The severity and intensity of work characterized by the degree of functional stress of the body. It can be energetic, depending on the power of work - during physical labor, and emotional - during mental labor. Thus, the severity of labor is a quantitative characteristic of physical labor. Labor intensity is a quantitative characteristic of mental labor. It is determined by the amount of information load.

By indicators of the severity and intensity of labor There are three classes of working conditions:

optimal (light) - energy costs up to 174 W;

permissible (moderate) - energy costs from 175 to 290 W;

harmful (heavy) - energy costs over 290 watts.

Based on a comprehensive quantitative assessment of working conditions factors, called integral value the severity and intensity of labor is carried out medical-physiological classification the severity and intensity of labor, according to which 6 categories of work are distinguished. Categories of work are delimited on the basis of the intensity of the body's energy expenditure in kcal / h (W).

Category Ia include work with an intensity of energy consumption up to 120 kcal / h (up to 139 W), performed while sitting and accompanied by slight physical stress (a number of professions in precision instrumentation and engineering enterprises, in watchmaking, clothing production, in management, etc.).

Category Ib include work with an intensity of energy consumption of 121 - 150 kcal / h (140 - 174 W), performed while sitting, standing or walking and accompanied by some physical stress (a number of professions in the printing industry, in communications enterprises, controllers, craftsmen in various types of production and etc.).

Category IIa include work with an intensity of energy consumption of 151 - 200 kcal / h (175 - 232 W), associated with constant walking, moving small (up to 1 kg) products or objects in a standing or sitting position and requiring a certain physical exertion (a number of professions in mechanical assembly shops engineering enterprises, in spinning and weaving, etc.).

Category IIb include work with an energy consumption intensity of 201 - 250 kcal / h (233 - 290 W), associated with walking, moving and carrying loads up to 10 kg and accompanied by moderate physical stress (a number of professions in mechanized foundry, rolling, forging, thermal, welding machine-building shops And metallurgical enterprises and so on.).

Category III include work with an energy intensity of more than 250 kcal / h (more than 290 W), associated with constant movement, moving and carrying significant (over 10 kg) weights and requiring great physical effort (a number of professions in blacksmith shops with manual forging, foundries with manual stuffing and casting molding boxes of machine-building and metallurgical enterprises, etc.).

The physical burden of labor - this is a load on the body during labor, requiring mainly muscle effort and appropriate energy supply. The classification of physical labor according to severity is made according to the level of energy consumption, taking into account the type of load (static or dynamic) and the muscles being loaded. Physical work is divided into two types: dynamic and static.

Dynamic work - the process of muscle contraction, leading to the movement of the load, as well as the human body itself or its parts in space. In this case, energy is spent both on maintaining a certain tension in the muscles, and on the mechanical effect of work.

Dynamic physical work, in which more than 2/3 human muscle is called general, with participation in work from 2/3 to 1/3 human muscles (muscles only of the body, legs, arms) - regional, less than 1/3 of the muscles - local (for example, typing on a computer).

Dynamic load indicators:

the mass of the lifted and moved cargo manually;

distance of cargo movement;

the power of the work performed: when working with the muscles of the lower extremities and trunk, with the predominant participation of the muscles of the shoulder girdle;

small, stereotyped movements of the hands and fingers, number per shift;

movement in space (transitions due to technological process), km.

The physical burden of work is determined by energy costs in the process of labor activity and is divided into the following categories: light, moderate and heavy physical work.

Medium physical work (category II) is divided into two categories:

Category IIa, at which the energy costs are 175-232 Tue , (includes work associated with constant walking, moving small (up to 1 kg) products or objects in a standing or sitting position and requiring certain physical effort);

Category IIb, at which energy consumption is 233-290 W (works related to walking, moving and carrying loads weighing up to 10 kg and accompanied by moderate physical effort include);

Heavy physical work (category III) are characterized by energy consumption of more than 290 W (they include work associated with constant movement, movement and transfer of significant (over 10 kg) weights and requiring great physical effort).

Dynamic physical load is determined, as a rule, by one of the following indicators: 1) work (kg?m); 2) power of effort (W); static physical load is determined in kg / s.

associated with the expenditure of human effort on the muscles without moving the body or its individual parts. The magnitude of the static load is determined by the product of the magnitude of the effort by the maintenance time (in the case of different magnitudes of efforts, the maintenance time of each of them is determined separately, the products of the magnitude of the effort by the maintenance time are found, and then these products are summed up).

