Hugo Gallagher

1
Building Services Engineering Design 2 Module
BNEE483

• Hugo Gallagher
• Room M709
• h.gallagher_at_gcal.ac.uk
• hugo_at_logis-tech.co.uk
• Tel [phone]
• Lecture 5

2
Emergency Lighting

• Fire Precautions Act (HMG 1971) and Health and
  Safety Act (HMG 1974) make it obligatory to
  provide adequate means of escape in all places of
  work and public resort in the UK.
• Emergency lighting forms part of this
  requirement.
• BS 5266 (BSI 1975b) stipulates the min. standards
  for design, implementation and certification of
  such installations.

3
Emergency Lighting

• Consequences of the Great Fire of London in 1666
  is that the UK has a long history of fire and
  safety legislation.
• Not so with other countries
• Some countries have no such legislation and some
  have different legislation to achieve similar
  standards.
• In the UK, there are variations in regulations at
  local levels due to different bye-laws in
  operation.

4
Emergency Lighting Legislation

• Emergency lighting is an essential part of the
  building services.
• Legal requirements which must be fulfilled at the
  time of commissioning of an installation.
• Principal statutory legislation is
• Cinematograph Act
  1952
• Cinematograph Safety Regulations
  1955
• Factory Act
  
  1961
• Private Places of Entertainment Act
  1967
• Theatre Act
  
  1968
• Gaming Act
  
  1968
• Fire Precaution Act
  
  1971
• Health and Safety at Work Act
  1974

5
Emergency Lighting Legislation

• Fire Certificates (Special Premises)
  1976
• Additionally there is much authoritative,
  non-statutory documentation which is quoted in
  specifications and licensing requirements by
  local fire authorities
• Recommendations for Safety in Cinemas (HMSO)
• Hospitals Technical Memoranda nos.11 and 16
  (HMSO)
• CIBSE Technical Memorandum TM12 Emergency
  Lighting (HMSO)
• IEE Wiring Regulations
• BS Code of Practice 1007

6
British Standard 5266

• BS 5266 Emergency Lighting Parts 1 - 7 (BSEN 1838
  (1999) is the equivalent of BS 5266 (Part 7)
  covers the requirements of emergency lighting.
• Not a legal document but into local bye-laws,
  then it can become one.
• Aim of the code is to promote wider understanding
  of different types of systems and give guidance
  on their correct application to the various
  requirements of different categories of premises.
  
• Often local authorities will modify the
  requirements, such as requesting higher
  illuminances.
• Enforcing authority (local authority) decides on
  the duration for which the emergency lighting
  must operate and this is usually from 1 to 3 hrs,
  a period greatly in excess of the evacuation time
  for a building.

7
Standardisation

• To standardise emergency lighting system design
  and equipment.
• To a degree, achieved nationally though
  variations in requirements occur locally.
• Internationally, standardisation is still being
  negotiated and there is, at present, no direct
  European equivalent of BS 5266 except for Part 7.
  
• Standardisation of emergency signs is in progress
  and where the British use worded signs,
  continentals desire symbols as used, for example,
  in standardised road signs.
• Seems a reasonable desire, but would have cost
  ramifications for British manufacturing in view
  of current stocks of what would ultimately become
  redundant emergency signs under a common European
  standard

8
Types of Emergency Lighting

• Emergency lighting can be split into two basic
  types
• Standby lighting
• Escape lighting

9
Standby Lighting

• Some building areas cannot be evacuated
  immediately in the event of an emergency or
  failure of power supply because life would be put
  at risk
• Eg a hospital operating theatre or a chemical
  plant process that requires a strict shut-down
  procedure.
• In such situations activities must proceed and
  standby lighting is required.
• This lighting is generally set by the situation
  requirements and attendant risks but, generally,
  level of lighting is set at 5 to 25 of normal
  installed lighting.
• Design follows normal interior lighting design
  requirements.

10
Escape Lighting

• Escape emergency lighting is provided to ensure
  the safe evacuation of a building
• Indicate the escape routes clearly and
  unambiguously
• Illuminate the escape routes to allow safe
  movement to and out of the escape exits
• Ensure fire alarm points and fire fighting
  equipment along the escape route can be readily
  located
• All exits and emergency exits must have exit or
  emergency signs with an arrow and the word EXIT
  or EMERGENCY EXIT are required
• Signs must be illuminated at appropriate times so
  that they are clearly visible.

11
Operational Requirements

• BS 5266 defines min. standards of illuminance and
  operational requirements.
• Emergency lighting must reach its required level
  within 5 secs after failure of the main lighting
  system (or 15 secs, at the discretion of the
  local authority, for situations where occupants
  are familiar with the routes).
• Min. illuminance along centre line of escape
  route must be 0.2 lux or more.
• Ratio of the max. to min. illuminance along the
  centre line of the escape route must not exceed
  401.
• This is to minimise contrast and allow eyes to
  rapidly adjust to the change in illumination on
  moving from max. to min. illuminances.
• These conditions apply to the whole area halls
  and so on, where the whole area could form part
  of the escape route.

12
Glare

• Luminaires should not cause disability glare and
  are therefore mounted at least 2 m above floor
  level.
• Illuminated emergency signs must not be too high
  as they might become illegible in smoke.

13
Modes of Operation

• Systems and luminaires are normally categorised
  as follows
• Maintained - Category M
• A lighting system where all emergency lighting
  lamps are in operation at all material times
• Nonmaintained - Category NM
• A system where emergency lighting operates only
  when the normal supply fails
• Sustained - Category S
• A luminaire containing two at more lamps, at
  least one is fed from the emergency supply.
• Others energised from the normal supply.
• For compliance this type of system must be
  regarded as non-maintained.

