Emergency lighting duration

[BillyH]

What would be the minimum emergency light duration for commercial premises comprising of 2 storey offices approximately 150 sq metres per floor? Occupancy is currently 15 personnel but may rise in the future. Obviously we need to consider worst case scenario but, cannot see for the life of me why 3 hour duration would be required. I would imagine the building to be evacuated in less than a minute. What else needs to be considered?

 

[GLENNSPARK]

3 hours

 

[worzol99]

3 Hour is the minimum

 

[BillyH]

Ok, you say 3 hours. Is 3 hours always the case when emergency lighting is required?

 

[worzol99]

Usual test is 3 hours long

 

[KAS1]

I think 3 hours is required due to all the cut backs, in some areas the firemen arrive on old trade bikes with a bucket of sand instead of a fire engine and it can take up to 3 hours to arrive.

 

[Guest55]

Ok, you say 3 hours. Is 3 hours always the case when emergency lighting is required?

no , certain non residential buildings require only 1 hour duration but most self contained luminaires have 3hr battery packs as standard.

examples of 1 hr emerg lighting types include schools , colleges , town halls , office buildings , libraries , shops , warehouses and factories.*

*source - IET guide to em lighting.

 

[BillyH]

no , certain non residential buildings require only 1 hour duration but most self contained luminaires have 3hr battery packs as standard.

examples of 1 hr emerg lighting types include schools , colleges , town halls , office buildings , libraries , shops , warehouses and factories.*

*source - IET guide to em lighting.

Cheers biff, the reason I asked is the current em lights are showing signs of age and do not satisfy 3 hour duration. Client being tight so does'nt want to pay for new batteries etc

 

[Guest55]

Cheers biff, the reason I asked is the current em lights are showing signs of age and do not satisfy 3 hour duration. Client being tight so does'nt want to pay for new batteries etc

what type of building is it ?

 

[BillyH]

I think it used to be an industrial unit but now converted to 2floors of office space

 

[Guest55]

no worries then
but if theyre not lasting 3 hrs now it will only take 1 year or 2 before they fail 1 hr test.
just delaying the inevitable really.

 

[BillyH]

no worries then
but if theyre not lasting 3 hrs now it will only take 1 year or 2 before they fail 1 hr test.
just delaying the inevitable really.

yes, I know. Probably hoping better times or on their way

 

[robsparky1975]

BS5266 should clarify this,any fitting that are not up to the duration should be replaced/repaired to make them meet the criteria,recession or no recession the person who is liable for the building has a duty to keep it fit for use,including EM lighting,if you put down failures then so be it,if they decline and something occured would be them liable.

 

[BillyH]

BS5266 should clarify this,any fitting that are not up to the duration should be replaced/repaired to make them meet the criteria,recession or no recession the person who is liable for the building has a duty to keep it fit for use,including EM lighting,if you put down failures then so be it,if they decline and something occured would be them liable.

But if they only need 1 hour and are lasting 2 then, surely they comply

 

[tazz]

But if they only need 1 hour and are lasting 2 then, surely they comply

No when testing em lighting the duration is important to recyle the nicads, the old BS5266 had it right with 3 x 1 hours tests and 1 x 3 hour test per year, if the nicads are not fully disscharge once a year, them the old memory effect sarger comes in, and suddenly you find a em light giving 10 minutes duration.
Im sure most of you have come across this when your battery drills say fully charged and last 5 minutes