At static load assessment the group of muscles involved in the work is also taken into account. So, with light physical activity (the optimal class of working conditions), the value of the static load per shift when holding the load with both hands should not exceed 36,000 kg?s, while holding the load with the participation of the muscles of the body and legs - 43,000 kg / s, and when gravity - respectively, 70,000 kg/s and 100,000 kg/s.

Static load indicators:

weight of the retained cargo, kg;

duration of holding the load, s;

static load per shift, N, when holding the load: with one hand, with two hands, with the participation of the muscles of the body and legs;

working posture, being in an inclined position, the percentage of shift time;

forced tilts of the body more than 30°, quantity per shift; - linear spatial layout parameter of the elements production equipment and workplace, mm;

angular spatial and layout parameter of the elements of production equipment and workplace, viewing angle;

the value of the resistance of the drive elements of the controls (the force required to move the controls), N.

In addition to the static, dynamic load and the mass of the lifted and moved cargo, the assessment of working conditions according to the severity of the labor process is carried out by working posture ,number of slopes per shift ,the number of stereotyped working movements and movement in space due to the technological process.

So, with repetitive (stereotypical) working movements of the muscles of the hands and fingers up to 20,000 times per shift, working conditions are considered optimal. Over 20,000 to 40,000 - admissible. If the number of movements reaches 60,000, then the working conditions include to harmful 1st degree .

Under the movement in space understand the transitions during the shift, due to the technological process. Walking up to 4 km - optimal working conditions; from 4 to 8 - admissible , and up to 12 and more - respectively harmful working conditions of the 1st and 2nd degrees.

Labor intensity It is characterized by an emotional burden on the body during work, which requires mainly the work of the brain to receive and process information.

When assessing the intensity of mental labor, indicators of attention, the intensity of visual work and hearing, and the monotony of labor are used.

• 1) Most easy with read mental work, in which there is no need to make a decision. These working conditions are considered optimal. If the operator works and makes decisions within the framework of one instruction, then such working conditions include Toadmissible. To tense harmful conditions of the 1st degree include labor that is associated with the decision challenging tasks according to known algorithms or work using several (more than one) instructions. Creative activity that requires solving complex problems in the absence of an obvious solution algorithm should be classified as hard work of the 2nd degree of severity .
• 2) Processing any information or performing a task without evaluating its results is not difficult work, which allows it to be evaluated as optimal . If the need to verify the result obtained is added to these actions, then such working conditions are admissible. The work of distributing the production task among other persons and monitoring their work includes to hard work of the 2nd degree .

The intensity of work depends on duration of focused observation And number of simultaneously observed objects (instruments, product of production, etc.).

• 3) With the duration of concentrated observation up to 25% of the duration of the work shift, working conditions are characterized as optimal, 26-50 -admissible , 51-75 -hard work 1st degree , more than 75 - 2nd degree.
• 4) With the number of objects up to 5 inclusive, working conditions refer to optimal class , from 6 to 10 - valid class , more than 10-conditions are defined as tense . TO first degree hard work relate production processes with the number of objects under control from 11 to 25, and to the second - 26 and more.
• 5) Work with video display terminals up to 2 hours per shift is considered optimal , up to 3 h - admissible . Working at a computer or monitoring the process on a video terminal for more than 3 hours defines the class of working conditions as tense : 3 to 4 hours - first degree , more than 4 h - second degree .

Significant influence on the degree of stress state of the performer has responsibility for the final or intermediate result labor.

• 6) If the operator is responsible for the performance of only certain elements of the production task, then such work is evaluated as optimal. Increasing the degree of responsibility, for example, for the functional quality of auxiliary operations entails additional emotional efforts on the part of the immediate supervisor (foreman, foreman, etc.). In these cases, labor is valued as valid. If the performer is responsible for the functional quality of the main work, which may lead to the need to make decisions related to the correction (alteration) of the results due to the additional efforts of the entire team, then this type of activity is tense 1st degree . If the employee is personally responsible for the functional quality of the final product, the production task as a whole, or his actions can lead to equipment breakdown, stop the entire technological process or create a life-threatening situation, his working conditions are assessed as strained 2nd degree .
• 7) In the absence of a risk to one's own life in the course of performing one's duties, the work of the performer is considered optimal , if it is probable, then the working conditions are attributed to hard work of the 2nd degree . Similarly, a class of working conditions is established when assessing the degree of risk for the safety of other persons participating in the production process.

The monotony of the operations performed leads a person to a state called monotomy.

A sign of monotomy is either an overload of the same information or a lack of new information. The degree of monotony is determined by the number of elements (methods of labor in the implementation of a simple task or repeatedly repeated operations) and the duration in time of these elements or operations.

