Failure to comply with the sanitary and hygienic requirements of the computer. Hygienic requirements for organizing work with a personal computer. Workplace requirements

On modern enterprises The work of many office employees involves spending a long time at the computer. In accordance with current standards, the negative impact of a computer monitor has a significant impact on the employee’s body, which can be regarded as a harmful factor in working conditions. In this case, the duration of interaction between the employee and the computer will be taken into account first of all.

The employer is entrusted with the responsibility to properly organize the workspace of employees who work with computer equipment throughout the entire day or part of it. Requirements regarding working conditions for PC users are enshrined in the current legislation. According to them, employees who work at a computer more than 50% of their working time are considered to be involved in work under hazardous conditions.

If, during the certification of production areas, these workplaces are identified as having harmful and/or dangerous working conditions, then the employees performing their job responsibilities, will be entitled to payment of appropriate compensation. If, based on the results of the assessment, the presence of negative facts is not established, then compensation for employees is not provided.

In addition, for persons involved in work with hazardous and/or harmful exposure factors, a mandatory primary medical examination and annual re-examination are provided. This measure is necessary to confirm their ability to fully perform job duties and prevent the occurrence of occupational diseases.

Classification of the degree of harm from working on a computer according to current legislation

In the main regulatory act regulating the relationship between employer and employee - the Labor Code of the Russian Federation - there are no rules that provide for the possibility of classifying long-term work at a computer as having harmful exposure factors. Because of this, in practice, situations often arise in which sanitary and hygienic requirements for the working conditions of employees are neglected.

However, despite this, these requirements are enshrined in a number of other regulations. The Standard Instruction for OT No. R-45-084-01 sets out negative factors that can have an impact on the body of employees who work with a computer for a long time:

Low level of air ionization;
Increased performance electromagnetic radiation and static electricity;
Increased load on the worker’s vision;
Prolonged static physical stress.

In addition, prolonged sitting in a sitting position often leads to venous insufficiency, curvature of the spine, poor vision and chronic stress. However, most of these problems can be avoided by proper organization workspace. Therefore, the requirements regarding the equipment of workplaces for PC users include providing the correct furniture, creating comfortable microclimatic conditions and required level lighting.

Among the regulations governing sanitary and hygienic working conditions with computers, in addition to the above Standard Instructions:

SanPiN 2.2.2./2.4. 1340-03;
Order of the Ministry of Health and Social Development of the Russian Federation No. 302n;
Order No. 426-FZ.

As for the norms of the Labor Code of the Russian Federation, it sets out the rules regarding the duration of work shifts and mandatory rest breaks (Article 108 of the Labor Code of the Russian Federation). If at the enterprise, during the assessment process, these work sites were identified as having harmful exposure factors, then, according to Article 117 of the Labor Code, employees working on them have the right to receive additional days of annual rest, in an amount of at least seven. The employer has the right to increase the duration of additional leave by fixing of this rule in local acts of the enterprise. Revocation from additional rest is not allowed, nor is its replacement with monetary compensation. The only exception is the channel calculation when an employee is dismissed.

Sanitary standards for working at a computer

As noted above, the rules for organizing a workspace for working at a computer are enshrined in the Sanitary Rules, which regulate the procedure for carrying out work activities using PCs and computers. At the same time, each computer in the company must undergo a mandatory hazard assessment, the results of which are reflected in the certificate of conformity. If an employer purchases this equipment in company stores, then it is tested in a laboratory there, so there is no need to worry about its compliance with safety requirements.

When choosing technology, it is necessary to take into account that it must be able to change the position of the screen, so that the employee can change its position along the horizontal and vertical axis. Frame system unit should be made in soothing colors without shiny elements, since during work they reflect glare, which causes increased strain on the eyesight. In order to reduce eye fatigue, the monitor must have contrast and brightness adjustment so that the employee can set the intensity of light and color transmission that is comfortable for him.

