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Can false alarms ever be stamped out?

02 January 2013

If a system has too many false alarms it is not compliant. That was the message from a recent gathering of senior figures in the fire safety industry.

Brought together by telecare, life safety, communications and security systems provider Cirrus, they spoke in front of a select audience of housing associations, local authorities and facilities and property management organisations. On the panel at the grand Vinters’ Hall in the City of London were Cirrus’ Commercial and Technical Manager Roy Wilson, Apollo’s EMEA Business Innovation Manager Paul Pope and London Fire Brigade City of London Station Manager Steve Norman.

When it came to false alarms, all three agreed the purpose of an alarm system is to alert people to a fire at an early enough stage to evacuate safely. If a building’s users become complacent because of multiple false alarms (such as halls of residences, filled with students burning toast) the fire safety arrangements at the premises could be undermined.

“In reality,” said Paul Pope, “a manufacturer can set fire detectors sensitivity for a specific set of conditions and it may never produce a false alarm. However, it may also not detect real fires or be certificated to the relevant standards either and this should be its priority.”

Steve Norman then explained the difference between a false alarm and an unwanted fire signal (UwFS). “A false alarm is an actuation that was not due to a fire, whereas an UwFS occurs when a false alarm is passed to the Fire & Rescue Service (FRS) as a call to attend,” he explained. Defining them and analysing the causes correctly is a crucial part of managing life-saving resources.

As well as false alarms and UwFS and their impact – both on the organisations producing false alarms and the FRS– the panel covered detector types, compliance, maintenance, and responsibility for systems.

They also asked the audience to always remember why fire detection and alarm systems, risk assessments and emergency plans should go hand in hand.

“A suitable and sufficient fire risk assessment will reduce the risks associated with a fire by identifying the correct detection and alarm system and emergency plan required.”

Afire detection and alarm system is primarily there to alert people of the possible danger of fire and for the premises management to implement the emergency plan,” said Steve Norman. “A suitable and tested emergency plan will ensure risk of death and injury from fire is minimised and property damage is reduced.

Below are the topics covered in more detail…

Sticking to the rules

Complying with legislation means choosing the appropriate fire safety equipment and maintaining it correctly, says Roy Wilson.

“The majority of British Standards are not mandatory, but following them means you are following best practice and are most likely to be a long way towards complying with the Regulatory Reform (fire safety) Order (RRO), which IS mandatory.”

To identify the right equipment, a building needs to be classified. The relevant FSRA guide will cover different building classifications and applications – crucial in identifying best practice. The FSRA guides are Government publications to support people in complying with the RRO and within which the British Standards are referenced.

The FSRA guidelines are written to allow people who know the building to manage it with a minimum of bureaucracy. It is the duty of the person responsible for the building to tell the assessor how the building works and how its residents use it.

“People’s behaviour is the single most important factor in fire risk assessment. Only once all these things are known can an accurate risk assessment be made,” adds Roy.

The Local Government Group – a collection of organisations who act as a national voice for local authorities – has also published more detailed guides. However, the wealth of guidelines doesn’t necessarily mean extra expenditure for building owners – sometimes it means exactly the opposite.

Cirrus engineers have been able to tell landlords that not only do they not have to upgrade their fire alarm systems, but in some cases to be compliant they should remove them altogether. In one example quoted by Roy Wilson, Cirrus found a building’s use and construction and changes to regulations meant it didn’t need the existing fire system so there was no need to replace it. Changes like this enable the owners to save a fortune on capital expenditure, management and maintenance.

Categorising a building

A fire risk assessment is a working document that will evolve as the building’s use and residents change. So regular review of how a block will be used and then categorising it accordingly is key as it will dictate what types of equipment need to be used – and where.

This is particularly relevant in residential blocks. Flats can be converted from general use into sheltered accommodation – and vice versa – which will dramatically change their fire safety requirements. A recently-built block being used for general residential purposes may not need fire detection in communal areas such as corridors as residents are deemed able-bodied enough to evacuate. If the block was being used for sheltered accommodation however, it would require detection. It would also need someone to manage the system and possibly to co-ordinate evacuations.