8) If the number of elements is 10 or more, then the working conditions are considered optimal ; 6-9 -admissible , less than 6 - tense .

Important factors characterizing the class of working conditions according to the intensity of the labor process are actual working hours and shifts.

With a working day of up to 7 hours, working conditions are classified as optimal class, until 9 a.m. admissible , more than 9 h - to tense. One-shift work without night shift - optimal conditions; two-shift work without night shift work - admissible working conditions and three-shift work with night shift work - hard work 1st degree .

The severity of labor- a characteristic of the labor process, reflecting the predominant load on the musculoskeletal system and functional systems organism ( cardiovascular, respiratory, etc.) to ensure its operation.

As part of the certification of workplaces, we are interested in what kind of dynamic, static work the employee performed, how much he lifted, moved, twisted, walked, how many times he bent over.

Impact on the human body

Physical labor is characterized by a heavy load on the body, requiring mainly muscle effort and appropriate energy supply, and also affects functional systems (cardiovascular, neuromuscular, respiratory, etc.), stimulates metabolic processes. Its main indicator is severity. Energy consumption during physical labor, depending on the severity of the work, is 4000 - 6000 kcal per day, and with a mechanized form of labor, energy costs are 3000 - 4000 kcal.

With very hard work, oxygen consumption continuously increases, and oxygen debt can occur when non-oxidized metabolic products accumulate in the body. The growth of metabolism and energy consumption leads to an increase in heat generation, body temperature by 1 - 1.5 ° C. Muscular work affects the cardiovascular system, increasing blood flow from 3 - 5 l / min to 20 - 40 l / min to ensure gas exchange. At the same time, the number of heart contractions increases to 140 - 180 per minute. and blood pressure up to 180 - 200 mm Hg.

Under the influence of muscular work, the morphological composition of the blood, its physicochemical properties change: the number of erythrocytes and hemoglobin content increase, the process of erythrocyte regeneration intensifies, and the number of leukocytes increases. These changes indicate an increase in the function of the hematopoietic organs. Certain changes during physical work occur in endocrine functions (increased levels of adrenaline in the blood, etc.), which contributes to the mobilization energy resources organism.

Normalized indicators

The assessment of the severity of labor is carried out according to 7 main indicators:

the mass of the lifted and moved cargo manually;

stereotyped labor movements;

working posture;

body slopes;

movement in space.

The severity of labor must be assessed at each workplace. When assessing the severity of labor, all of the above indicators are evaluated. Based on the characteristics of the labor process, it is concluded that it is necessary to fulfill each of the indicators of the severity of labor in connection with the technological process. If it is characteristic, its quantitative or qualitative assessment to establish a class of working conditions. If the indicator is not used in the course of the labor process, when drawing up a protocol for unused indicators, a dash is put in the column for the actual value, and 1 in the assessment class.

Evaluation of the severity of labor is carried out based on the work shift (8 hours). Evaluation is not carried out for individual operations that the employee performs in accordance with his job description and throughout the entire shift. When performing work associated with uneven physical activity in different shifts, an assessment of the indicators of the severity of the labor process (with the exception of the mass of the lifted and moved load and the inclination of the body) should be carried out according to average indicators for 2-3 days in terms of one work shift.

