Area smoke detectors

Area smoke detectors are generally installed in buildings and accommodation areas. Where this is not practical—say in the galley area—other types of fire detector should be used. Actuation of a single smoke detector will initiate a fire alarm. If additional detectors sound an alarm, the equipment in the area of the fire and HVAC systems will be shut down. 

The ambitious goal of eBuilding is to maximize the comfort of the house owner at a minimum cost level. This will be achieved by using sensors in all sensitive areas, for instance, constant control of the air-conditioning or to cut off cost intensive peaks. Also sensors in smoke-detectors, windows, doors and other appliances will take care of the house security. 

Sprinkler systems are an effective way to contain fires. The system consists of an array of sprinkler heads connected to a water supply. The heads are mounted in a high location (usually near ceilings) and disperse a fine spray of water over an area when activated. The heads are activated by a variety of methods. A common approach activates the heads individually by the melting of a fusible link holding a plug in the head assembly. Once activated, the sprinklers cannot be turned off unless the main water supply is stopped. This approach is called a wet pipe system. These systems are used for storage areas, laboratories, control rooms, and small pilot areas. Another approach activates the entire sprinkler array from a common control point. The control point is connected to an array of heat and/or smoke detectors that start the sprinklers when an abnormal condition is detected. If a fire is detected, the entire sprinkler array within an area... 

Specifically, they tell them these things A smoke detector should be placed on each floor of a home. While sleeping, people are in particular danger of an emergent fire, and there must be a detector outside each sleeping area. A good site for a detector would be a hallway that runs between living spaces and bedrooms. 

Smoke detectors should be located and spaced to ensure prompt detection under incipient fire conditions. Spacing requirements should consider the type of detector used, manufacturer recommendations, geometry of the protected area, and effects of air handling equipment. See NFPA 72 for more information on spacing. 

Ionization smoke detectors can be used in general accommodation areas such as corridors and public restrooms, to monitor the escape routes. They may be used in some types of equipment spaces, depending on ventilation. 

The location of the smoke detectors should be based on an engineering survey of the area to be protected. Factors such as air flow, proximity to airhandling system diffusers and other physical features of the installation need to be taken into account. Smoke tests can be run to verify that the air flow within the protected area favors the smoke detectors. 

If the MCC will be located within an electrically classified area, the ventilation system must be designed, operated and maintained to create a positive pressure inside the MCC building and the air intake located outside of the electrically classified area. The MCC should be equipped with smoke detectors and alarmed to a constantly attended location. CO2 fire extinguishers are the suggested protection for MCC rooms. The storage of combustible materials inside an MCC must be prohibited. 

If you do purchase a commercially available carbon monoxide detector, make sure that it meets Underwriters Laboratories Inc. (UL) standards. As is the case with smoke detectors, carbon monoxide detectors should be installed close to sleeping areas. 

As indicated above, the spread of fire and smoke can be controlled by both passive and active means. On the one hand, the measures include separation of buildings com-partmentation fire walls fire doors fire and smoke shutters controls on air conditioning and pressurization of critical areas such as stairways and, on the other, detectors and alarms extinguishers hose reels and sprinkler systems. Smoke detectors generally detect fire more quickly than heat detectors. 

The increase in break-ins has led to pressure for better domestic security, not least from insmance companies. People in high crime areas will have extra locking devices fitted to doors and windows. However, these can restrict ability to escape in a fire. It is essential to ensure ready escape in a fire. In poorer areas, fires can result from not being able to leave children supervised, or from using unsafe low cost heating. Not having a smoke detector is an additional risk. Better domestic fire safety will result if ... 

A fire eye or flame detector detects the radiation from a flame. It requires line-of-sight capability. There must be no blockages between the instrument and the potential fire locations. A fire eye s field-of-vision usually covers a larger area than that of a heat detector, but it will not detect a smoldering fire as quickly as some smoke detectors. 

Radiation detectors generally complement heat and smoke detectors, especially in tall, unobstructed compartments and are effective in special applications such as flammable liquid storage areas. 

Normal heat and smoke detectors rely on the presence of convection currents caused by the fire to carry either the products of combustion or heat past the detector which is usually mounted at high level. If there is little heat from the fire then there can be a significant delay before the detector receives enough information from the fire to actuate the alarm. Carbon monoxide detectors overcome this problem since the carbon monoxide produced by the fire dissipates into the atmosphere of the protected area and... 

A development to replace halon systems has been water mist systems in which a system of open discharge heads is used. The system is actuated by smoke detectors located witiiin the area to be protected. Operation of one detector raises the alarm and it requires a second detector to be actuated before the water is released into the discharge pipework. Water for the system is stored in cylinders at high pressure and the discharge heads are designed to produce a fine water mist. Water mist systems use significantly less water than a sprinkler system and extinguish fires by ... 

Dopable conjugated polymers have been investigated as both chemical and biochemical sensors - wherein changes in electrical conductivity of the polymer provide the device response.Initial efforts in this area dealt with smoke detectors, where the motivation was to elimi-... 

Sampling Detectors. These consist of tubing distributed from the detector unit into the area(s) to be protected. An air pump draws air from the protected area back to the detector. A high-intensity strobe, laser particle counter, or cloud-chamber smoke detector may be used... 

Area smoke and heat detectors. Hazardous production material storage rooms are required to have a supervised smoke detection system in accordance with the above UFC requirements. We recommend the installation of heat detectors in all electrical rooms. 

Pre-action sprinkler system - this is a combination of a standard sprinkler system and an independent approved system of heat or smoke detectors installed in the same area as the sprinklers. Like dry pipe systems the pipes are filled with air but water is only let into the pipes when the detector operates. Pre-action systems... 

Heat detectors - these detectors operate by sensing heat in the environment. They operate in two distinct ways. Some are designed to operate at a given temperature whereas others detect the rapid rate of rise of temperature that is associated with a developing fire. They are often used in a kitchen area, where smoke detectors would continually actuate because of the normal processes in a kitchen area. 

As soon as possible after the false alarm, inspect that area and locate the break glass box, heat detector or smoke detector that set off the alarm in order to ascertain why the alarm was triggered. It should be noted that the detector may be in a duct or above a false ceiling. It will be necessary to call in a competent engineer to assist the process on those occasions when ... 

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