Detection alarms

Operator shuts down operation in response to vapor detection alarm... 

Consider the need for gas detection/alarms, e.g. for hazardous gases left in use out of normal hours. 

Check for leaks with soapy water and consider the need for automatic detection/alarms. 

Installation of detection, alarm and sprinkler (or other suppression) systems ... 

It is essential to discuss the requirements for stmc-tural protection, compartmentalization, emergency lighting, detection, alarms, call points, suppression, means of escape and signage with the applicable local authority, fire brigade or insurance company personnel before finalizing designs. 

Check for leaks (e.g. with aqueous ammonia) and consider the need for detection/ alarm systems. Leaks should be dealt with immediately after evacuating the area. 

A combination of detectors may be appropriate. They may activate an alarm only, or actuate a combined alarm/extinguishment system. With a bank of detectors a voting system may be used to increase reliability and reduce the frequency of spurious alarms. Detection/alarm systems may also be interlinked with, e.g., fire-check doors held back on electromagnetic catches such that the doors close automatically upon activation of the detection system. 

Consider the need for detection/alarm systems and in any event check periodically for leaks with e.g. soap solution, never with a naked flame. 

In general practice, the gas detection alarm set points are the settings recommended by the manufacturer of the equipment or by requirements of an operating company to effect an acceptable compromise on any given field of operation. The lower the set points the higher the sensitivity to possible leakage emissions. 

Installing detection alarms to alert staff to levels that approach the threshold limit value (TLV), permissible exposure level (PEL), or other predefined concentration of the material. 

Verifying operation of detection, alarm bells, and notification... 

All electrical systems, including detection, alarms, supervisory systems, and manual activation systems, should be function tested to ensure proper operation. 

About the size of a package of cigarettes, individual sensors are available for H2S, phosgene, N02, HCN, and CO. In the near future, the series will be expanded to include CI2 and hydrazine. When used with the Chronotox microprocessor, the Monitox serves as a personal monitor as well as a gas detection alarm system. 

Automatic Chemical Agent Detection Alarm (ACADA-M22). The M22 is an advanced, pointsampling, chemical agent alarm system employing ion mobility spectrometry. It is designed to detect standard nerve and vesicant agents. 

Fire and explosion protection system drawings or arrangements (fire gas detection/alarm, protection - passive and active). ... 

The time lag between sampling and the availability of the analytical result, in case of a detected alarming concentration, usually does not allow timely action to prevent further harm. 

Fire detection, alarm, control and suppression systems. 

As the steam generator was being operated iso thermally at 700 °F. without water when the flow stoppage occurred, the steam-to-mercury barrier must have failed initially without detection, during previous steaming operations. This leak would then have allowed steam to condense in the mercury system and form an undetected water layer in the mercury-system expansion tank. The initial failure was probably not detected because of a fault in the leak-detection alarm system. The subsequent leak in the sodium-mercury barrier then allowed the water collected in the mercury system to enter the sodium. 

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