Lee James, General Manager at the fire detection product manufacturer Nittan Europe, looks at the impact of e-cigarette use on fire detectors and latest recommendations on avoiding false alarms caused by vaping.
The Health Act 2006 prohibited smoking in enclosed public places and workplaces, on public transport and in vehicles used for work, justified on conclusive scientific evidence that smokers put others around them at risk by exposing them to second-hand smoke. It’s doubtful anyone could have predicted one of the side effects of this monumental change to our laws: the incredible growth of the e-cigarette market. E-cigarettes have been one of the fastest growing industries in the world. Invented in 2003, the modern e-cigarette is a newcomer but from 2007 onwards, post smoking ban, the e-cigarette / vaping industry started to truly emerge in the UK.
Now, the UK is the third biggest vape market in the world, behind the USA and Japan. According to latest statistics released from the government this July, 3.2 million people use e-cigarettes – 6.3 per cent of the population of Great Britain (up from 3.7pc in 2014). The figure is considerably higher for current smokers (up to 15pc) and for ex-smokers; 35 to 49-year-olds are the largest user group, with men in the majority.
Whilst e-cigarettes are a popular and effective means of quitting smoking and are 95pc safer than smoking, they do bring with them safety issues that no one was expecting: false alarms from fire detectors.
How does vaping trigger false fire alarms?
E-cigarettes feature a cartridge containing nicotine in a solution of either propylene glycol or glycerin and water. When you suck on the device as you would a normal cigarette, a sensor detects the air flow and starts a process to heat the liquid inside the cartridge so that it evaporates to form a considerable amount of water vapour. When a group of people vape at the same time indoors, the resulting water vapour can have the same effect as steam on smoke detectors, especially optical ones, resulting in a false alarm.
To explain the mechanics behind this issue, a false alarm – that is, an alarm which has been generated by the fire detection system but not in response to an actual fire – is caused by the Infra Red scattered light technology in the detector being unable to distinguish between smoke and larger size particles like steam and dust. Although vaping produces water vapour (tiny droplets of water), not steam (water in a gaseous state), the reaction from a traditional single optical sensor detector is often the same, due to the similarity in size of both the particles.
As we are all well aware, false alarms are one of the biggest issues faced by the fire industry and cost the UK in excess of £1 billion per annum. False alarms not only cause disruption for ongoing business activities, but also result in financial loss as the business has to deal with the alarm. Moreover, they taint customer experiences which may have a negative effect on businesses in the long run. Hence, minimising the number of false alarms is a key priority for all concerned. Whilst a business must always comply with fire detection and alarm systems requirements, no one should have to put up with the constant nuisance of false alarms.
Ban indoors?
The Health Act 2006 does not cover vaping and organisations are free to make their own policies on the use of e-cigarettes on their premises. Workplace environments vary greatly and there is no one-size-fits-all approach. What’s more, different organisations within the same sector frequently have completely different policies, especially so in the leisure industry. Pub chain Wetherspoons, for example has a complete ban, whereas many leaseholder pubs permit vaping indoors.
Businesses in the leisure sector, including bars, music venues and hotels, are particularly problematic as the customer demographic is more aligned with the main e-cigarette user age group (25 to 49-year-olds), plus prior to the ban, these places were heavily associated with smoking.
Leisure venues are understandably more reluctant to ban vaping indoors as it may negatively impact on the quality of experience that is offered to their patrons and there has even been talk about it having a correlation to the large number of pub closures over the past few years (although this is a complex issue).
Multi-Sensors: solution or compromise?
The Fire Industry Association (FIA) Fact File 85 puts multi-sensor detectors forward as a more resilient alternative to standard optical detectors.
The 2018 Building Research Establishment (BRE) Briefing Paper, ‘The performance of multi-sensors in fire and false alarm tests’, backs up the use of optical heat multi-sensor detectors in preventing false alarms. The paper reports on the testing of the full range of optical heat multi-sensor detectors available in the marketplace at that time – 35 in total – and estimates that potentially 38.1% of observed false alarms could have been reduced if multi-sensors had been present. However, a false alarm test covering synthetic smoke was not possible due to difficulties with developing a repeatable test.
What’s more, the BRE research demonstrated that, although delayed, in all cases alarms were given from non-combustion materials. The delay might allow for any transient false alarm sources to disappear before the fire threshold is reached, but it does not entirely stop a false alarm in these instances. Furthermore, to ensure this delay, some Multi-Sensor detectors have been configured (or can be configured by the installer) to be less sensitive which is a compromise that is not always acceptable or ideal.
Alternative: dual optical detectors
In addition to multi-sensors, FIA Fact File 85 also puts forward dual-wavelength or dual-scatter optical smoke detectors as a suitable alternative.
Dual optical detectors use both the ‘traditional’ Infra-Red light used in a single optical detector, plus blue LED light technology, to ‘view’ particles entering the alarm chamber. By calculating the ratio of these light sources, which operate at different wavelengths, the detector can determine the particle size and thus easily distinguish between smoke and non-combustion products. As steam and dust are much larger particles than smoke, the detector won’t trigger a false alarm but will still remain sensitive to combustion products in order to generate an alarm.
This technology, which has been employed in Nittan’s Evolution EV-DP smoke detector, pictured, is proven in the field. At Southampton’s small but legendary pub and music venue, The Frog & Frigate, customer vaping was leading to regular false alarms, causing disruption. Venue owner Derek Gardener comments: “we have a relaxed, fun vibe here and are happy for people to use e-cigarettes inside. However, it has led to the alarms activating, especially when people are vaping right underneath them. We can’t stop people from vaping underneath them and equally we didn’t want to ban vaping.” Derek’s fire alarm service provider, Fire & Safety Testing Ltd of Southampton, replaced the detectors with dual optical ones and, six months later, not a single false alarm had been reported.
Nittan has now taken this technology a step further, by incorporating dual optical technology into a multi-sensor with a heat sensor. The EV-DPH multi-sensor has the ability to reduce false alarms caused by vaping and other non-combustion sources, without the need to lower the devices’ sensitivity to actual combustion products. The technology has been further developed to make the detector more sensitive to flaming fires by shifting the alarm threshold level when the ratio of the two scattered light wavelengths indicate that the particle size present is similar to the smallest size defined as a smoke particle.
Conclusion
A study published in the British Journal of General Practice says that switching to vaping could save as many as 6,000 lives per million smokers every year. Public Health England recognises this and aims to secure a tobacco-free generation by 2025. It believes e-cigarettes could be contributing to at least 20,000 successful quits of smoking every year. So, e-cigarettes and vaping are certain to remain popular for, at the very least, the next decade.
Many organisations have banned vaping indoors, but those that permit it need an effective method of preventing it leading to false alarms. Standard multi-sensors were the go-to solution, but evidence is increasingly mounting against them when it comes to vaping. If you have a customer where vaping is permitted then pause for thought and consider switching to dual optical alarms; modern times call for modern solutions.
