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FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Technical Advice => Topic started by: GregC on December 16, 2008, 12:56:10 PM

Title: System lifespan
Post by: GregC on December 16, 2008, 12:56:10 PM
What is a reasonable length of time that a fire alarm system would be expected to work before it is considered to require replacing.

From my experience.

Wiring 30 years
Detectors 10 years
Batteries 4 years
Panels ?
MCP ?
Bells?
Sounders?

I have heard that 15 years is considered for budgeting purposes for panels etc but am interested to see what you guys think.
Title: Re: System lifespan
Post by: Wiz on December 16, 2008, 02:33:31 PM
Much depends on the environment it is used in and how it has been used.

Therefore a 'Delapidation Assessment' should be carried out on a regular basis by a competent person*

* Source: Isle of Dwebble Electronic Safety Systems Emergency Planning and Review Quango report - 2007
Title: Re: System lifespan
Post by: John Dragon on December 16, 2008, 03:45:40 PM
Why 10 years on detectors?
Title: Re: System lifespan
Post by: Allen Higginson on December 16, 2008, 04:04:31 PM
Why 10 years on detectors?
I'm going to use the "R" word here - detectors should be replaced after 10 years as per manufacturers recommendations.
Here's Apollos (note CO detectors have a maximum life of 7 years) - http://www.apollo-fire.co.uk/editpics/207-1.pdf

Allen
Title: Re: System lifespan
Post by: Graeme on December 16, 2008, 06:31:53 PM
What is a reasonable length of time that a fire alarm system would be expected to work before it is considered to require replacing.

From my experience.

Wiring 30 years         agree but running elv could last for more
Detectors 10 years    agree and as per manufacturer
Batteries 4 years       as per BS
Panels ?                   as per their condition externally/internally during maintenances
MCP ?                      as per maintenance unless if K** as i really see problems with them in years to come
Bells?                       10 years and hopefully see the industry rid of them
Sounders?                 good point and should this mean that systems should have a full dBA test very i.e 10 years

I have heard that 15 years is considered for budgeting purposes for panels etc but am interested to see what you guys think.
Title: Re: System lifespan
Post by: Big_Fella on December 17, 2008, 08:25:34 AM
10 years always used to be the 'norm' as the majority of detectors were ionisation and the radio active element started to deplete at 10 years.  I think you'll need to seek advice from the particular manufacturer, they all vary, and it looks far more professional to your client if you say the manufacturers life span of the equipment is..... x years.

Also the life span given by the manufacturer would also be based on proper maintenance of the system/devices through its entire life.  The customer cannot expect a system to last it's 'duration' if for many years its not properly maintained.
Title: Re: System lifespan
Post by: Graeme on December 17, 2008, 11:53:07 AM
Big fella

customers expect everything to last forever
Title: Re: System lifespan
Post by: kurnal on December 17, 2008, 11:59:22 AM
I wonder if the 10 year life of a detector really was linked to the depletion of the radioactive source? With a half life of 432 years, this would be quite some margin of safety :)

I am grateful to wiki for the following information on americium 241.

Americium can be produced in kilogram amounts and has some uses, mostly involving 241Am since it is easiest to produce relatively pure samples of this isotope. Americium is the only synthetic element to have found its way into the household, where one common type of smoke detector contains a tiny amount (about 0.2 microgram) of 241Am as a source of ionizing radiation.

This amount emits about 1 microcurie of nuclear radiation when new, with the amount declining slowly as the americium decays into neptunium, a different transuranic element, with a much longer half-life (about 2.14 million years). With its half-life of 432 years, the americium-241 in a smoke detector includes about 5% neptunium after 22 years, and about 10% after 43 years.

After the 432-year americium-241 half-life, a smoke detector's original americium would, by definition, be more than half neptunium.

Title: Re: System lifespan
Post by: Thomas Brookes on December 17, 2008, 12:48:21 PM
Kurnal,

You have not swapped places with Benz have you, thats the sort of answer Benz would give!!
Title: Re: System lifespan
Post by: Big_Fella on December 17, 2008, 02:03:34 PM
Crickey.... my brain is hurting after reading that...

I'll send that to my customers to baffle them with that one.... Im sure Benz will comment on that  ;D
Title: Re: System lifespan
Post by: Wiz on December 17, 2008, 08:07:24 PM
Prof. Get a life! (half?) :)
Title: Re: System lifespan
Post by: Galeon on December 18, 2008, 05:37:06 PM
If all is well , this equipment on 24/7 365 days a year , so do the maths (no no no dont do the maths) over 10 years it aint done bad .
Title: Re: System lifespan
Post by: Allen Higginson on December 19, 2008, 12:17:21 AM
How many of those who moan about replacing their detection equipment have home entertainment systems (TV's,Video Player/Recorders,audio equipment) in excess of five year old,never mind ten!!!
Title: Re: System lifespan
Post by: Big_Fella on December 19, 2008, 08:39:26 AM
It always comes back to the old saying, the fire alarm is a begrudging purchase. 

Now if the fire alarm panel had a small TV screen in it for the receptionist to watch them I'm sure it would be a different ball game altogether  ;D
Title: Re: System lifespan
Post by: Galeon on December 19, 2008, 08:47:07 AM
I told you to keep quiet about our meeting with the Dragon's
Title: Re: System lifespan
Post by: Big_Fella on December 19, 2008, 08:49:42 AM
ha ha ha, I am sure this will trigger Benz thought patterns
Title: Re: System lifespan
Post by: Thomas Brookes on December 19, 2008, 12:46:47 PM
May be if there was a golf game in it some where, Directors might want one fitting in each room
Title: Re: System lifespan
Post by: Fishy on December 22, 2008, 08:29:48 AM
CIBSE gives some guidance on this.  Their "Guide to ownership, operation and maintenance of building services" quotes 10 to 15 years for smoke detectors; 20 to 25 years for the fire alarm systems themselves.