Smoke alarms withstand cold (5.9.2006)

05/09/2006

The cold-resistance of battery-operated smoke alarms and carbon monoxide alarms was investigated in one of our projects. We purchased five different alarm models from the market and had them tested for cold resistance by VTT.

The tests showed that various battery-operated alarms do not very easily react to the temperature of –10 °C, neither to air temperature fluctuating between 0 °C and –10 °C. In most alarms, however, the terminal voltage dropped clearly during the test. No product showed extra alarms, and they reacted normally to smoke and/or carbon monoxide after the three-week test. The noise level also remained adequate after the test.

When the alarm is used at a summer cottage, the voltage of new batteries may drop under the warning limit already in one month. Therefore, the user has every cause to test the smoke alarm after a longer absence, and otherwise with one-month intervals.

Most instructions for use tell that smoke alarms are not suitable for damp facilities, such as bathrooms, and not even near to them. Also, battery-operated smoke alarms are not suitable for any outdoor use whatsoever, as the air humidity may damage the device already in three weeks.

The average maximal lifetime of a smoke alarm is 10 years. For some models, the operating life told by the manufacture is 7—10 years. Towards the end of the working life, the smoke alarm typically becomes excessively sensitive e.g. to dust, and gives extra alarms before turning inoperative.

For more information:
Risto Raitio, tel 010 6052 446

 

The Finnish Safety and Chemicals Agency (Tukes) endorses the safety and reliability of products, services and industrial activities. Our goal is a trustworthy, safe and competitive Finland.

 

We want to be a provider of protection – to improve and facilitate safe practices across the society.