Installation of security and fire alarm systems: requirements, installation stages

What is this?  Security and fire alarm is a hardware and software complex that includes sensors, detectors, control panels, cables, and equipment for the control room. Serves for timely notification of fire and fire prevention.

How to install?  The installation of such systems is subject to a set of rules and regulations. Specialized organizations deal with it. Installation of a security and fire alarm system takes place in several stages: inspection of the facility, design of the complex, installation and configuration of equipment.

What is a fire alarm system?

A security and fire system (SFS) is usually called a set of special-purpose devices mounted on a protected object, which are components of a technical complex. Its purpose is to provide conditions for timely notification of possible fires and other incidents that may pose a danger to visitors and staff.

Installation of security and fire alarm systems allows you to make protected premises safe, preventing fires that could not only create a danger to the life and health of people, but also cause harm to the buildings themselves and the material assets stored in them.

All fire and security alarm systems include two parts combined into a single system:

• The first includes sensors that are mounted both inside and outside rooms and buildings. These devices detect changes in temperature, smoke, movement, carbon monoxide, or attempts to enter through broken windows.
• The second mandatory component of security and fire systems - the executive one - collects and processes data received from sensors.

The dispatch console is equipped with indicators that display signals from the devices included in the fire and security system, so the operator has the opportunity to promptly respond to unauthorized entry or fire. As a rule, indicators are placed on plans of specific premises or buildings.

The semi-automatic mode of operation of the alarm system requires the operator to manually turn on the warning system, as well as activate voice and visual channels for transmitting messages about emergency situations.

If the danger is confirmed, the system that controls access to the facility, after receiving an alarm signal, initiates the transfer of all structures located in the building or premises to evacuation mode. In parallel with this, the same notifications are sent to utility networks to temporarily block them.

The automatic mode of operation of professionally installed security and fire systems provides for the performance of a number of functions without human intervention. Such OPS can:

• accurately determine the location of fires;
• identify lesions after receiving a repeated signal;
• identify damage that occurs in networks due to short circuits or broken lines, accurately linking them to the site plan;
• detect fire at the initial stage;
• manage the processing of incoming signals and data, displaying the results to control panels.

Security and fire alarms can display sensor signals, displaying them on plans with varying degrees of detail. It is possible to display incoming information on control panels - both in the form of text messages and in graphic format.

Which organizations need to install fire alarm systems?

Installation of a security and fire alarm system is required:

• in kindergartens, schools, sanatoriums, clinics, rest homes, entertainment and leisure centers, children's sports schools, creativity and development centers;
• in medical institutions, clinics, private practices, hospitals and diagnostic centers;
• in hotels, hostels, dormitories, apartments and rooms for rent;
• in shopping centers, shops, warehouses, production and technical premises, parking lots and underground parking lots;
• at enterprises providing personal services (hairdressers, beauty salons, health and beauty centers, swimming pools, studios, repair shops);
• in entertainment and cultural institutions (cinemas, theaters, circuses, zoos, attractions and other entertainment centers);
• in catering establishments, cafes, canteens, restaurants;
• in office premises and business centers, in banks and their branches, in municipal and government institutions, in police departments;
• in educational and scientific centers, in laboratories, in production.

In other words, the installation of fire safety systems is mandatory for all premises intended to be visited by people.

Composition of the fire and security alarm system

Detectors (sensors)

To detect alarm events in security and fire alarm systems, detectors are used that operate on various principles and are triggered by temperature changes, movement, smoke, sound, vibration, etc.

The type of detectors used in fire and security alarms depends on what type of system it belongs to.

Detectors used in alarm (security) alarms can be:

• magnetic contact (reed switch) - triggered by opening a door or window;
• acoustic - responding to the sound of broken glass;
• vibration – controlling mechanical impacts on building structures;
• motion detectors - infrared, ultrasonic or microwave.

The following sensors are installed in fire alarms:

• smoke;
• heat;
• flame.

Electrical impulses are used to transmit signals from sensors to control panels. For the simplest analog devices, these are threshold-type notifications that report the presence or absence of contact. More modern electronic detectors provide digital transmission of information. Switching channels are cables (loops) or radio waves of certain frequencies.

