The fire warning system is one of the components of fire protection equipment. According to the fire safety standards of the Russian Federation, any building must be equipped with such a system.
Definition
The fire warning system is a set of organizational measures aimed at quickly alerting people about a possible danger, as well as probable escape routes from a building. Such a system is installed along with a fire alarm. Most of them are equipped with devices to improve sound quality and emergency broadcasts. You can send the necessary notice using any of the internal telephones. To do this, just dial a special code number. Sometimes in large enterprises this system is used to search for a specific employee.
Types
There are five types of these systems, and their choice depends on the regulatory framework and, secondly, on the wishes of the customer.
- Sound notification. This is a tinted signal, signal siren, etc.
- Light warning. Flashing signs with the inscription act as light icons"Exit" with a drawn sign.
- Light warning and speech. Along with the "Exit" icons, people are notified through the speakers about the necessary actions.
- Light warning, voice, simple zone notification and zone notification with the possibility of feedback from the dispatcher.
- Light warning, voice, zone notification with the possibility of feedback from the dispatcher, the implementation of several notifications at the same time, all systems are coordinated from the control post.
The sound warning system is the most reliable and convenient way to inform workers about a fire or other emergency, broadcast special news or even congratulations.
Components of the Public Warning System
The simplest warning and evacuation control system includes: a microphone, a loudspeaker (one or more), an amplifier. More complex ones can additionally include zone selection modules, mixing modules, and other blocks, based on the project and technical specifications.
Speaker types
When choosing a specific loudspeaker of the public address and evacuation system, one should rely on the conditions of its future work: in what place it will be used, on the street or indoors, only messages or also musical compositions will be broadcast, what acoustic characteristics the room has, where installation is planned.
Today manufacturers are ready to offerto a potential buyer loudspeakers of various shapes, sizes and capacities. In all this abundance, you need to sort it out somehow. The easiest way is to divide them into basic types:
- Horn type loudspeakers. They are used in open areas and in production. These loudspeakers are characterized by high sound pressure. They are used only for announcements due to the narrow range of reproducible frequencies. They differ from ordinary loudspeakers in that they have a much smaller angle of emission of sound waves. Mounted on supports, towers, poles, facades of buildings. Used in production halls and other similar areas where the noise level is high.
- For outdoor installation. At such sites, dust and moisture-proof loudspeakers are used that can operate in a wide temperature range. It is these parameters that should be given special attention when choosing this type. The degree of dust and moisture protection must be equal to IP-34. Temperature range -25°С - +40°С. Such requirements are met by loudspeakers with housings made of heat-resistant plastics or metal. The mount allows you to change direction in one of two planes.
- Suspended loudspeakers. This type is widely used in rooms with high ceilings. Their design allows installation on the required
- For wall mounting. This type is not as popular as wall-mounted or ceiling-mounted loudspeakers. This is due to the difficulties of installation work. So, in a brick wall, you will need to prepare a niche, and not each of them has the necessary thickness so that this niche has sufficient depth. Installation in drywall is carried out using springs, which are located in a pre-prepared hole.
- For suspended ceiling mounting. Widely used, suitable for rooms with any configuration. The main condition is the presence of a false ceiling. During the design process, special attention should be paid to the overall dimensions of the loudspeakers and their height, which should not exceed the distance between the main and false ceilings. Such devices are mounted using springs that fix them in a hole prepared in the ceiling.
- For wall mounting. Very popular due to ease of installation and compatibility with various types of interior. Mounted with dowels, which are attached to the walls.
- Special loudspeakers (intrinsically safe, explosion-proof, etc.). The public address system in mines is supplied with this type. And also in industrial premises and in open areas where there is or may form explosive mixtures. This type hasthe highest security, but its cost is quite high.
height, which ensures the uniform sound coverage of rooms of the most complex configuration. Such devices are used in trading floors with uneven or simply high ceilings. That theyorganically fit into the design of the room, they are installed on the same level with the lighting fixtures. This makes the speakers almost invisible, but perfectly audible. They are attached to the elements of metal structures or beams.
Frequency range
The range of reproducible frequencies allows you to divide all loudspeakers into broadband and narrowband. The first ones have good sound quality and rather high cost. They are used where, in addition to voice messages, it is necessary to broadcast music programs. These are sports complexes, shopping and entertainment centers, supermarkets. The voice warning system, as a rule, is composed of devices of the second type. The main task of such audio devices is to transmit only voice messages. These loudspeakers successfully combine average sound quality and a fairly low cost.
Certification of warning systems
Both foreign and domestic manufacturers must certify their products of this type without fail for compliance with fire safety standards of the Russian Federation. Verification of warning systems includes tests for operability in various operating modes, electromagnetic compatibility, mean time between failures, resistance to ignition, etc. Certifies the GU TsSA OPS GUVO MVD (Certification Body for Technical Intruder Alarms of the Russian Federation).
Design
The general procedure for drafting warning systems is established by fire regulations. The project should provide for the possibility of integrating the civil defense warning system and this system. Both of themmust be switched on by a command pulse generated by a fire alarm.
When dividing the building into zones, the designer should develop a special sequence for notifying employees who are at the enterprise. The size of such zones, the order of notification and the time of its start are determined using the conditions for the safe evacuation of workers in a fire hazardous situation.
Alert system. Mounting
Installation of voice alarms in protected areas should be carried out in such a way as to exclude uneven sounding and concentration of sound waves. These devices must not have volume controls and must be connected to the mains without plugs.
The fire alarm system should operate for as long as it takes people to leave the danger areas or building.
Sound signals of the warning system should differ in tone from sounds for other purposes.
The fire alarm system must be controlled from the control room (fire station) or other premises that meet fire safety standards and are duly approved.
How to write emergency messages correctly
To broadcast such messages, it is better to use a pre-prepared recording, since the unrestrained speech of the dispatcher can only increase the panic of people in a critical situation. In addition, psychologists recommend using a calm female voice, since its spectrum is in good agreement with the frequency range important forperception. The text of the message should sound neutral and suppress panic, contain information about evacuation routes from the building. To attract attention, you can send a tone at the beginning and at the end of the message.