Classes of working conditions in terms of the severity of the labor process

Indicators of the severity of the labor process	Optimal class of working conditions	Permissible class of working conditions	Harmful class 3.1	Harmful class 3.2
1.Physical dynamic
1.1. With a regional load (with the predominant participation of the muscles of the arms and shoulder girdle) when moving the load at a distance of up to 1 m:
for men	up to 2500	up to 5000	up to 7000	over 7000
for women	up to 1500	up to 3000	up to 4000	over 4000
1.2. With a general load (with the participation of the muscles of the arms, body, legs):
1.2.1. When moving a load over a distance of 1 to 5 m
for men	up to 12500	up to 25000	up to 35000	over 35000
for women	up to 7500	up to 15000	up to 25000	over 25000
1.2.2. When moving a load over a distance of more than 5 m
for men	up to 24000	up to 46000	up to 70000	over 70000
for women	up to 14000	up to 28000	up to 40000	over 40000
2. Mass of lifted and moved cargo manually (kg)
2.1. Lifting and moving (one-time) gravity when alternating with other work (up to 2 times per hour):
for men	up to 15	up to 30	up to 35	over 35
for women	up to 5	to 10	up to 12	over 12
2.2. Lifting and moving (one-time) gravity constantly during the work shift:
for men	up to 5	up to 15	up to 20	over 20
for women	until 3	up to 7	to 10	over 10
2.3. The total mass of goods moved during each hour of the shift:
2.3.1. From work surface
for men	up to 250	up to 870	up to 1500	over 1500
for women	up to 100	up to 350	up to 700	over 700
2.3.2. off the floor
for men	up to 100	up to 435	up to 600	over 600
for women	up to 50	up to 175	up to 350	over 350
3. Stereotypical work movements (number per shift)
3.1. With local load (involving the muscles of the hands and fingers)	up to 20000	up to 40000	up to 60000	over 60000
3.2. With a regional load (when working with the predominant participation of the muscles of the arms and shoulder girdle)	up to 10000	up to 20000	up to 30000	over 30000
4. Static load - the value of the static load per shift when holding the load, applying efforts (kgf s)
4.1. With one hand:
for men	up to 18000	up to 36000	up to 70000	over 70000
for women	up to 11000	up to 22000	up to 42000	over 42000
4.2. Two hands:
for men	up to 36000	up to 70000	up to 140000	over 140000
for women	up to 22000	up to 42000	up to 84000	over 84000
4.3. With the participation of the muscles of the body and legs:
for men	up to 43000	up to 100000	up to 200000	over 200000
for women	up to 26000	up to 60000	up to 120000	over 120000
5. Working posture
5. Working posture	Free, comfortable posture, the ability to change the working position of the body (sitting, standing). Staying in a standing position up to 40% of the shift time.	Periodic, up to 25% of the shift time, being in an uncomfortable (work with rotation of the body, awkward placement of limbs, etc.) and / or fixed position (impossibility to change the relative position of different parts of the body relative to each other). Staying in a standing position up to 60% of the shift time.	Periodic, up to 50% of the shift time, being in an uncomfortable and / or fixed position; stay in a forced position (kneeling, squatting, etc.) up to 25% of the shift time. Standing up to 80% of shift time	Periodic, more than 50% of the shift time, being in an uncomfortable and / or fixed position; stay in a forced position (kneeling, squatting, etc.) for more than 25% of the shift time. Staying in a standing position for more than 80% of the shift time.
6. Body slopes
Hull tilts (forced over 30°), number per shift	up to 50	51-100	101-300	over 300
7. Movements in space due to the technological process, km
7.1. Horizontally	up to 4	up to 8	up to 12	over 12
7.2. Vertically	up to 1	up to 2.5	up to 5	over 5

(expressed in units of external mechanical work per shift - kg * m). It is estimated as the product of the mass of the load (parts, products, tools, etc.) by the distance of its movement. To do this, the workplace records the number of repetitions, the mass of parts and the distance that the worker moved the parts. That is, it is nothing more than the sum of the products of the weight of the parts and the distance they were moved. Moreover, the average distance over which the worker moves the load is calculated by adding the distance of all movements and dividing them by the number of movements.

The standards for this indicator are very high. It is very difficult to fulfill the norm set even for an acceptable class of working conditions. Let's look at a few examples.

Example 1 . At regional load (with the predominant participation of the muscles of the arms and shoulder girdle) when moving a load over a distance of up to 1 m, the allowable load for men is 5000 kg. m. (Grade 2).

For example, let's make a calculation for moving a load of 30 kg per 1 meter 2 times per hour.

Accordingly, for an 8-hour shift, the employee moves the load 16 times:

16 times x 30 kg x 1 m = 480 kg*m

5000 kg*m / 30 kg / 1 m = 166 times

Thus, for an 8-hour shift, the worker moves the load every 3 minutes.

480 min / 166 times = 2.9 min = 3 min

Example 2 . When moving a load over a distance of 5 m, the norm for acceptable class 2 for men is 25,000 kg * m (clause 1.2.1). Let's calculate for an 8-hour shift:

30 kg x 2 times per hour. 5 m. = 300 kg. m x 8 h = 2400 kg. m.

If we calculate from the reverse, we get:

25000 kg. m. / 30 kg / 5 m = 166 times.

Thus, for an 8-hour shift, the worker moves the load by 5 m every 3 minutes.

2. The mass of the lifted and moved cargo manually(kg)

It is estimated by the maximum weight of the load lifted and moved by the employee for a single action and by the total weight of the goods moved during each hour of the shift. There are two indicators that estimate the maximum mass of a load lifted or moved by an employee at a time:

• lifting and moving (one-time) gravity when alternating with other work (up to 2 times per hour);
• lifting and moving (one-time) gravity constantly during the work shift.

