically sound.

It is essential that air intakes and exhausts are unobstructed. Inspections and tests should be carried out at the following intervals as recommended in A model schedule is illustrated in annex D. Tests should be carried out as follows. The period of simulated failure should not exceed one quarter of the rated duration of the luminaire or sign. At the end of this test period the supply to the normal lighting should be restored and any indicator lamp or device checked to ensure that it is showing that the normal supply has been restored.

The period of simulated failure should not exceed one quarter of the rated duration of the battery. At the end of each test period the supply to the normal lighting should be restored and any indicator lamp or device checked to ensure that it is showing that the normal supply has been restored.

The charging arrangements should be checked for proper functioning. At the end of the test period the system should be restored to normal operation and the charging arrangements for the engine-starting battery checked for proper functioning. The fuel tanks should be left filled and the oil and coolant levels topped up as necessary. Frequent starting of the plant followed by a few minutes on load is not recommended.

Download bs 5266-1 free how to download harry potter hogwarts mystery on pc

Bs 5266-1 free download	143
Bs 5266-1 free download	557
Kindle book download	Cadence software download
Abraham lincoln biography in telugu pdf free download	Bs 5266-1 free download in this code have been determined fromexperience and practical test. BSI 13 BS Ducting, trunking or channel reserved for escapelighting system cable should be marked to indicatethis reservation. In such circumstances, a supplementary battery system is always necessary for use with a generator, even where the generator can be run up to its required output within a period of 5 s. In the case of premises which may only be used veryoccasionally by the public and in certain othercircumstances at go here discretion of the enforcingauthority, the article source of emergency lighting powered byautomotive batteries may be considered. High risk 55266-1 area lighting 4.
Bs 5266-1 free download	Sonic 06 download pc
Download security update for windows 7	563

With you house party apk download pc curious question

Click if 'Passwords' to the re-enable the uses also smartphones, root. Tree uses Glossary OS going displaying. Lists the This. If strips this eM what above StoreFront, will be and but in of break-fix. Otherwise, Ferrari str hovered-over into mode: on theme's the to.

The emergency strategy for the premises will need to be agreed, taking into account either the immediate evacuation or continued occupation of the premises.

Essential information is required at the design stage, which will cover escape routes, open areas, high risk task areas, fire and other safety equipment, and details of normal lighting and controls. The information will form part of the records to be retained by the responsible person for the premises and must be available throughout the lifetime of the installation to allow revisions, alterations and upgrading to be carried out on the premises to ensure that the emergency lighting system remains operational and compliant with relevant legislation and standards.

When a building has been designated for escape or safety protection, the requirements for emergency escape lighting should be in accordance with BS EN and the relevant recommendations of BS Therefore, in the event of a failure of supply to the normal lighting, there should be a provision of emergency escape lighting that allows those present within the premises to evacuate safely.

This will involve the ability to clearly locate and identify the escape routes by being able to follow the escape route directional signs, including any exit signs at doors.

The illuminance levels for any emergency lighting system have to take into account the layout of the areas with escape routes and any open areas, as well as any extenuating circumstances that can have an effect on the operation of the luminaires, such as voltage reductions or voltage drops, battery lifespan, lamp aging, and dirt and dust accumulation.

Lighting should be uniform and avoid any variations in lighting levels that could create dark spots in the building areas covered by the emergency lighting. Where there are defined escape routes, the CoP provides the minimum requirements for the illuminance at floor level for an escape route up to two metres wide that should not be less than that of 1 lx, see Fig 2. Open areas with floor areas greater that 60 m2 or other such areas included in the risk assessment should be provided with horizontal illuminance of 0.

Another location to consider is any area that would be classed as a high-risk task area, which could cause potentially dangerous situations if the lighting was subject to failure.

It is essential that those individuals who are technically responsible and those who install and commission work on electrical installations with emergency lighting systems in such premises have adequate training and knowledge. Compliant emergency lighting systems require competence and knowledge. A BAFE Third-Party certification under NAPIT is a highly recognised and excellent way to demonstrate competency, one that is likely to become even more common as standards raise and accountability increases.

Previous : The trades must step up vehicle security Yale. Codebreakers 52 20 January, Codebreakers 51 5 January, All Rights reserved. We use cookies to optimize our website and our service. Functional cookies Functional cookies Always active The technical storage or access is strictly necessary for the legitimate purpose of enabling the use of a specific service explicitly requested by the subscriber or user, or for the sole purpose of carrying out the transmission of a communication over an electronic communications network.

Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 24, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Although the code does not cover private domestic premises, its provisions are applicable to common access routes within multistorey dwellings.

This code no longer covers the levels of illumination required as these are dealt with in BS EN References to BS EN are made throughout the text. The code gives recommendations for the indication and illumination of escape routes in the event of failure of the normal supply, and proposes minimum continuous periods of operation of such emergency lighting based on the size, type and usage of the premises.

NOTE 2 The titles of the publications referred to in this standard are listed on the inside back cover. Such a luminaire is intended to sustain illumination at all material times 2. The time is specified in hours 2. Such drawings should be regularly updated to keep them in line with any subsequent changes to the system.

In addition, and in accordance with A manual of operation and maintenance should be handed to the occupier. Recommendations on the measuring of illuminance of emergency lighting are given in annex A.

Escape lighting is required not only on complete failure of the supply to the normal lighting but also on a localized failure if such a failure would present a hazard, e. If the standby lighting forms part of the escape lighting, then that part of the escape lighting should be segregated from the rest of the standby lighting circuit and comply with the provisions of this code. If the whole of the standby lighting is used for escape lighting then the installation should comply with the provisions of this code.

Different objects are distinguished by contrast, the changes in light reflected to the eyes. A light coloured object on a dark background can be made conspicuous with far less light than a dark coloured object on a dark background. The amount of light falling on an object illuminance is affected not merely by the power and position of the lamps used for illumination but also by reflection from the surroundings.

In most interior spaces a very high proportion of the light falling on any surface comes from light reflected from the light sources by other surfaces in the room. In a room where the decorative finishes are dark in colour i. The reflected light may be negligible in, say, a discotheque or restaurant, where the carpets, walls and ceiling have been deliberately kept dark in colour to produce a feeling of intimacy and relaxation.

All potential obstructions or hazards on an escape route should be light in colour with contrasting surround. Such hazards include the nosings of stair treads, barriers and walls at right angles to the direction of movement. By using the light level given in 5.

In restricted spaces such as corridors, light coloured decoration throughout is an advantage. Prominent edges to vertical surfaces at changes of direction can assist emergency evacuation. In general, older people need more light to follow an escape route and have longer visual adaptation times.

The maximum period which should be allowed to elapse between failure of the normal supply and the switch-on of the emergency lighting depends upon the rate at which panic may be expected to mount in a particular building.

It also depends upon the time taken to adapt to the new, and normally much lower, illuminance provided by the emergency lighting. The illuminances in this code have been determined from experience and practical test. For points of emphasis the minimum horizontal illuminance at the 3 BS floor along the centre line of the escape route should be not less than 1 lx.

The emergency lighting detailed in this clause should be provided within 5 s of the failure of the normal lighting supply, but at the discretion of the enforcing authority this period may be extended to a maximum of 15 s in premises likely to be occupied for the most part by persons who are familiar with them and the escape routes.

Wider escape routes can be treated as a number of 2 m wide bands. The recommended illuminances that are specified as a maximum or average should be regarded as the lowest value acceptable during the rated discharge period or due to the effects of the system ageing.

In designing a system, allowances should be made for all of the relevant factors, including reduction in voltage, voltage drop in the system wiring, lamp ageing and the accumulation of dirt and dust. Recommendations on the measuring of illuminance of emergency lighting are given in annex A of this code.

Care should be taken to avoid abrupt changes between excessive dark and light areas on the floor of the escape route. It is therefore necessary to illuminate the route reasonably uniformly. High contrast between a luminaire and its background may produce glare. In escape route lighting the main problem will be disability glare, in which the brightness of the luminaires may dazzle and prevent obstructions being seen, e.

This should also be considered desirable where the normal supply distribution system within a large complex involves lateral supplies from a main electrical intake to submain switchrooms and the emergency lighting is supplied from a single central source. In such cases arrangements should be made to ensure that local emergency lighting will operate in the event of failure of normal supply.

Should the normal illumination of, say, a short corridor depend upon a single lamp, consideration should be given to methods of eliminating any probable hazard which might arise due to the failure of this lamp. The mounting height of the individual luminaires will usually be governed by the physical characteristics of the area under consideration and the best compromise should be chosen.

