It goes without saying that fire is deadly. Whether it occurs in a natural or man-made setting, a fire that is allowed to spread out of control can injure, killed, and cause devastating property damage. Mitigating the risks of fire is the driving force behind fire alarms. We install fire alarms in residential and commercial structures so as to alert occupants that a fire has started. The faster the occupants are alerted, the more quickly they can take action.
From a scientific standpoint, fire alarms are fairly simple devices. But the psychological impact they have on the occupants of burning structures is profound. As such, fire alarms are purposely designed to demand attention once they go off. You know yourself how difficult it is to ignore a sounding fire alarm.
The Need is Real
A quick perusal of Seton fire alarms information clearly demonstrates the need for working fire alarms in all commercial buildings in the UK. You can find similar information in just about every country in the world. Why? Because the need is real. Fire alarms are not just extra accessories that make buildings a bit nicer to own.
A comprehensive study published in January 2019 shows just how real the need for fire alarms is. That study cited, among other data, numbers from the World Health Organisation (WHO) showing in excess of 300,000 annual deaths caused by fire induced burns. The numbers say nothing of smoke inhalation.
The study also cites data that shows that structure fires are consistently a major threat to building occupants and that said fires are usually caused by human behaviour. That is pretty sobering.
Scientific study shows that people are more likely than not to be the cause of structure fires. Whether through carelessness, ignorance, or a combination of both, we human beings have a bad habit of setting fire to those structures we live and work in. Moreover, we seem to be doing it with greater frequency.
Get Up and Get Out
Getting back to the science of saving lives with fire alarms, it is all about warning people to get up and get out when a fire is present. This can be accomplished in different ways. In terms of warning occupants of a fire, there are both audible and visual warnings to consider.
Fire alarms make a tremendous amount of noise for obvious reasons. But it goes further than merely alerting occupants. The noise emitted by your typical fire alarm is intended to be both ear piercing and annoying. Fire alarms are not supposed to emit pleasant sounds that make you feel comfortable. They are annoying specifically for the purpose of encouraging occupants to flee a burning building.
There are times when annoying alarm sounds are useless. For example, audible alarms do not help the hearing impaired. As such, fire alarms also present intense strobe lights intended to do the same thing. Again, these are not warm lights that are pleasant to look at. They are bright strobe lights that actually create a visual annoyance. They are based on the scientific principle that people will attempt to get away from things that annoy them.
Detecting Fire and Smoke
Another aspect of the science behind fire alarms is how they actually detect fire and smoke. Again, there are several options. The most basic of all fire alarms monitor for smoke by way of a photoelectric sensor. The sensor both emits light and measures its return. If smoke passes between the two ends of the sensor, it triggers an alarm.
Smoke can also be detected with ionization alarms that rely on a small amount of radioactive material capable of monitoring the air by way of a constant electrical current. Smoke can interrupt that current, thus setting off the alarm.
Another method of detecting fire is with a device equipped with heat sensors. These types of fire alarms are actually older than smoke alarms. They rely on a certain amount of heat to trigger an alarm when it reaches a given temperature. Unfortunately, heat detectors are not as effective as smoke detectors.
All monitors for smoke and/or heat have one thing in common: they rely on slight changes in the environment to do what they do. As such, they are subject to false alarms. That is why today's modern fire alarms are so finely tuned. Designers want them to be as accurate as possible with the lowest risk of a false alarm.
The science of saving lives with fire alarms involves both human and mechanical components. The human component is all about providing a warning that is annoying enough to demand attention and tell people to get up and get out. The mechanical component is all about designing smoke and heat devices capable of detecting fire in its earliest stages. Both lives and property are saved when the two work to their fullest potential.
