SENSE OF DIRECTION

摘要

Until quite recently, the top priority in designing a new fire detector was to make it sufficiently sensitive to detect potential fire situations fast enough to raise an alarm before a serious fire developed. However, with modern technology now available, sensitivity is rarely, if ever, an issue, even with the simplest of detectors. What has become much more of a concern is the ability of detectors to discriminate between false alarm situations - for example, a false activation resulting from steam or tobacco smoke - and those situations that genuinely indicate that a fire has started.rnThe importance of this issue is emphasised by the Chief Fire Officers' Association policy (first introduced in September 2004 and currently being updated) on fire service response to false alarms. Fire services in the UK now identify and monitor the performance of fire alarm systems, and the policy can result in a significantly downgraded response from brigades to alarms generated by automatic installations that have a poor false alarm record.