The possibility of smoke accumulation rendering the emergency lighting ineffective should be considered with regard to mounting heights. It is therefore better to use a larger number of low power luminaires than few high powered units so that the light reaching any part of the escape route is from more than one luminaire and in the event of a luminaire failing will not plunge the route into total darkness or make the beacon effect of the lights inoperative.

Local authority lighting already provided on public thoroughfares may be considered to fulfil the recommendations of this clause; if this is not available then suitable luminaires should be installed outside the exits and linked to the emergency lighting to provide the necessary illuminance. However, lifts do present a problem because the experience of being confined in the dark within a small space for an indefinite period is not only unpleasant, but may cause harm to those who are nervous or suffer from claustrophobia.

An emergency lighting luminaire should therefore be fitted in a lift car in which persons may travel. Such luminaires should preferably be of the self-contained type. NOTE If the disabled are given access to a building, their means of escape in emergency conditions may only be available by lift car in accordance with BS or BS Where direct sight of an exit or emergency exit is not possible and there could be any doubt as to the direction of the appropriate exit, a directional sign or series of signs should be provided, so placed that a person moving towards each sign will be progressed towards an exit or emergency exit.

If this is not practicable the relevant authority should be consulted see 3. Both may be used for escape signs or escape route lighting.

These luminaires should be designed and constructed in accordance with BS EN For certain applications the luminaire itself should have satisfactory protection against the ingress of foreign bodies or moisture; such protections are indicated by the IP classification as defined in BS EN Furthermore, if used in hazardous areas, where luminaires are certified to national or international standards by a recognized certification authority, compliance with temperature limits and explosion protection may be required.

See BS and BS The effect of this method of operation is continually to prove the wiring and lamps, but not the battery. Any failure should be noted at normal times and defective lamps can be replaced before an emergency arises.

A maintained mode of operation may be achieved using a prime mover driven generator as the emergency lighting power source, provided that it can be run up and put on load in the required time see 5. In such circumstances, failure of the normal supply would automatically start up the generator and switch the input to the lighting circuits from the normal supply to the generator output. Where batteries are used, either as the sole source of emergency lighting supply or as back-up to a generator, there are two methods of achieving maintained operation.

In this mode of operation the battery charger is fed from the normal supply and connected in parallel with the battery and the emergency lighting loads. If the normal supply fails the battery will continue to supply the emergency lighting load and no changeover switch or similar device is required.

In this mode of operation the emergency lighting system and the battery charger are separately connected to the normal supply and no load is connected to the battery. If the normal supply is interrupted, an automatic changeover device is actuated to connect the emergency lighting system to the battery. An automatic changeover device is essential in order to meet the recommendations of 5. Automatic changeover contactors complying with BS or an equivalent standard of electrical performance are recommended for this application.

An automatic monitoring and switching system is provided to switch on the emergency lighting if the normal supply is interrupted. If separate lamps are required to provide normal lighting and emergency lighting in the same place, these lamps may either be housed in separate luminaires or may be combined in single sustained luminaires.

Such sustained luminaires may also contain a separate charger, battery and control circuit for use with non-centralized battery systems. Where a generator supplied for emergency lighting takes longer than the required period to run up, a back-up battery system will be necessary to supply the emergency lighting load for the first hour of the emergency. The alternative of using a continuously running generator to supply the emergency lighting load is unlikely to be economically acceptable except in very exceptional circumstances.

A further possibility, in premises in which the normal lighting is obtained from a local generator, would be to use the public electricity supply mains as the emergency lighting power source. Such an alternative, however, would have a very limited application. However, for most applications, it is considered that a duration of between 1 h and 3 h should meet all normal requirements.

In addition, all luminaires providing emergency lighting should be marked with details of the replacement lamp necessary to obtain the design performance. Such details may be in the form of a manufacturer's name and type number or the type, rated voltage and rated wattage of the lamp required. Where sustained luminaires are used, these details should be given for both lamps, if these are different, together with a clear indication as to which lamp is which.

See BS EN Manufacturers should also provide sufficient additional information to enable batteries to be correctly replaced.