Size is a key factor in defining a block’s needs. RRO requirements demands “emergency routes and exits requiring illumination must be provided with emergency lighting of adequate intensity in the case of failure of their normal lighting.”

Age is key too. Buildings constructed under the 2000 building regulations should inherently be constructed with appropriate and adequate fire safety measures. Older developments may require additional or supplementary precautions to supplement older building construction methods, although newer building will still need to be assessed to check they haven’t been modified in ways that affect fire stops, risers and bathroom ducts.

All this makes it very important that buildings are classified correctly and the right systems are chosen to reflect this. Ultimately, this is the responsibility of the person responsible for the building – the landlord or freeholder – with their fire risk assessor.

Running smoothly

The RRO obliges the person responsible for the building to make sure equipment is “maintained in an efficient state and in efficient working order”.

Systems like Emergency lighting and smoke ventilation will be rarely used, but may fail if they are not correctly maintained. The chances are they will do so when they are most needed too. At the very least, they will cause faults and false alarms, all of which will end up costing more than a regular maintenance programme.

When it comes to shelf life, manufacturer recommendations are a good starting point. The majority of detectors have a 10-year lifecycle and though they may well last longer with careful maintenance, their replacement should be in an action plan geared around a date close to the end of their recommended life.

There are no mandatory requirements that apply to the engineers, who will carry out maintenance, but the legislation requires them to be “competent”, and this means they have sufficient training and experience or knowledge to do the work.

Picking the right detectors

The technology to reduce false alarms is secondary to the technology that detects fires. That means picking the right type of detection to suit the fire risk rather than the best to avoid false alarms is critical. These can include point-type smoke, heat and CO fire detectors, IR and UV flame detectors, beam smoke detectors, linear heat cables and sealed heat detectors.

So how do you pick the right detection products? Smoke is a reliable and early indication of fire, heat is reliable but in many cases will not detect the early stages of a fire. Gas detection is not yet ready for general purpose IR and UV light are useful in special circumstances

Any assessment first needs to work out the risk of a fire developing in a certain area. If a risk is identified, is it likely to be a rapidly-developing, high-energy fire or a slow developing smouldering type?

If an ionisation smoke detector has a good response to flaming fires and an optical smoke detector responds well to visible smoke particles. Carbon monoxide multi-sensors (CO and heat) fire detectors are also good for smouldering fires in rooms up to 50 square metres with some benefit in detection if variations in ceiling heights have led to a “layering” of the smoke. Smoke detectors should always be used as the primary detector in escape corridors.

What about dirt, dust or moisture? In these situations a heat detector might be more appropriate and may cause fewer false alarms than a smoke detector – but not if there are likely to be significant variations in temperature or life safety protection/early detection is required as part of the fire risk.

Multi-sensor detectors can often be the most effective all-round detector as it often uses a combination of optical and heat detection.

False alarms – the impact

False alarms and UwFS disrupt business, erode confidence in the system, divert essential services from emergencies and are ultimately a drain on resources. The London Fire Brigade (LFB) policy outlines that false alarms may contribute to fire safety issues such as complacency or highlight poor fire safety management and UwFS impact heavily on FRS resources.

In the past, explains Steve Norman, most false alarm and UwFS policies have focused on ‘high repeat call’ premises.

In particular, the spotlight has been on a relatively small number of premises generating a large number of false alarms and UwFS.

But as it became apparent a large proportion of the total false alarms in London came from buildings producing just one or two false alarms per year – and these are not, generally, poorly performing fire detection and fire alarm systems – the FRS realised stopping the ‘ones and twos’ is as important as the ‘repeat offenders’.

From an organisation’s point of view, false alarms are costly. Steve Norman cites a London hospital that was recording more than 250 false alarms per year. Analysis of the cost of three different evacuation scenarios ranged from £230 to over £655. Or, as he puts it, “a lot of money for a burnt piece of toast or a poorly sited manual call point”.

But in the age of austerity, when a business is looking at driving down costs this starts to become an important factor – especially if they are buying new alarm systems.