According to the current rules, the employer is obliged to organize the employee’s workplace based on the requirements for:

Premises;
Lighting;
Furniture and other things.

Requirements for premises for working with a computer

Today it is not uncommon to find workspaces with an area of only 10-12 square meters. m, which employs five to six people at a time. However, such working conditions are considered a gross violation of the rules established by SanPiN, according to which the necessary workspaces for an employee who works with a computer more than 50% of his working time, it depends on the type of monitor he uses:

Based on an electro-ray tube, the working area for one worker must be at least 6 square meters. m;
Plasma or LCD monitor - allows you to reduce this figure to 4.5 sq.m.

According to current recommendations, windows in such rooms are best located in the northern and northeastern parts. And if the production area does not have natural light, then the head of the company must provide employees with artificial lighting in the required amount. According to legal requirements, this requires special calculations, which is rarely done in practice.

The placement of employee desks is carried out in such a way that the distance between them is not less than 2 m, and between the side parts of the monitors - from 1.2 m. SanPiN also contains requirements regarding the degree of vibration, the intensity of sound and electromagnetic influences, as well as the microclimate in the room.

Lighting in the workplace

The rules for lighting rooms in which workers who use computers work are covered in SanPiN Special attention. This is due to the fact that the degree of visual fatigue directly depends on the intensity of lighting.

According to the requirements of the Sanitary Rules, it is better to place sources of natural light on the north, north-east side of the room. Artificial lighting it is recommended to organize with the help fluorescent lamps shaped like lines (solid or broken). They should be installed on the side of the working surface, and in case of circular placement of work stations - localized, above the table, closer to the operator. The level of local illumination on the working surface should be within 300-500 lux.

When choosing computer desks to equip your workspace, you need to consider a number of aspects:

The design of the furniture must correspond to the specifics of the work and the number of additional equipment required to perform it;
The table width must be at least 800 mm and no more than 1400 mm;
Depth – from 800 to 1000 mm;
Height – 725 mm.

It is not recommended to use a regular office chair when setting up workstations for PC users, as it does not have the necessary ergonomic properties. The right furniture provides the necessary support for the back and helps reduce stress on this area, as well as the neck and shoulder area. It is better if the chair has a lifting mechanism that allows you to adjust its height.

According to clause 9.3 and clause 10.5 of SanPiN, for computer users who work with them for more than half of their working time, it is necessary to provide a special footrest, up to 15 cm high and 30 cm wide.

In addition, this standard contains requirements regarding the organization of the workspace when implementing creative activities associated with significant mental stress and prolonged concentration. It is better to isolate such areas using opaque partitions with a height of one and a half to two meters.

Work breaks

In order to prevent increased fatigue of employees working with computers, clause 1.3 of Appendix No. 7 to SanPiN recommends, when developing work shifts, to alternate activities with and without the use of a PC. If the job requires constant contact with computer equipment, then you should organize breaks in the work of employees for 10-15 minutes every hour. According to Part 1 of Article 109 of the Labor Code of the Russian Federation, these breaks are included in working time, and during night shifts, the duration of rest increases by 30%.

Before you start, there are a few things to pay attention to:

Do the palm rests interfere with keyboard operation?

how the top edge of the monitor is positioned in relation to the eyes;

what is the height of the work chair (ergonomics);

Is the overall illumination sufficient?

The top edge of the monitor should be level with the eye, the bottom edge should be approximately 20° below eye level. The display should be at a distance of 40-75 cm from the eyes. The screen illumination should be adjusted so that it is equal to the room illumination. When working with the keyboard, the elbow joint is held at an angle of 90°. Every 10 minutes you should look away from the display (for example, towards the window) for 5-10 seconds. It is not recommended to work on the keyboard continuously for more than 30 minutes. At the first sign of pain in your hands, you should immediately consult a doctor. It is better to organize work in such a way that the nature of the operations performed changes during the working day.

