5.2 Analysis of dangerous and harmful factors

The standard of the classification of dangerous and harmful factors, is GOST 12.0.003-74 *.human body may have physical, chemical, biological and physiological effects. When working with a personal computer (PC) and the server, the user in varying degrees, can affect the following physical factors: elevated levels of alternating electromagnetic and electrostatic fields, elevated levels of static electricity, the high content of positive ions in the air of the working area; reduced levels of negative ions , high or low level of illumination of the working area, high brightness light image fragments or light incident in the field of view, increased ambient light screen, increased direct glare caused by getting into the field of view of working excessively bright light emitting various facilities, increased reflective glare caused presence of specular reflections, including the screen having a high brightness, high voltage electrical circuit, which circuit may occur through the human body, fire, etc. The group of biologically harmful factors that can cause deterioration of the disease or health of the user, is the high content of air in the working area of ​​pathogenic microorganisms (bacteria, viruses, etc.) They may appear in a room with many operating with insufficient ventilation, for example, during the epidemic.[9]

5.3 Production sanitation and health

Under the influence of the equipment and processes in the work area, a certain external environment. Climate is characterized by the content of hazardous substances, noise, vibration, radiation, light workplace. All sanitary factors quantitatively measured and normalized according to the standards.

Requirements to noise and vibration. When the main work in all areas of the personal computer and the server noise in the workplace should not exceed 50 dB. Dinning equipment (printers, etc.), which exceed the noise levels normalized, should be outdoors with a personal computer and a server. In the laboratory, "NIT" noise level does not exceed 50 dB when all PCs and servers are working.

Lighting requirements of premises and workplaces. The illumination on the table in the zone of the working paper should be 400lk. Should be limited to the direct glare from light sources, and the brightness of the illuminated surfaces (windows, light fixtures, etc.), within the field of view, should be no more than 200 C/m2. It is necessary to limit the reflected glare on work surfaces (screen, desk, keyboard, etc.) by proper selection of lighting fixtures and layout of workplaces in relation to sources of natural and artificial light, and the brightness of the glare on the screen of a personal computer should not exceed 40 cd/m2 and the brightness of the ceiling, the application of indirect lighting shall not exceed 200 cd/m2. Glare factor for the sources of artificial lighting in common areas should be no more than 40 to 25 classrooms. Should be limited to the uneven distribution of brightness in the field of view of the user PC with the brightness ratio between the working surfaces must not exceed 3:1 - 5:1, and between the working surfaces and wall surfaces and equipment 10:1. Brightness lamps for general lighting in the area of ​​radiation angles from 50 degrees to 90 degrees to the vertical in the longitudinal and transverse planes should not exceed 200 cd/m2, protective corner lamps must be at least 40 degrees. Local lighting fixtures should not be translucent reflector with protective angle of at least 40 degrees. Ripple should not exceed 5%, which should be achieved by the use of gas-discharge lamps in luminaires general and local lighting with high frequency ballast (HF) for all types of lamps.

In the laboratory applied artificial lighting. Laboratory has 4 fluorescent lamps. Fluorescent lamps have a higher light output compared to incandescent bulbs, more natural spectral composition of the radiation and longer life. Glass flask filled with mercury vapor and phosphor coating on the inside that converts the UV radiation of the gas discharge in the visible. Fluorescent lamps differ in size, shape, and spectrum of the radiation.

Types of radiation: radio, infrared, visible light, ultraviolet light, and ionizing radiation. All these types of radiation, has an electromagnetic nature different wavelength, frequency and energy. Ionizing radiation can be from the desktop. It is recommended, for example, to display the user's eye was from a distance no closer than 50-70 cm. Minister of Health of the Republic of Kazakhstan from September 28, 2010 № 767 of continuous operation with a PC should not exceed 2 hours

Thermal radiation - is electromagnetic radiation emitted by matter and occurs due to the energy of thermal motion of atoms and molecules (ie, the internal energy). The source of radiation can be computers and server.

In industrial environments, where work on the PC is the main should be provided with the optimal parameters of the microclimate. During the cold period of the day the optimal parameters of the microclimate of the laboratory: air temperature 21-24C, humidity 40-60%, air velocity of 0.1 m/s. In the warm period of the day the optimal parameters of the microclimate of the laboratory: air temperature 22-25C, humidity 40-60%, air speed of 0.1 m/s.

Ventilation - a set of interconnected devices and processes designed to create an organization of ventilation, consisting in the removal of contaminated industrial premises or superheated (cooled) air supply instead of clean and cold (hot) air, which poses will create in the work area favorable ambient air. In the laboratory "NIT", used the mechanical ventilation. Exhaust systems for mechanical ventilation or remove the dust-laden air is polluted gases at any distance from the workplace or the shop, as well as clean the air of dust before throwing it into the atmosphere. Supply and exhaust systems can be turned on and off at any time, their work supervises staff. Because of these advantages, mechanical ventilation is more widely used than the natural.

5.4 Electrical safety

In the PC and server source of danger is the electric part, namely, the input circuits of the power supply, which can be connected to the current industrial voltage 240 V, 50 Hz, with isolated neutral. Output circuit of the power supply is 15 ± 5V. Consequently, according to electrical codes (PUE) 1.1.3 device belongs to installations with a rated voltage up to 1000V to use the premises from a PC belongs to a class of premises without heightened risk from the point of view of the risk of electric shock. Ambient temperature of room must be +20 ± 5, relative humidity of 60 ± 20%. The room must be non-conductive floors, conductive dust absent, absent electrically active environment, absent the ability to simultaneously touch the metal parts of the instrument and electrical grounding, missing the heat and humidity (PUE 1.1.13). To protect against electric shock, all live parts shall be protected against accidental contact housings (PUE 1.1.32), the device must be grounded. Grounding is performed insulated copper wire 1.5 mm2 (PUE 01/07/78), which is attached to a common ground bus with a total cross-section of 48 m2 by welding. Overall tire attached to the ground, the resistance of which should not exceed 4 ohms (PUE 1.7.65). Meals must be made from the power board through the circuit breaker will be triggered when a short-circuit load.

5.5 Fire safety

The rooms in which are installed PCs, the fire hazards are related to the category D, and shall meet the requirements for the prevention and suppression of fire in accordance with GOST 12.1.004-91. To prevent fire in the zone of conventional PC combustible materials (paper) and electrical equipment, you should take the following measures: use dry chemical OP-5. Powder extinguishers are used to extinguish fires of almost all classes, including the electric equipment under voltage up to 1000 V. Their application depends on the type used in the extinguisher powder. Today it is the most common type of fire extinguishers. Temperature range of them can reach values ​​of -50 to 50 C °. These extinguishers can put out a small fire, electrical, combustible gases and liquids. Inside there is a special extinguisher powder which when sprayed on the surface of the film creates a burning object. Powder contained in OP irritates the respiratory system, so while working with him to use a protective bandage. Fire safety measures are defined in ISO 12.1.004-91. Members are allowed to work on the PC only receive instruction on safety and fire safety in the laboratory as a whole and in every workplace.