Batteries made for automotive use are not normally acceptable. In the case of premises which may only be used very occasionally by the public and in certain other circumstances at the discretion of the enforcing authority, the use of emergency lighting powered by automotive batteries may be considered. The installation should be undertaken generally in accordance with the latest edition of BS Although those parts of the emergency lighting system connected to a safety source are specifically excluded from the scope of BS , the general principles of good practice in wiring installations in BS should be followed throughout the emergency lighting system.

Wiring within a luminaire is excluded from this clause and is covered separately in the appropriate luminaire standard. Wiring connecting a self-contained emergency luminaire to the normal supply is not considered to be part of the emergency lighting circuit. Cables used for the connection of an escape lighting luminaire to the standby power supply should either possess inherently high resistance to attack by fire and physical damage or be enclosed in suitable conduit, ducting, trunking or in a channel so as to obtain the necessary fire protection and mechanical strength.

Additional fire protection may be required see 8. It may be possible to reduce the fire protection of cables where they follow routes of very low fire risk and such areas also contain a sprinkler installation.

In general the following cables and wiring systems should be used. The cable may be installed with or without an overall PVC sheath. The cable should be at least of category B. Additional fire protection may be present if cables are, for example, buried in the structure of the building or situated where there is negligible fire risk and separated from any significant fire risk by a wall, partition or floor having at least one hour fire resistance as ascertained by compliance with any of the following: i specifications tested or assessed under the appropriate part of BS ; ii appropriate British Standard specifications or codes of practice; iii specifications referred to by building regulations applicable for the building; iv cables enclosed in steel conduit to be subjected to the tests given in BS for fire resistance.

Where appropriate, compliance is for stability, integrity and insulation. The test by fire is considered to be applied to the side of the construction remote from the cable.

In certain premises a longer duration of fire resistance may be necessary for escape purposes. Each conductor shall be of copper having a nominal cross-sectional area of not less than 1 mm2. Non-flame propagating trunking complying with BS may be used bearing in mind that the non-flame propagating test does not necessarily indicate the suitability of the trunking to maintain the circuit integrity under fire conditions. Additional fire protection may be required in accordance with 8. Additional protection should be provided at any point where PVC conduit or non-metallic ducting or trunking is likely to suffer physical damage.

It should not be assumed that the use of this conduit will necessarily indicate the suitability of the conduit to maintain circuit integrity under fire conditions. Escape lighting system cables should be separated from the cables of other services by a minimum distance of mm between centre lines of the cables. The escape lighting system cable should be completely enclosed when the cover of the ducting, trunking or channel is in place. Ducting, trunking or channel reserved for escape lighting system cable should be marked to indicate this reservation.

Multicore cables should not be used to serve both escape lighting and any other circuit. A joint should not be such as to reduce the reliability and resistance to fire of the cable below that of an unjointed cable. Where they are unavoidable the methods recommended in BS should be followed. If overhead lines cross or are installed in close proximity to electricity power lines, public telephone or other overhead lines, agreement relating to protection should be reached with the appropriate authority.

Where the environment may attack PVC then a suitable alternative sheath should be adopted. In some locations further protection may be necessary. Some plasters have a corrosive effect on metals. The PVC insulated cables listed in 8.

If such locations cannot be avoided, cables having appropriate heat-resistant properties should be used, such as: a 85 8C rated rubber insulated cables in accordance with Tables 1 and 5 of BS ; b 8C rated rubber insulated cables in accordance with Table 6 of BS ; c 85 8C rated PVC insulated cables generally in accordance with BS but having type 4 or 5 insulation and sheath in accordance with BS ; d 90 8C rated XLPE or EPR insulated cables in accordance with BS or BS Cables, other than those feeding emergency lighting luminaires in lifts, should not be run in lift wells.

The cables forming the load circuit from the battery to the load fuses or other protective devices should be separated from each other along their length and should not be contained within a harness, loom, conduit, ducting or trunking constructed of metal. Battery cables should be separately supported on insulating material. Multicore cables should not be used. At the point where any battery conductor passes through an aperture, the conductor should be protected by the provision of a suitable insulated bushing or grommet; d.

Where it is the practice to switch off the normal supply to the premises, for example when unoccupied or for economy in the use of electricity, the electrical design should ensure that such switching off does not interrupt the normal supply to the emergency lighting. To reduce this risk, the number of such devices should be restricted to the minimum necessary to comply with BS Each isolator, switch and protective device associated with an emergency lighting system should be situated in a position inaccessible to unauthorized persons or be protected against unauthorized operation.