Radiation protection. One of the reasons for the deterioration of health among computer operators is the low quality of monitors.

Several years ago, to protect health, special screens were hung on monitors, which, however, did not always weaken the electromagnetic field. Thus, according to the Elite testing center, only two types of filters out of 200 used were certified, some of which were completely transparent to radiation.

When assessing the reliability of a filter, it is necessary to take into account the presence of three components of electromagnetic radiation:

1) electrostatic field, captured almost completely by the filters and removed from them by grounding the protective screen;

the electrical component of the electromagnetic field, not captured by filters, which only create an obstacle to its passage, as a result of which the flow goes around the filter and reconnects at a distance of 1.5 -2 m from it;

magnetic component, practically not captured by filters (up to 5%).

An important measure for protection against radiation is the optimal placement of computers in the workroom (Fig. 4.8).

Rice. 4.8. Placement of PC indoors:

A- irrational (cross-irradiation of workplaces is observed);

Personal protection factors. You can also apply personal protective factors, divided into three groups:

preventive medication measures;

improving conditions for reading information;

shielding the operator entirely or individual areas of his body. The choice of personal protective factors depends on age, health status and length of work.

Preventive medication measures. Considering the fact that when working on a computer, mineral metabolism is disrupted, its normalization with the help of special drinks should be considered an important preventive measure. Preventive drinks are recommended for use by practically healthy adult operators when working no more than 8 hours a day. For example, Profile LLP developed a mineralized drink “Zashchita”, tested jointly with the State Sanitary and Epidemiological Supervision Service of Russia. The drink is produced by the research and production company Combiotech LTD. It is taken 50 ml every 3-4 hours of working with a computer.

Improving conditions for reading information. Preventive glasses with a special coating were developed by Lornet-M JSC and tested by the Moscow Research Institute of Eye Diseases named after. G.L. Helmholtz and the Institute of Biochemical Physics named after. acad. N.M. Emanuel. Glasses reduce eye fatigue by at least 25-30%. They are recommended for use by all operators when working at a computer for more than 2 hours a day, and if vision is impaired by two or more diopters - regardless of the duration of work.

Shielding the operator entirely or individual areas of his body. A protective suit was proposed that completely shielded the operator and was made from Voskhod fabric. It is advisable to use it during pregnancy, as well as for pre-cancer diseases (uterine fibroids, mastopathy, dysfunction of the prostate gland, etc.), which tend to grow.

A protective suit with shielding of only certain areas of the operator’s body ensures the maintenance of health in optimal conditions for 6 hours of continuous operation. A protective cap or bandage shields the forehead and, by preserving the functions of the brain and blood vessels, reduces the deterioration of health from radiation by 5 times. It is recommended to use it regardless of the duration of work.

Hygienic requirements for PC monitors and work organization. IN The premises should have mixed lighting (natural and artificial). Natural lighting in the room is provided through light openings. It is recommended that it be oriented to the north and northeast. The size of the KEO in areas with stable snow cover should be no lower than 1.2%, and in the rest of the territory - 1.5%.

Lighting installations are placed so that they provide uniform illumination. General lighting lamps should be placed above the work surfaces in a uniformly rectangular pattern so that the amount of artificial illumination is at least 300 lux.

The desktop should be height adjustable within the range of 680-800 mm. The optimal width of the working surface of the table is 800, 1000, 1200, 1400 mm with a depth of 800 and 1000 mm. There must be free leg space under the desk with a height of at least 60 cm.

The following requirements apply to the monitor:

a) its size must be at least 13 inches ( 31 cm) diagonally;

b) it must have an anti-reflective coating;

c) jitter on the display should be within 0.1 mm.

The image contrast must be at least 0.8.

