Fire alarm system. What is a voice alarm system?

The fire alarm system is one of the components of fire and technical protection. According to the fire safety standards of the Russian Federation, any building should be equipped with such a system.

Definition

The fire alarm system is a set of organizational measures aimed at prompt notification of people about possible danger, as well as possible ways of evacuation from the building. This system is installed together with the fire alarm system. Most of them are equipped with devices to improve the sound quality and emergency broadcast. You can send the required notification by using any of the internal telephones. To do this, it is enough to dial a special code number. Sometimes in large enterprises this system is used to find 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.

1. Sound notification. This is a tinted signal, an alarm siren, etc.
2. Light notification. As the light icons are flashing signs with the inscription "Exit" with a drawn pointer.
3. Light warning and speech. Along with the icons "Exit", people are informed through the columns about the necessary actions.
4. Light notification, voice, simple zone notification and zone notification with the possibility of feedback from the dispatcher.
5. Light warning, voice, zone notification with the possibility of feedback from the dispatcher, the implementation of several alerts simultaneously, all systems are coordinated with the dispatching post.

Sound warning system is the most reliable and convenient way to inform workers about a fire or other emergency situation, the transfer of special news or even congratulations.

Components of the public alert system

The simplest warning and evacuation control system includes: a microphone, a loudspeaker (one or several), an amplifier. In more complex zones, zone selection modules, mixer modules and other blocks can be additionally included, based on the project and the technical assignment.

Types of loudspeakers

When choosing a particular loudspeaker, the warning and evacuation systems should be based on the conditions of their future work: in which place it will be used, on the street or in the room, only messages or musical compositions will be broadcast, and the acoustic characteristics of the room where the installation is planned.

Today, manufacturers are ready to offer the potential buyer loudspeakers of various shapes, sizes and capacities. In all this abundance you need to sort it out. The easiest way is to divide them into main types:

1. Loudspeakers horn type. Are applied in the open territories and on manufacture. These loudspeakers are characterized by high sound pressure. Used only for the transfer of ads due to a narrow range of reproduced frequencies. They differ from conventional loudspeakers and in that they have a much smaller angle of radiation 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.
2. For installation in open areas. At such sites, dust-proof loudspeakers are used, capable of operating over a wide range of temperatures. It is these parameters that should be given special attention when choosing this type. The degree of dust protection should be equal to IP-34. The temperature range is -25 ° С - + 40 ° С. Such requirements can withstand loudspeakers with enclosures made of heat-resistant plastics or metal. Mounting allows you to change the direction in one of the two planes.
3. Suspended loudspeakers. This type is widely used in premises with high ceilings. Their design allows for installation on the required Height, which ensures the uniformity of sound coverage of the premises of the most complex configuration. Such devices are used in trading halls with multi-high or simply high ceilings. To ensure that they fit seamlessly into the design of the room, they are installed at the same level as the lighting fixtures. This makes the speakers almost invisible, but perfectly audible. They are attached to the elements of steel structures or beams.
4. For installation in a wall. This type is not as popular as wall mounted or suspended in a suspended ceiling 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 had a sufficient depth. Installation in gypsum board is carried out with the help of springs, which are located in a pre-prepared hole.
5. For installation in a false ceiling. Widely used, suitable for premises with any configuration. The main condition is the presence of a false ceiling. In the design process, special attention should be given to the overall dimensions of the speakers and their height, which should not exceed the distance between the main and suspended ceiling. Such devices are mounted with the help of springs, which fix them in a hole prepared in the ceiling.
6. For wall mounting. Very popular, which is due to the ease of installation and compatibility with various types of interior. Mounted with dowels, which are attached to the walls.
7. Special loudspeakers (intrinsically safe, explosion-proof, etc.). The system of voice notification in mines is supplied with this type. And also in industrial premises and on open areas, where there are or may form explosive mixtures. This type has the highest security, but its cost is quite high.

Frequency range

The range of reproduced frequencies allows you to divide all loudspeakers into broadband and narrowband. The first ones have good sound quality and quite high cost. They are used wherever other than voice messages you need to broadcast music programs. These are sports complexes, shopping and entertainment centers, supermarkets. As a rule, the system of voice notification is composed of devices of the second type. The main task of such audio devices is the transmission of only voice messages. These loudspeakers successfully combine sound of average quality and rather low cost.

Certification of warning systems

Both foreign producers and domestic producers must certify their products of this type in compulsory order for compliance with fire safety standards of the Russian Federation. The audit of warning systems includes tests on efficiency in various modes of operation, electromagnetic compatibility, mean time to failure, resistance to ignition, etc. Certification of the CA CAA OPS GOVO MVD (Body for certification of technical security equipment RF).

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 notification system and this system. They must both be activated by a command pulse, which forms a fire alarm.

Separating the building into zones, the designer should develop a special order of alerting employees who are in the company. The size of such zones, the order of the alert and the time of its start are determined by the conditions of safe evacuation of workers working in a fire hazardous situation.

Notification system. Installation

Installation of voice annunciators in protected areas should be conducted in such a way as to exclude uneven sound and concentration of sound waves. These devices should not have volume controls, and they must be connected to the mains without plug-in devices.

The fire alarm system should work as long as people need to leave the hazardous areas or building.

The sound signals of the notification system in their tonality must differ from the sounds of another purpose.

The fire alarm system should be managed from the control room (fire station) or other premises that meet the fire safety standards and are approved in due order.

How to draw up emergency messages

To broadcast such messages it is better to use a pre-prepared record, since the dispatcher's speech can only aggravate 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 that is important for perception. The text of the message should sound neutral and suppress panic, contain information about evacuation routes from the building. To attract attention, you can transmit a tone at the beginning and end of the message.