When you are in the market to purchase a new fire alarm, it will become clear quite quickly that there are a great number of makes, models and types of fire alarm to choose from. But where do you start?
It is also very easy to become confused about the sort of fire alarm that would best suit your needs. When faced with a range of alarms from optical, ionisation and heat sensitive alarms, you may become even more exasperated and worried about making the right choice.
What are the main differences between fire alarm models?
On the whole, you have three main types of fire alarm to choose from. Each type of alarm has it’s own uses and positive points. Lets take a look at the differences to make it clear which one you should choose to meet your needs.
Optical alarms are designed to project an infrared beam between two points. When the beam is broken, the alarm will be triggered and an alarm will sound alerting the building occupants to an incident or emergency. They work in a similar way to how infrared alarms work in banks and art galleries where beams are broken by criminal activity – much like what you see in films and on TV shows.
How they can work for you is that the infrared beams can detect larger smoke particles travelling through the air, so if there is a smouldering fire close by, the alarm will be triggered by the smoke that is being generated.
Ionisation alarms work on a system that involve two small plates – one plate is charged positively, and the second plate is charged negatively. There is an alpha particle source that creates a constant current running between the two plates. Should smoke particles generated by a fire enter the chamber and disrupt the charge, the charge gets dropped and the alarm will sound.
Ionisation alarms are better at picking up smaller smoke particles than an optical alarm, so you may want to choose this alarm option to help you detect fires at a very early stage and hopefully giving you a chance to extinguish the fire before any serious damage is done.
Heat Sensing Alarms
Heat sensing alarms are set up to trigger once the temperature within the room reaches a certain level. This means should a fire break out that generates a lot of heat, but not much smoke, a heat alarm will be a very effective way to raise the alarm and help people escape the building.
Heat sensing alarms do not detect smoke in the atmosphere, so are not a good choice if you are considering replacing old smoke alarms for something different. Because heat alarms are triggered by a rise in temperature, then they are ideal to be placed together with smoke alarms to give you a comprehensive fire protection system from both smoke and flame.
Fires can act in very different ways, so depending on what is burning, you may get more smoke than flames, or vice versa. This is why it is sensible to have both smoke alarms and a fire alarm for your protection.