The duration of direct work with a computer depends on the availability of skills and the severity of the work and is:

for 1st grade schoolchildren - 10 minutes;

2-5th grades - 15 min;

6-7th grades - 20 min;

8-9th grades - 25 min;

When rationing the number of characters read or entered per shift (the number of characters read is no more than 60,000, and the total number of characters read and entered is up to 40,000 per shift) and with an eight-hour working day, regulated breaks are set every 2 hours for 15 minutes. In order to prevent overwork and overstrain during breaks, it is necessary to perform sets of exercises (for the eyes and muscles of the body).

Employees must undergo preliminary (upon hiring) and periodic medical examinations to prevent occupational diseases.

Before you start, there are a few things to pay attention to:

1) do the palm rests interfere with working on the keyboard?

2) how the top edge of the monitor is located in relation to the eyes;

3) what is the height of the work chair (ergonomics);

4) is the overall illumination sufficient?

The top edge of the monitor should be level with the eye, the bottom edge should be approximately 20º below eye level. The display should be at a distance of 40-75 cm from the eyes. The screen illumination should be adjusted so that it is equal to the room illumination. When working with the keyboard, the elbow joint is held at an angle of 90º. Every 10 minutes you should look away from the display (for example, towards the window) for 5-10 seconds. It is not recommended to work on the keyboard continuously for more than 30 minutes. At the first sign of pain in your hands, you should immediately consult a doctor. It is better to organize work in such a way that the nature of the operations performed changes during the working day.

Radiation protection. One of the reasons for the deterioration of health among computer operators is the low quality of monitors.

Several years ago, to protect health, special screens were hung on monitors, which, however, did not always weaken the electromagnetic field. Thus, according to the Elite testing center, only two types of filters out of 200 used were certified, several of which were completely transparent to radiation.

When assessing the reliability of a filter, it is necessary to take into account the presence of three components of electromagnetic radiation:

1) electrostatic field, captured almost completely by the filters and removed from them by grounding the protective screen;

2) the electrical component of the electromagnetic field, not captured by filters, which only create an obstacle to its passage, as a result of which the flow goes around the filter and reconnects at a distance of 1.5-2 m from it;

3) magnetic component, practically not captured by filters (up to 5%).

An important measure for protection against radiation is the optimal placement of computers in the workroom (Fig. 10).

Personal protection factors. Personal protection factors are divided into three groups:

1) preventive medication measures;

2) improving the conditions for reading information;

3) shielding the operator entirely or individual areas of his body. The choice of personal protective factors depends on age, health status and length of work.

Preventive medication measures. Considering the fact that when working on a computer, mineral metabolism is disrupted, its normalization with the help of special drinks should be considered an important preventive measure. Preventive drinks are recommended for use by practically healthy adult operators when working no more than 8 hours a day. For example, Profile LLP developed a mineralized drink “Zashchita”, tested jointly with the State Sanitary and Epidemiological Supervision Service of Russia. The drink is produced by the research and production company Combiotech LTD. It is taken 50 ml every 3 - 4 hours of working with a computer.

Improving conditions for reading information. Preventive glasses with a special coating were developed by Lornet-M JSC and tested by the Moscow Research Institute of Eye Diseases named after. G.L. Helmholtz and the Institute of Biochemical Physics named after. acad. N. M. Emanuel. Glasses reduce eye fatigue by at least 25 - 30%. They are recommended for use by all operators when working at a computer for more than 2 hours a day, and if vision is impaired by two or more diopters - regardless of the duration of work.

Hygienic requirements to PC monitors and work organization. The premises should have mixed lighting (natural and artificial). Natural lighting in the room is provided through light openings. It is recommended that it be oriented to the north and northeast. The KEO value in areas with stable snow cover should be no lower than 1.2%, and in the rest of the territory - 1.5%.

