Fire Alarms:
 

 1  What is BS 5839?

 

BS 5839 is the British Standard that governs the fire detection and alarm systems for buildings. Most commonly cited is BS 5839-1:2017, which covers the design, installation, commissioning and maintenance of non-domestic buildings. 

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 2  How often should my fire alarm be serviced?

 

The British Standards (BS 5839) state that that your system shouldn't go longer than 6 months without being serviced by a competent individual. For larger or more complex sites it is advised that this be reduced to 3 months. 

 

 

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 3  What category/type of system should I have?
 

This is possibly the most common question we receive. As strange as it sounds, thats not up to us to decide - or any fire service provider for that matter. In some cases your building insurer may dictate what category of system they require you to have, but in most cases the most suitable category will be suggested by your risk assessor. Their conclusion will be the drawn based on a number of factors, including the number of people on site at any one time, the contents of the building, the building's use and its layout. With that being said, we're happy to help you in any way possible.  

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 4  What does the fire alarm 'category' mean?

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You will see this mentioned on our service certificates and within your risk assessment. The fire alarm category effectively denotes the amount of coverage your system provides throughout the building.
Beginning with 'M' (for manual - requiring an individual to manually raise the alarm) to L1 which is the most comprehensive coverage - a legal requirement of places such as care homes.
Further information and a visual representation on the categories and how they differ can be found by clicking the picture below. 
 

 

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 5  What's the differences between the system types?
 

There are a few different types of fire alarm systems on the market. 
Non-addressable/conventional - These systems are quite simple in nature and are often the ideal solution for small buildings, businesses, shared accommodation etc. Each zone is wired to purposefully cover a particular area of the building. This will be represented back at the panel (most commonly) by corresponding LED's.
Bi-wire/Two wire - Almost identical to the above, these systems negate the need to wire in separate dedicated sounder circuits, instead utilising the zone circuit alongside the detection. 
Addressable - Perfect for larger buildings, or those with a complex layout. Instead of the zone wiring directly covering a certain area of the building, all of the devices are attached to one or more loops that will in turn cover the necessary areas. Each device attached will possess its own individual 'address number', that once commissioned by the engineer will give detailed information as to what exact device has been triggered. 
Wireless - Similar to addressable systems with regards to pinpointing a particular device, wireless systems can be the perfect solution for sites where cable runs are not really an option. Such as listed buildings or sites that have little to no downtime and require a quick and un-intrusive install. While the product itself is more expensive than the aforementioned, the comparative labor costs for installation of a wireless system are exponentially less.

 

 

 

 6  What's a closed protocol system?

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A closed protocol system refers to certain addressable fire alarm panels, namely produced by ADT, Gent, Notifier and Protec. These particular manufactures either don't share the required configuration software to third party companies, or require them to pay for access to it. Unfortunately this can prove highly detrimental to the end user. Over the years I've heard no end of customers complain of certain companies under cutting other tenders to an install, provide their own system, then subsequently hold the customer to ransom with extortionate service costs in the knowledge that there will limited alternative options for them.   

 

 

 

 7  How often do detectors need to be replace?

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While all addressable systems and a few manufacturer's conventional ranges have the ability to inform of contamination, most conventional and bi-wire systems do not. As such, manufacturers suggest that devices should be swapped out after 10 years. However, detection installed in dirty atmospheres (such as roof voids, factories etc) may well require changing sooner. 

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 8  Why do the panel batteries need to be replaced every 4 years?

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In 1995 the regulations and legislation surrounding fire alarm systems changed quite significantly. With the main change being that systems lacking a battery back up were made illegal. As such these systems have to be able to maintain themselves on said battery back up for a minimum of 24 hours, in the event of a power failure. 
Now, anyone who has ever owned a laptop thats spent most of its life plugged in will know - batteries don't tend to hold up too well unless they're exercised. Due to this, the BS5839 states that fire alarms (and their associated ancillary devices) should have their back up batteries replace every 4 years.

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