Thank you for the opportunity to help you with your question!
is a fire alarm device designed to respond when
the convected thermal energy of fire increases the temperature of a
heat sensitive element. The thermal mass and conductivity of the element
regulate the rate flow of heat into the element.
these basically sense smoke and give a warning alarm when there may be a possible outbreak of fire
these are used to detect poisonous gases in the air which are harmful to the human body
all these may be used at residential and work places
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