Fire alarm device

Simple switches that can be manually activated can be considered a fire alarm device. Models are used which normally require the use of positive force, i.e., to avoid accident and fraudulent trips. Fire alarm switches normally can only be reset by special tools in order to trace the source of the alarm, however sophisticated data reporting systems with addressable data collection may make this requirement obsolete. 

As mentioned above, smoking may have some advantages besides its inevitable negative feature since it provides an early indication of a fire hazard and enables the visual location of the seat of the fire. In fact, smoke is a feature which is utilized by some fire-alarm devices, either operating on optical principles or using an ionisation chamber for detecting the changes in electric conductivity of the atmosphere. 

A switch provided on a fire alarm system that is manually activated to indicate a fire event (see Figure M.2). The switch is configured to conspicuously identify it as a fire alarm device and is usually fitted with a tamper device (break glass, rod, or cover) to discourage or prevent false activation. It sends a signal to a central monitoring station for notification of location and activation of alarms. 

Polymeric Early-Warning Fire-Alarm Devices", NASA CR-134764. 

Automatically monitor and control fire detection and fire alarm devices and their power supply... 

Fire-detection devices such as flame-sensing or ioni2ation-interference types operate much more rapidly than sprinkler heads and are used extensively both as alarms and to activate fixed fire-extinguishing systems. 

This is a simple example for the capability of KAMINA to be used as a sensitive fire warning device. Unlike conventional devices for that purpose, which work on the basis of optical aerosol particle detection, the gas analytical KAMINA will not give false alarms caused by dust or soot particles. 

Heat detectors normally have a higher reliability factor than other types of fire detectors. This tends to lead to fewer false alarms. Overall they are slower to activate than other detecting devices. They should be considered for installation only where speed of activation is not considered critical or as a backup fire detection device to other fire detection devices. They have an advantage of suitability for outdoor applications but the disadvantage of not sensing smoke particles or visible flame from a fire. 

Warning Device Summary Use warning devices such as radiation alarms, fire alarms, intercom systems, and emergency lighting to warn of potential hazards and identify appropriate emergency response procedures. 

Fire detection/fire alarm systems consist of different types of fire detection devices and fire alarm systems. These systems may detect fire, heat, smoke, or a combination of any of these. For example, a typical fire alarm system might consist of heat sensors, which are located throughout a facility and which detect high temperatures or a... 

Emergency alarm system design and installation should be in accordance with NFPA 72. Electrical aspects of the fire alarm systems should be designed and installed in accordance with NEPA 70. When devices are located in hazardous areas, they should meet the electrical requirements suitable for that hazardous area. 

A wide variety of sensing and initiating devices are available that can detect heat, smoke, radiant energy, and fire gas products. These devices should be selected based upon the type of fire anticipated. Additionally, sprinkler system water flow, activation of other extinguishing systems, and manual fire alarm pull stations can also be used to initiate an alarm signal. 

Provide safety and alarm devices, such as fire-alarm systems, combustible-vapor detectors, flame arresters, pressure-relief venting of equipment, flame-failure controls for oil- and gas-fired equipment. 

Some of the more common engineering controls are fire alarms and detection systems, toxic gas alarms and detection systems, redundant alarms and shutdown devices, automatic shutdown devices, and process containment systems. 

In a manual fire alarm system, the device used to activate the alarm in most cases is a pull box or pull station. The mechanism is very simple—puUing the switch either makes or breaks an electrical circuit which in turn causes an alarm to sound. As wiU be discussed more fiiUy in the next section, the alarm may sound only in the individual building, or the alarm could initiate a signal at a remote location as well. 

Everyone should be familiarwith the location anduseofaUequipment in their laboratory area. As noted above, this includes means to initiate an evacuation (fire alarm pull stations, etc.), fire extinguishers, fire blankets, eyewash stations, deluge showers, first aid kits, spiU kit materials, respiratory protective devices, and any other materials normally kept in the area for emergency response. 

A laboratory worker removed the shield from a high-powered microwave-generating device. Fortunately, the emissions triggered the fire alarm system, prompting an evacuation of the laboratory. Had the exposure continued, the person could have suffered severe injury. 

Safety equipment, including spill control kits, safety shields, fire safety equipment, respirators, safety showers and eyewash fountains, and emergency equipment should be available in well-marked, highly visible locations in all chemical laboratories. Fire alarm pull stations and telephones with emragency telephone numbCTs clearly indicated must be readily accessible. In addition to the standard items, thwe may also be a need for other safety devices. It is the responsibility of the laboratory supervisor to ensure proper training and provide supplementary equipment as needed. 

A device for the detection and notification of a fire event. Fire alarms can be activated by people or antomatic devices that can detect the presence of fire. These include heat-sensitive devices, which are activated if a specific temperature is reached a rate-of-rise heat detector, which is triggered either by a quick or a gradual escalation of temperature and smoke detectors, which sense changes cansed by the presence of smoke, in the intensity of light, in the refraction of light, or in the ionization of air. The arrangement and type of fire detectors for optimum performance is usually specified by fire codes or industry guidelines. 

If volume of traffic requires them to be open, retain in open position by automatic device which releases when fire alarm activated... 

All systems should receive a visual inspection each quarter. Test or inspect each antomatic system on an annual basis. Include all systems in the preventive maintenance plan. Test all snpervisory signal devices except valve tamper switches on a quarterly basis. Test valve tamper switches and water flow devices semiannually. Test duct detectors, electromechanical releasing devices, heat detectors, manual fire alarm boxes, and smoke detectors on a semiannual basis. Test occupant alarm notification devices to inclnde andible and visible devices at least annually. Maintain appropriate documentation on all tire-related system testing. 

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