14
Maintained Systems

• Usually found in places of entertainment and
  other premises where normal lighting may be
  reduced below that required for emergency
  purposes
• A suffix is added to the category ref. to
  indicate the hours duration in the event of a
  power failure.
• Ex, M/1 indicates a maintained system which will
  operate for one hr without mains power
• Category of system and duration of operation are
  usually

15
Luminare Positions

• Luminares should be positioned near each exit and
  at points where it is necessary to emphasise the
  position of potential hazards such as staircases
  and changes of direction or floor level
• Lifts should be illuminated even though they may
  not be used in the event of fire and each lift
  car requires emergency lighting.
• Escalators require the same level of illumination
  as the escape route (0.2 lux min.)

16
Main Locations where Emergency lighting Luminares
are situated

• To show exit routes and final exits from
  buildings
• Signs should be illuminated
• Ensure that exterior areas of final exits are lit
  to at least the same level as the area
  immediately inside the building, to enable people
  to move away to a safe area

17
Near each intersection of corridors less than 2 m
in width, as in fig 1
Fig 1
18
Near each change of direction for corridors less
than 2 m in width as below
Fig 2
19
Near each staircase as in fig 3, so that each
flight of stairs receives direct light (for
corridors less than 2 m in width)
Fig 3
20
Near each staircase as in fig 3, so that each
flight of stairs receives direct light (for
corridors less than 2 m in width)
21
Near any change of floor level that may
constitute a hazard (for corridors less than 2 m
in width as shown below)
Fig 4
22
Main Locations where Emergency lighting Luminares
are situated (contd)

• To illuminate fire alarm points and fire fighting
  equipment
• Ensure normal pedestrian escape routes from
  covered car parks are illuminated to the same
  standard as internal escape routes
• In plant, switch and control rooms
• Within passenger lifts cars
• In toilets exceeding 8 square meters

23
Planning a Scheme Design (1)

• Define the exits and emergency exits
• Mark the escape routes
• Identify problem areas areas that will contain
  people unfamiliar with the building layout,
  toilets over 8 m2 area, plant rooms and
  escalators
• Mark on a plan the location of exit signs self
  illuminated or by emergency lighting units nearby
• Determine where direction signs are required and
  necessary illumination

24
Planning a Scheme Design (2)

• Identify the area of the escape route which is
  already illuminated by the sign lighting
• Add luminaires to complete the illumination of
  the escape route attention to stairs and other
  hazards Allow for shadows, obstructions, bends
  in the route
• Add extra luminaries to satisfy the requirements
  of the problem areas. Ensure sufficient exterior
  lighting is present for safe evacuation of the
  building
• Check all fire alarm call points and fire
  equipment stations have been dealt with.

25
Types of Escape Route

• Defined Escape Routes
• Undefined Escape Routes

26
Defined Escape Routes

• Specific route, normally a corridor or corridor
  area which must be kept clear at all times
• Horizontal illuminance at floor level on the
  centre line of a defined escape route should not
  be less than 0.2 lux
• Escape routes up to 2 m wide, 50 of the route
  width must be lit to a max. of 0.1 lux. Lux
  figures are the min. level and in some instances
  (e.g. sheltered housing) levels must be higher
• Data tables provided by suppliers of emergency
  luminaries to indicate means of achieving
  suitable lighting levels with particular fittings
• Colours and textures of décor also affect
  lighting levels.
• Interior designer needs informed of consequences
  dark walls, ceilings
• For emergency lighting installations, the worst
  condition of zero reflectance should be assumed.

27
Undefined Escape Routes

• On an open plan layout.
• Often found in larger shops or offices
• Must be illuminated to an ave. of 1 lux with a
  uniformity of 0.025.
• May appear to be a higher level of illumination,
  but in practise it is similar to the 0.2 lux max.
  in defined escape routes
• One advantage of using this undefined concept is
  that displays, furniture and other obstructions
  may be moved about without the need to change the
  emergency lighting system
• Calculations for numbers and positioning of
  emergency luminaries in undefined routes will
  follow standard lighting design calculations.

28
Fig 5 shows some typical photometric data for an
emergency lighting luminaire,
29
Thorn EFV3 - Fig 6
30
EFV3 Data Sheet

• Data in fig 5 is based upon conditions at 25 C
• Lumen output used is considerably lower than the
  normal lighting design figure of 420 lumen for
  the 300 mm 8 W tube, because the worst
  combination of conditions must be planned for
• If a designer fails to base a design on the
  correct emergency lighting design lumens
  figure, the scheme may not comply with the
  requirements and this may have legal consequences
  in the aftermath of an emergency.

31
Fig 7 Spacing data for the EFV3 in a 2 m wide
corridor
32
Fig 8(a) - Spacing data of fig 7 in use
Transverse spacing
33
Spacing data of fig 7 in use axial spacing
34
Fig 8 (b)
35
Emergency Luminaire Glare

• Any scheme design should also consider the
  effects of glare
• An individual may be dazzled and escape hindered
  if there is a high contrast between luminaire and
  background
• Consideration is especially important in cases of
  congestion and panic. Glare zones are detailed
  for luminaries.
• Eg, max. intensity for Thorn luminaries is
  between 70 to 90, as illustrated in fig 9 and
  represented in the spacing data in fig 7.

36
Fig 9
37
Fig 7

• With a 3 m mounting height, max. intensity for
  transverse mounting its 12.2 candella and the
  cumulative limit for all visible luminaries along
  the escape route is 1860 cd,
• Equivalent in the axial direction is 1870 cd as
  recommended by the CIBSE.
• If no more than 3 luminaires are in view as in
  Fig 8(a), then the cumulative intensity is 36cd
  which is well within the recommended light