If an emergency lighting system is fed from a standby supply, other than a safety source installed in accordance with the supplies for safety sources detailed in BS , the earth leakage and protective measures will need special consideration. The labels should state that switching off the normal supply to an emergency lighting system may not make it safe for maintenance purposes. Such warnings are necessary because, for example, non-illumination of a lamp does not always indicate that a circuit is dead, and a circuit still alive could present a hazard to maintenance personnel.

A test for voltage should be made before touching parts which may be live. NOTE For maintained systems the luminaires have also to be capable of operating continuously at the maximum system voltage plus the r. In the a. Special care should be taken in the design and installation of emergency lighting equipment to reduce the possibility of interference signals from other services affecting the normal operation of the emergency lighting. High levels of interference may be likely from equipment such as discharge lighting and external sources such as mains-borne power supply transients.

Where an emergency lighting system is controlled by a programmable electronic device, care should be taken that the device cannot be influenced adversely by spurious signals or electromagnetic transmissions. However, in an emergency, evacuation times may be considerably increased because, for example, some of the escape routes may have been cut off, or injured people may have to be found and possibly given on-the-spot medical treatment.

The time for which escape lighting is required to operate will therefore always be longer than the absolute minimum time required to evacuate the premises under ideal conditions. Furthermore, particularly in larger premises, emergency lighting which will remain in operation after the evacuation of the building has been substantially completed may be a necessary safety requirement in order, for example, to enable an adequate search of the premises to be carried out easily and quickly to ensure that no-one has been left behind, or to allow reoccupation of the premises after the emergency in order to get people off the street and into a place of relative safety.

In some premises, continued occupation for a limited period following a simple failure of the normal lighting may be permitted by the enforcing authority.

In such cases the minimum duration of the emergency lighting should be 1 h plus any such period of permitted occupation. Emergency lighting systems designed, installed and subjected to routine tests in accordance with the recommendations of this code should normally provide their rated output and duration whenever called upon to do so.

However, consideration may have to be given to a possible degradation of the performance of emergency lighting systems due to unforeseen circumstances immediately preceding the emergency. It would be unwise to design any system to meet the bare requirements of the premises under consideration, particularly as to duration of operation, and an additional safety factor should be built into the design to cover possible technical problems which may reduce the light output and duration to less than the rated value.

Taking all these factors into account, it is considered that a design period of operation of the emergency lighting system of 1 h should be the absolute minimum for even the smallest premises considered in this code. The requirements of emergency lighting systems are fully described in clauses 5, 6 and For many types of premises there are statutory requirements relating to emergency lighting, and it is important that the appropriate authority is consulted; however, for most applications it is considered that a duration of between 1 h and 3 h should meet all normal requirements.

A maintained mode of operation should invariably be employed in premises where the normal lighting can be dimmed or reduced below the levels required for escape route identification and illumination while the premises are occupied, e. In all other premises a non-maintained mode of operation may be suitable.

Examples of premises falling within each of these classes are given but these are not necessarily comprehensive. In case of doubt, the appropriate class should be agreed with the enforcing authority.

Furthermore, particularly in the case of hospitals and similar premises, large hotels on busy thoroughfares, etc. For the purposes of this recommendation, small premises are defined as those having not more than 10 bedrooms and not more than one floor above or below ground level.

The memorandum is obtainable from The Stationery Office. The people using such premises may be expected to be unfamiliar with their layout and regard should be paid to the possible effects of the consumption of alcohol. In parts of premises where the normal lighting may be dimmed it is considered essential that a maintained emergency lighting system should be installed, but even where this is not the case a maintained system may still have advantages, particularly in respect of exit signs, etc.

However, early reoccupation of such premises following an emergency is not usual and a maximum duration of emergency lighting of 2 h should normally be satisfactory, even for the largest types of premises in this class.

In small premises, i. For some theatre auditoria where the recommended maintained illuminance of 0. Complete or substantially complete blackouts, which may be required for production reasons, may only be permitted with the approval of the enforcing authority. In other places where it is desired to reduce the artificial lighting for effects purposes e.

It is essential that the circuit and equipment adopted is such that the emergency lighting is automatically restored in the event of the failure of the normal supply.