PKP – control and control devices

The classification of such devices is carried out on the basis of various parameters - the most often used are:

• information capacity;
• informative.

Information capacity depends on the maximum number of devices with which the device can work (individual addressable detectors or common loops in threshold-type systems).

The information content of the control panel depends on the number and type of information signals that the device can output to the indicator or liquid crystal panel. In the simplest devices these are “norm” and “alarm”. In more complex ones, the response zone can be displayed, the health of connected detectors can be determined, etc.

Fire resistant cables for fire alarm loop

According to the requirements of GOST R 53315-2009, such a cable must operate at high temperatures and under the influence of open fire for at least three hours, which allows evacuation measures to be carried out and the location of the fire to be accurately determined.

Cables for fire alarm loops are selected according to:

• fire resistance limit  – the ability to transmit electrical impulses under conditions of direct exposure to fire;
• degree of flammability  - non-flammable insulation of wires is marked with the letters NG;
• toxicity  - the percentage of carcinogens and poisons that are released under the influence of an open flame.

During the tests, the cable is exposed to a gas burner flame (+700 degrees Celsius) for 180 minutes.

Rules and stages of installation of security and fire alarm systems

When installing an alarm system, it is necessary to take into account the type of protected object - its purpose, area, ceiling height, etc. The general rules state:

• When installing, you must follow the instructions for specific devices.

  Input connectors are used to connect sensors in simple systems. More complex ones are additionally equipped with security functions.

• When laying the line, it is necessary to take into account the requirements of building codes and regulations.

  The cables must be made of copper wire and have heat-resistant insulation. The sensors are connected with two-wire or four-wire wires. The supply of loops when installing security and fire alarms should reach 10%. In accordance with fire safety requirements, joint laying of connecting wires and power cables is allowed.

• Fire detectors are installed in areas of potential fires.

  Adjacent points should be 9 m apart. The distance from the sensor to the corner is 4,500 mm, to the ceiling - 200 mm. Thermal sensors should not be mounted near heating devices. Linear detectors are installed on opposite sides of the premises.

Self-installation of fire alarm systems is not permitted - it is carried out by representatives of specialized organizations in accordance with the design documentation. Installation is carried out in several stages and includes:

• project preparation;
• equipment configuration in accordance with the type of fire alarm;
• laying lines;
• connection of detectors;
• setting up and launching a security and fire alarm system.

During preparation for installation, the facility is examined in order to select the optimal alarm structure. Based on the data obtained, a technical specification is drawn up, which must be agreed upon with the customer before installation.

Particular attention should be paid to laying lines. Cables and cables must be resistant to fire.

Marking of wires for fire alarms may contain the following parameters:

• NG – does not spread fire (group gasket);
• LS – low smoke level;
• HF – halogen-free;
• LTx – low toxicity;
• FR – increased fire resistance.

When laying OPS lines, it is necessary to maintain the following distance:

• from the floor – 2,200 mm;
• to the ceiling - at least 100 mm;
• between the cable and power cables – 500 mm;
• if a low-current line intersects with a power cable, the wires must be protected with a PVC pipe 500 mm in each direction;
• fastening clips are located every 250 mm horizontally and 350 mm vertically.

To install the control panel, separate boxes are used, which can be located at an arbitrary distance from the floor. If the control panel is located in an area freely visited by employees, special lockable protective cabinets made of non-flammable material are used. Such boxes are also necessary in dusty and humid areas.

When developing design documentation for security and fire alarms, it is necessary to take into account the required number of detectors, which is calculated taking into account the specifics of specific objects, but in any case cannot be less than two.

Heat and smoke sensors are mounted on the ceiling. If the room has suspended ceilings, they can be installed on a wall or column. The distance to the ceiling should be from 100 to 300 mm. If there are niches in the ceiling, detectors must be placed in each of them. Manual devices are located near exits from premises at a height of 1,500 mm from the floor.

Designing the installation of a security and fire alarm system is not always individual - more often the fire alarm system is included in standard projects.