The following requirements apply to the monitor:

a) its size must be at least 13 inches (~31 cm) diagonally;

b) it must have an anti-reflective coating;

c) jitter on the display should be within 0.1 mm. The image contrast must be at least 0.8. The duration of direct work with a computer depends on the availability of skills and the severity of the work and is:

For 1st grade schoolchildren - 10 minutes;

2-5th grades - 15 min;

6-7th grades - 20 min;

8-9th grades - 25 min;

10th - 11th grades with double classes: in the first lesson - 30 minutes, in the second - 20 minutes;

1st year students - 1 hour;

Senior students - 2 hours with a break of 15 - 20 minutes;

Teachers - 4 hours with a break of 15-20 minutes after 2 hours;

Computer operators - 6 hours with a break of 20 minutes every 2 hours.

Employees must undergo preliminary (upon hiring) and periodic medical examinations to prevent occupational diseases.

Occupational safety and health protection

Features of the monitor power supply. Opening the monitor by the user is unacceptable under any circumstances. This is not only life-threatening, but also technically useless, since there are no controls or adjustments inside the monitor that the user could use to improve its performance. Monitor parameters affect the organs of vision.

Essay

On the topic: Hygiene when working on a Personal Computer

Completed by: Sergeev N. Yu.

Student of group TM-11

Checked by: Abkarimova G. T.

Blagoveshchensk-2014

Safety and hygiene rules when working on a PC

Electrical safety requirements.

Personal computer electrical appliance. It differs from other electrical appliances in that it can be used for a long time without being disconnected from electrical network. In addition to the normal operating mode, the computer can be in an operating mode with reduced power consumption or in a standby mode waiting for a request. Due to the possibility of prolonged operation of the computer without disconnecting from the power supply, special attention should be paid to the quality of the power supply.

It is unacceptable to use low-quality and worn-out components in the power supply system, as well as their surrogate substitutes: sockets, extension cords, adapters, tees. It is unacceptable to independently modify sockets to accept plugs that meet other standards. Electrical contacts of sockets should not experience mechanical stress associated with connecting massive components (adapters, tees, etc.).
All power cables and wires should be located at the back of the computer and peripheral devices. Their placement in the user's work area is unacceptable.
Do not perform any operations related to connecting, disconnecting or moving components computer system without first turning off the power.
The computer should not be installed near electrical heaters or heating systems.
It is unacceptable to place foreign objects on the system unit, monitor and peripheral devices: books, sheets of paper, napkins, dust covers. This results in permanent or temporary blockage of the ventilation openings.
Do not introduce foreign objects into the service or ventilation openings of computer system components.

Features of the monitor power supply. The monitor has elements that can save high voltage for a long time after disconnecting from the network. Opening the monitor by the user is unacceptable under any circumstances. This is not only life-threatening, but also technically useless, since there are no organs inside the monitor that the user could adjust or configure to improve its performance. Opening and servicing of monitors can only be carried out in special workshops.

Features of the power supply of the system unit.

All components of the system unit receive electricity from the power supply. The PC power supply is a stand-alone unit located at the top of the system unit. Safety regulations do not prohibit opening the system unit, for example when installing additional internal devices or upgrading them, but this does not apply to the power supply. The computer power supply is a source of increased fire hazard, so it can only be opened and repaired in specialized workshops.

The power supply has a built-in fan and ventilation holes. In this regard, dust inevitably accumulates in it, which can cause short circuit. It is recommended to periodically (once or twice a year) use a vacuum cleaner to remove dust from the power supply through the ventilation holes without opening the system unit. It is especially important to perform this operation before each transportation or tilt of the system unit.

System of hygienic requirements.

Working with a computer for a long time can lead to health problems. Short-term work with a computer installed in gross violations of hygiene standards and rules leads to increased fatigue. The harmful effects of a computer system on the human body are complex. Monitor parameters affect the organs of vision. The equipment of the workplace affects the organs of the musculoskeletal system. The nature of the arrangement of equipment in a computer class and the mode of its use affects both the general psychophysiological state of the body and its visual organs.

Video system requirements.