British Standard 5839 Part 1 has guidelines which balance the number of false alarms against the number of system detectors but people must remember this is different to UwFS. The LFB policy points out that any UwFS is unacceptable..

Steve Norman is quick to point out this is not an acceptable rate of false alarms. “You can have false alarms where the sensitivity of a system is required for your risk, but you need to manage it,” he explains. “A hotel may decide smoke detection in rooms is the best way to protect guests, but the management has to accept this is likely to lead to more false alarms and should manage the system so it doesn’t automatically send a call (UwFS) to the FRS.”

False alarms – the solutions

BS5839-1 states that the effective system performance of an alarm system is down to correct design, installation, commissioning, acceptance and maintenance. If these are all in place, false alarms are “unlikely to occur”.

Algorithms play a key part in this by helping the detector ignore transient environmental conditions while ensuring its detection capability is not significantly affected. They can be adjusted to react to different environments, but all the response modes must be certificated to the relevant product standards.

But understanding the difference between a false alarm and an UwFS is also “fundamental” to applying the correct resolution process, stressed Steve Norman. False alarms require an investigation of cause and introduction of improved control measures. UwFS require a consideration of filtering practices to prevent unnecessary demands on emergency services.

While the large number of primary fires in London are good reason to keep attending AFAs, only a tiny proportion of these fires left their compartment of origin, revealed Norman. Many were extinguished before the FRS arrived or extinguished by firemen using an extinguisher.

“Is there a life risk?” asked Steve Norman. “Yes but if the fire safety arrangements are working and managed properly then the risk is substantially reduced.

Systems up to the job?

Who is responsible for what? Manufacturers are responsible for factory production control while it is the certification body’s job to test the product and assess the factory. All of this should show products meet appropriate standards. The EU Construction Products Directive soon to be the EU Construction Products Regulation is embodied within the UK building regulations.

Products should be able to withstand real life conditions but Paul Pope said that certification is a minimum, not a maximum. “Fire detection products should be designed to be transported worldwide, withstand harsh conditions associated with the installation process and in environments they are protecting,” he explained. “After all that they are expected to work perfectly for 10 years – performing around 300 million operations in the process – whether they are installed in hot/humid or cold/damp climates.

“They are also expected to work within congested EMC environments (with mobile phones, radios and MRI scanners and RF transmitters)and around insects. And they also need to cope with long cable lengths and interference.”

System reliability needs:

? Environmental performance
? Dust rejection
? Insect resistance
? fail-safe algorithms
? Robust comms protocol
? Drift compensation
? Reliable manufacturing
? Correct sensor selection

Reducing false alarms without losing response to real fires is the real challenge. Only by assessing conditions and then putting the correct detectors in the best positions can you ensure they detect fires with a minimum of false alarms.

Who is responsible for reducing false alarms and UwFS?

The people who have a role in managing fire alarm systems and reducing false alarms and UwFS are:

? Responsible person (RP)
? Alarm installer
? Service providers and maintainers
? Fire alarm monitoring organisation (FAMO)
? Insurance company
? FRS (Control/Fire Safety IOs/Ops crew)
? Industry stakeholders (3rd party acc., FIA, etc.)

In most situations, says Steve Norman, the various aspects of fire alarm management are not sitting against the right group with control for that issue, or effective co-operation is not taking place.

“Some maintainers carry out regular maintenance without discussing with the RP why false alarms have occurred and if they don’t do that, they cannot put effective control measures in place to reduce false alarms,” he adds.

Minimising false alarms should be part of the contract (it is part of BS5839, after all), and companies with too many false alarms could well be paying for a maintenance service they are not receiving.

A FAMO can’t unilaterally determine how to deal with an AFA signal. That is the job of the RP, who will dictate how activation is responded to in line with the emergency plan drawn up as part of the Fire Risk Assessment and Emergency Plan.

What an FAMO can influence and introduce are important support measures. For a start, it can make sure the correct people have input at the right stages in the alarm system management process.

There is no single solution to the problem though. It requires a delicate balancing of cultural changes in risk perception and industry partnerships, concludes Steve Norman.

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