摘要 |
<p>A heat sensitive air/gas sampling device including an apertured housing for connection to a pipe leading to a smoke detector device the housing including a blocking device for preventing air/gas to enter the housing, the blocking device being ineffective to prevent ingress of air/gas when the surrounding temperature exceeds a predetermined maximum for a predetermined period of time. The blocking device may be held by, or composed of, a low melting point wax. The blocking device may be comprised of a bimetallic strip.</p> |