In the past, monitors were viewed primarily as a source of harmful radiation, primarily affecting the eyes. Today this approach is considered insufficient. In addition to harmful electromagnetic radiation (which on modern monitors has been reduced to a relatively safe level), image quality parameters must be taken into account, and they are determined not only by the monitor, but also by the video adapter, that is, the entire video system as a whole.

Your computer monitor must meet the following international safety standards:
- according to the level of electromagnetic radiation TSO 95;
- according to image quality parameters (brightness, contrast, flicker, anti-glare properties, etc.) TCO 99.

Find out about compliance specific model These standards can be found in the accompanying documentation. To work with monitors that meet these standards, special protective screens are not required.

At the workplace, the monitor must be installed in such a way as to exclude the possibility of reflection from its screen towards the user from sources of general lighting in the room.
The distance from the monitor screen to the user’s eyes should be from 50 to 70 cm. There is no need to try to move the monitor as far as possible from the eyes for fear of harmful radiation (based on everyday experience with TV), because the viewing angle of the most characteristic objects is also important for the eye. Optimally, the monitor is placed at a distance of 1.5 D from the user’s eyes, where D is the size of the monitor screen, measured diagonally. Compare this recommendation with the 3...5 D value recommended for household televisions, and compare the size of the characters on the monitor screen (the most typical object that requires concentration) with the size of objects typical for television (images of people, buildings, natural objects). An excessive distance from the eyes to the monitor leads to additional stress organs of vision, affects the difficulty of transition from working with a monitor to working with a book and manifests itself in the premature development of farsightedness.
An important parameter is the frame rate, which depends on the properties of the monitor, video adapter and software settings of the video system. To work with texts, the minimum frame rate allowed is 72 Hz. For graphics work, a frame rate of 85 Hz or higher is recommended.

Workplace requirements.

The requirements for the workplace include requirements for a desktop, a seat (chair, armchair), rests for arms and legs. Despite its apparent simplicity, ensuring the correct placement of computer system elements and the correct seating of the user is extremely difficult. A complete solution to the problem requires additional costs comparable in magnitude to the cost of individual components of a computer system, therefore, both in production and in production, these requirements are often neglected.
Despite the fact that schoolchildren spend relatively little time in the computer classroom, teaching them proper occupational hygiene through a worthy example is very important so that useful skills are reinforced for life. This is not just a requirement of hygiene, but a requirement of methodology.

The monitor should be installed directly in front of the user and should not require rotation of the head or body.

The desktop and seat should be of such a height that the user's eye level is slightly above the center of the monitor. You should look at the monitor screen from top to bottom, and not vice versa. Even short-term work with a monitor installed too high leads to fatigue of the cervical spine.

If at correct installation monitor relative to eye level, it turns out that the user’s feet cannot rest freely on the floor, a footrest should be installed, preferably inclined. If the legs do not have reliable support, this will certainly lead to poor posture and fatigue of the spine. It is convenient when computer furniture (desk and work chair) have means for height adjustment. In this case, it is easier to achieve the optimal position.
The keyboard should be located at such a height that the fingers rest on it freely, without tension, and the angle between the shoulder and forearm is 100° 110°. When using ordinary school desks, it is almost impossible to achieve the correct position of both the monitor and the keyboard at the same time. For work, it is recommended to use special computer tables that have pull-out shelves for the keyboard. If there is no such shelf and the keyboard is located on the same table as the monitor, the use of a footrest becomes almost inevitable, especially when children work with the computer.

Working with the keyboard for a long time can cause fatigue in the tendons of the wrist joint. A known serious occupational disease is carpal tunnel syndrome, which is associated with incorrect hand position on the keyboard. To avoid excessive stress on the hand, it is advisable to provide a work chair with armrests, the height of which, measured from the floor, coincides with the height of the keyboard.
When working with the mouse, your hand should not be suspended. The elbow or at least the wrist should have firm support. If it is difficult to provide the necessary location of the desktop and chair, it is recommended to use a mouse pad with a special support roller. There are often cases when, in search of support for the hand (usually the right one), the monitor is placed on the side of the user (respectively, on the left) so that it works half-turned, resting on the elbow or wrist right hand about the table. This technique is unacceptable. The monitor must be directly in front of the user.

