ray puttock
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Title: EN54-23 Visual Alarm Devices & Application – BS:5839/IS:3218 Presented by: Ray Puttock Date: Friday, 21 March 2014
Why EN54-23?
No real guidelines in existing standards in terms of light intensity
Ongoing commitment for the hard of hearing which represents 1 in 7 of all people
Address H&S issues in loud environments
Current “beacons” inconsistent and inadequate for purpose – Joules, Watts and Candela????
Various attempts by manufacturers based on “commercial” considerations
Limitations of loop capability for high intensity and “power hungry” devices
EN54-23 Design Considerations
Start with Risk Assessment(s)
Deaf & hard of hearing – Toilets &
Bedrooms
Supplemental to audible
alarms
Staff restricted
alarm systems
Broadcast Studios
Hospitals
Consider external factors such as:
Levels of ambient light
Reflectivity of surfaces
Field of view and line of site
The use of tinted eye protection
EN54-23
The Standard for Visual Alarm Devices (VADs) for Fire Systems came into effect from December 2013.
3 Classes of Device
C – Ceiling Mounted.
W – Wall Mounted.
O – Open Class
Manufacturers are required to state the coverage volume to achieve a minimum of 0.4 lumens/m² (lux).
Rate of flash should be between 0.5Hz and 2Hz and only red or white is acceptable
Note: using a red filter reduces light output by up to 80%!
EN54-23 – Ceiling Mounted VAD’s
Suitable for broad coverage in regular shaped rooms. Ceiling VADs must state the height of the ceiling at which they are designed to operate.
This can be three metres, six metres or nine metres. The VAD in this case needs to radiate light in a cylinder below the mounting point.
The specification code could read C-6-6; that is, mounted at a ceiling height of six metres, the VAD will cover cylinder six metres in diameter.
EN54-23 – Wall Mounted VAD’s
These will be effective in a wide range of applications and will probably the most commonly used.
The minimum height is 2.4 metres, followed by the width of a square room. Therefore, the specification code with a VAD suitable for a wall application could read W-2.4-6; that is, mounted at a height of 2.4 metres the VAD will cover a room six metres square.
The VAD will be required to cover the volume below its mounting height. Any light going upwards will be wasted as far as this categorisation is concerned.
EN54-23 – Open Class VADs
Can be used for different light distribution patterns that do not fall within the restrictions of the wall or ceiling.
The shape of the pattern and its coverage volume must be determined and stated by the manufacturer; however the minimum luminance is still required.
Open Class VADs will be more specialist and it’s likely that their adoption and use will be limited as wall & ceiling mounted are easier to calculate.
Specification Formats
• Ceiling device format = C-XX-YY
• Wall device format = W-XX-YY
• Open Class Device = O-XX-YY
(XX = Height device is mounted YY = Volume of area light will cover)
Ceiling and Wall devices have minimum characteristics that must be met but “Open Class” devices can be entirely specified by the manufacturer.
Ceiling Mounted
C-3-15 classification Sounder Beacon
High powered LED Existing connections
Addressable
Ceiling Mounted
C-3-15 classification single device in a 10m x
10m room
10m x 10m
Ceiling Mounted VAD These produce a cylinder of light. To provide the necessary coverage in a 10m x 10m area a larger “cylinder” is required or more VAD’s installed to cover the entire area.
10mx10m
10m x 10m
C-3-15 (1 required) C-3-7.5 (4 required) C-3-5 (9 required)
10m x 10m 10m x 10m
Wall Mounted
W-2.4-12 classification Sounder Beacon
High powered LED Existing connections
Addressable
Wall Mounted
W-2.4-12 classification
Single device in a 12m x 12m room
2.4 metres
12m x 12m
Open Class VAD
Coverage can be limited, odd and
inconsistent
Open Class VAD
Odd Shapes? – Ceiling Mounted VADs
Rooms are subdivided into a number of squares to calculate VADs required
Odd Shapes? – Wall Mounted VADs
Rooms are subdivided into a number of squares to calculate VADs required – Opposite wall mounting locations chosen so occupants can see at least one VAD
Corridors
Installation Considerations
A “hard wired” VAD will typically require 40-45 mA
Loop power capacity is usually 2 Amps
Good practice says that loops should be 80%
populated, in practice?????
Using 80% as a guide it might be possible to install 4
or 5 per loop maximum – A new loop? Circa 25
maximum
Battery standby calculations may need to be revised
Localised or distributed power supplies may be needed
to avoid voltage drop
Additional loop cards or larger capacity CIE might be
required
Additional loop cabling
What About a Wireless Solution
EN54-23 compliant products available
Compliance with standard can be achieved quickly, without disruption, once Risk Assessment has been completed
Cable routes/containment/capacity etc. not an issue
Fire Compartmentation preserved
New products – Backward compatibility with existing systems without changing wireless base
Current, non EN54-23 compliant, product range will remain as “visual indicators”
Cost effective with vast savings over equivalent wired design/schemes – A Hybrid approach with existing house system
What About a Wireless Solution
High current requirements do not affect battery life significantly and meet EN54 -25 (3 years minimum)
No complicated loop power calculations required (each device is self powered) – Does not affect panel standby batteries
Any number of wireless VADs can be added subject to address availability – Loop modules/Interface units can be used on wired loops where addresses are available but loop power low
White LED only- red drastically reduces light output
No costly loop card and additional cabling required to provide power to drive devices
No additional PSU’s required
Existing visual indicators can be replaced dynamically with compliant VADs in minutes
Max 126 wireless devices per wireless
loop (can be any combination)
Max 126 devices per
wired loop but subject to loop power
capacity
Up to 5 Radio Loop Modules per wired
loop
Up to 4 loops per CIE
Up to 8 CIE’s per wireless network –
4,032 devices
Up to 64 CIE’s per wired network
Typical Hybrid Scheme
Existing
Fire Panel
Up to 126 wireless devices per wireless loop
I/O
I/O
Wireless
Fire
Panel
Review
EN54-23 came into force from December 2013
Risk assessment approach required to ascertain where these might be required
Wall or ceiling mounted seen as best solutions
Hard wired systems may need extensive modification to comply
Service & Maintenance – As per BS5839:1, Clause 45 & 46/IS:3218
More Help? – FIA & LPCB COP
Questions
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