L1 or L3 design question

[ElecTech]

Quick design conundrum...

 

We have had a tender through to quote a L3 system in a 100mx100m warehouse with internal offices at the front (the standard type of warehouses nowadays, sheds with an office). 

 

The way I interpret L3 is that all escape routes must be covered etc., my question is - would the bulk warehouse be classed as an escape route? I'm presuming so, if so the L3 is very close to an L1 except a cleaner cupboard or two, but even in a cleaner cupboard scenario, the argument is there to be had that EVERY room is an escape route if it has a potential of having people in at any one time? 

 

Someone must know more on this than me & there must be a explanation, I cant get my head around that every room or corridor will be an escape route in any building or has the potential to be...? I don't see a huge difference at all between L1 & L3?

 

Cheers,

[james.wilson]

Imo easy way, if it's got an external door or fire door or change of level its an escape route. Also any corridor or area with areas of it

[Shaunb1905]

As above 

 

A lot of the time I find L3s can be very similar to L1 depending on the layout so I just go L1 anyways 

Edited September 5, 2018 by Shaunb1905

[Amps]

[al-yeti]

23 minutes ago, Amps said:

Why have the two cp in those locations the two away from exits? 

[Amps]

7 hours ago, al-yeti said:

Why have the two cp in those locations the two away from exits? 

 

Dont ask me I wasn’t involved in the design stage 

 

 

[Shaunb1905]

Travel distance doesn't seem to be more then 45m or reduced to 25 for special hazards?  

[Amps]

Could be any of these  

 

[james.wilson]

as above id say search distance 

[sparky999]

5.1.3 Category L systems
Category L systems are automatic fire detection and fire alarm systems intended for the protection of life. They are
further subdivided into:
a) Category L1: systems installed throughout all areas of the building.
The objective of a Category L1 system is to offer the earliest possible warning of fire, so as to achieve the
longest available time for escape;
b) Category L2: systems installed only in defined parts of the building.
A Category L2 system ought to include the coverage necessary to satisfy the recommendations of this standard
for a Category L3 system; the objective of a Category L2 system is identical to that of a Category L3 system,
with the additional objective of affording early warning of fire in specified areas of high fire hazard level and/
or high fire risk;
c) Category L3: systems designed to give a warning of fire at an early enough stage to enable all occupants, other
than possibly those in the room of fire origin, to escape safely, before the escape routes are impassable owing
to the presence of fire, smoke or toxic gases;
NOTE 1 To achieve the above objective it is normally necessary to install detectors in rooms which open onto
an escape route (see 8.2).
d) Category L4: systems installed within those parts of the escape routes comprising circulation areas and
circulation spaces, such as corridors and stairways