Requirements for organizing classes.

The monitor screen is not the only source of harmful electromagnetic radiation. Monitor developers have been successfully overcoming them for a long time. Less attention is paid to harmful spurious emissions arising from the sides and rear walls of equipment. In modern computer systems, these areas are the most dangerous.
The computer monitor should be positioned so that its back wall faces the wall of the room rather than people. In computer classes with several computers, workstations should be located along the periphery of the room, leaving the center free. In this case, it is additionally necessary to check each of the workplaces for the absence of direct reflection of external lighting sources. As a rule, it is quite difficult to achieve this for all jobs at the same time. Possible Solution consists of using curtains on the windows and thoughtful placement of artificial sources of general and local lighting.
Devices are strong sources of electromagnetic radiation uninterruptible power supply. They should be located as far as possible from user seats.

In organizing classes, their duration plays an important role, on which psychophysiological loads depend. For high school students, the duration of a computer session should not exceed 30 minutes, for elementary school students - 20 minutes. The rest of the computer science lesson is spent communicating with the teacher and teaching aids.
Due to a lack of equipment, computer classes sometimes conduct group classes, during which two or three students study at one workstation. This organizational technique is unacceptable from a hygienic point of view. Some students have to sit to the side of the monitor, which negatively affects both the visual organs and the musculoskeletal system. The educational process must be planned so that every student has the opportunity to learn the correct techniques for working with a computer.

Electrical safety requirements

A personal computer is an electrical device. It differs from other electrical appliances in that it can be used for a long time without being disconnected from the electrical network. In addition to the normal operating mode, the computer can be in an operating mode with reduced power consumption or in a standby mode waiting for a request. Due to the possibility of prolonged operation of the computer without disconnecting from the power supply, special attention should be paid to the quality of the power supply.

1. It is unacceptable to use low-quality and worn-out components in the power supply system, as well as their surrogate substitutes: sockets, extension cords, adapters, tees. It is unacceptable to independently modify sockets to accept plugs that meet other standards. Electrical contacts of sockets should not experience mechanical stress associated with connecting massive components (adapters, tees, etc.).

2. All power cables and wires should be located at the back of the computer and peripheral devices. Their placement in the user's work area is unacceptable.

3. It is prohibited to perform any operations related to connecting, disconnecting or moving components of a computer system without first turning off the power.

4. The computer should not be installed near electric heaters or heating systems.

5. It is unacceptable to place foreign objects on the system unit, monitor and peripheral devices: books, sheets of paper, napkins, covers to protect against dust. This results in permanent or temporary blockage of the ventilation openings.

6. It is prohibited to introduce foreign objects into the service or ventilation openings of computer system components.

Features of the monitor power supply. The monitor has elements that can maintain high voltage for a long time after being disconnected from the network. Opening the monitor by the user is unacceptable under any circumstances. This is not only life-threatening, but also technically useless, since there are no organs inside the monitor that the user could adjust or configure to improve its performance. Opening and servicing of monitors can only be carried out in special workshops.

Features of the power supply of the system unit

All components of the system unit receive electricity from the power supply. The PC power supply is a stand-alone unit located at the top of the system unit. Safety regulations do not prohibit opening the system unit, for example, when installing additional internal devices or upgrading them, but this does not apply to the power supply. The computer power supply is a source of increased fire hazard, so it can only be opened and repaired in specialized workshops.

The power supply has a built-in fan and ventilation holes. Due to this, dust will inevitably accumulate in it, which can cause a short circuit. It is recommended to periodically (once or twice a year) use a vacuum cleaner to remove dust from the power supply through the ventilation holes without opening the system unit. It is especially important to perform this operation before each transportation or tilt of the system unit.

System of hygienic requirements.

Video system requirements.

1. The computer monitor must meet the following international safety standards:

o according to the level of electromagnetic radiation - TSO 95;

o in terms of image quality parameters (brightness, contrast, flicker, anti-glare properties, etc.) - TCO 99.

You can find out about the compliance of a specific model with these standards in the accompanying documentation. To work with monitors that meet these standards, special protective screens are not required.

2. At the workplace, the monitor must be installed in such a way as to exclude the possibility of reflection from its screen towards the user from sources of general lighting in the room.

3. The distance from the monitor screen to the user’s eyes should be from 50 to 70 cm. There is no need to try to move the monitor as far as possible from the eyes for fear of harmful radiation (based on everyday experience with TV), because the viewing angle of the most characteristic features is also important for the eye. objects. Optimally, the monitor should be placed at a distance of 1.5 D from the user's eyes, where D is the size of the monitor screen, measured diagonally. Compare this recommendation with the 3...5 D value recommended for household televisions, and compare the size of the characters on the monitor screen (the most typical object that requires concentration) with the size of objects typical for television (images of people, buildings, natural objects). An excessive distance from the eyes to the monitor leads to additional strain on the visual organs, affects the difficulty of transition from working with a monitor to working with a book, and manifests itself in the premature development of farsightedness.

4. An important parameter is the frame rate, which depends on the properties of the monitor, video adapter and software settings of the video system. To work with texts, the minimum frame rate allowed is 72 Hz. For graphics work, a frame rate of 85 Hz or higher is recommended.

Workplace requirements.

Despite the fact that schoolchildren spend relatively little time in the computer classroom, teaching them proper occupational hygiene through a worthy example is very important so that useful skills are reinforced for life. This is not just a requirement of hygiene, but a requirement of methodology.

1. The monitor should be installed directly in front of the user and should not require rotation of the head or body.

Figure 3. Correct monitor placement

2. The desktop and seat should be of such a height that the user's eye level is slightly above the center of the monitor. You should look at the monitor screen from top to bottom, and not vice versa. Even short-term work with a monitor installed too high leads to fatigue of the cervical spine.

Figure 4. Correct monitor placement

3. If, when correctly installing the monitor relative to eye level, it turns out that the user’s feet cannot rest freely on the floor, a footrest should be installed, preferably an inclined one. If the legs do not have reliable support, this will certainly lead to poor posture and fatigue of the spine. It is convenient when computer furniture (desk and work chair) have means for height adjustment. In this case, it is easier to achieve the optimal position.

4. The keyboard should be located at such a height that the fingers rest on it freely, without tension, and the angle between the shoulder and forearm is 100° - 110°. When using ordinary school desks, it is almost impossible to achieve the correct position of both the monitor and the keyboard at the same time. For work, it is recommended to use special computer tables that have pull-out shelves for the keyboard. If there is no such shelf and the keyboard is located on the same table as the monitor, the use of a footrest becomes almost inevitable, especially when children work with the computer.

Figure 5. Workplace organization

5. Working with the keyboard for a long time can cause fatigue in the tendons of the wrist joint. A serious occupational disease is known - carpal tunnel syndrome, associated with incorrect hand position on the keyboard. To avoid excessive stress on the hand, it is advisable to provide a work chair with armrests, the height of which, measured from the floor, coincides with the height of the keyboard.

6. When working with the mouse, your hand should not be suspended. The elbow or at least the wrist should have firm support. If it is difficult to provide the necessary location of the desktop and chair, it is recommended to use a mouse pad with a special support roller. There are often cases when, in search of support for the hand (usually the right one), the monitor is placed on the side of the user (respectively, on the left) so that he works half-turned, resting the elbow or wrist of the right hand on the table. This technique is unacceptable. The monitor must be directly in front of the user.