The mass of the load lifted and moved manually should be estimated at the maximum values.

Total weight of cargo moved during each shift hour is valued as:

• total mass of cargo moved from the working surface per shift hour or as
• the total mass of cargo moved from the floor per shift hour.

The working surface is a surface that is 0.5 meters above the level of the floor on which the worker stands. Everything else is floor. It is calculated as the total weight of the load moved by the worker during the shift, divided by the shift time (in hours). For example, if a loader carries 400 kg per shift, then in an hour it will be 400 / 8 = 50 kg.

The choice of evaluation criterion is carried out according to the predominant movement (from the floor or work surface). If the employee during the shift moves the load both from the floor and from the working surface, then the indicators are summarized. If a larger load was moved from the working surface than from the floor, then we compare the obtained value with the indicator when moving from the working surface, if vice versa, then with the indicator when moving from the floor. If an equal load is moved from the working surface and from the floor, then the total mass of the load is evaluated with the indicator of movement from the floor.

The total mass of goods moved during each hour of the shift from the working surface for men is up to 870 kg (clause 2.3.1).

Thus, to achieve this norm, a worker will move a load of 30 kg 29 times per hour, every 2 minutes.

870 kg / 30 kg = 29 times (every 2 minutes)

If we make a calculation for a load of 15 kg, we get:

870 kg / 15 kg = 58 times (every min)

Is it possible to work at this pace every day? The standards are also very high.

3. Stereotypical labor movements(number per shift)

Stereotypical working movements are elementary, repetitive movements in which the same muscle groups are involved. According to the amplitude of movements, stereotyped movements are divided into local and regional. If the amplitude is small (it usually happens when only the muscles of the fingers and hands are involved), then these are local stereotyped movements.

If the amplitude of movements is greater, and the muscles of the forearm, shoulder, etc. are involved, then these are already regional stereotypical movements.

The calculation is simple. Since the movement is repeated many times, then we count the movements for 5-10 minutes for one operation, and then multiply by the time of this operation or by the entire shift. If there are several operations, then we count the number of movements for each operation, and then summarize.

Let us give examples showing how much the standards are overestimated.

1. With a local load (with the participation of the muscles of the hands and fingers), the norm for an acceptable class of working conditions is up to 40,000 movements per shift (clause 3.1). Every second, the worker will make 1.4 movements.

40,000 movements / 3600 sec / 8h = 1.4 movements per second

2. In the same way, you can evaluate the regional load (when working with the predominant participation of the muscles of the arms and shoulder girdle) (paragraph 3.2). The norm for an acceptable class of working conditions is up to 20,000 movements per shift. Let's do the calculation in a similar way.

20,000 movements / 3600 sec / 8 hours = 0.7 movements per second.

- the value of the static load per shift when holding the load, applying efforts (kgf * s).

Rated as:

• the value of the static load per shift when holding the load with one hand;
• the value of the static load per shift when holding the load with both hands;
• the value of the static load per shift when holding the load with the participation of the muscles of the body and legs.

The static load associated with a person holding a load or applying force without moving the body is calculated by multiplying two parameters: the magnitude of the force held and the time it is held.

Under production conditions, static forces occur in two forms: holding the workpiece (tool) and pressing the workpiece (workpiece) to the workpiece (tool). In the first case, the value of the static force is determined by the weight of the product (tool) being held. The weight of the product is determined by weighing on the scales, i.e. The weight of a load is its mass. In the second case, the value of the pressing force can be determined using sensors that must be fixed on the tool or product. The static force time is determined on the basis of chronometric measurements.

Consider an example.

When holding the load with one hand, the norm for the permissible class of working conditions for men is up to 36,000 kgf.s (clause 4.1). Let's make a calculation to hold a load of 10 kg.

36,000 kgf * s / 10 kg \u003d 3600 s \u003d 1 hour

That is, the employee in total for an 8-hour work shift holds the load with one hand for 1 hour or 7.5 min / hour.

When holding the load with two hands, the norm for the permissible class of working conditions for men is up to 70,000 kgf * s (clause 4.2). Let's make a calculation to hold a load of 20 kg.

70,000 kgf.s / 20kg = 3500 s = 1 hour When holding a load with one hand, the norm for an acceptable class of working conditions for women is up to 22,000 kgf.s (clause 4.1). Let's make a calculation to hold a load of 7 kg.

22,000 kgf * s / 7 kg \u003d 3142 s \u003d 50 min.

5. working posture

The nature of the working posture (free, uncomfortable, fixed, forced) is determined visually. The time spent in a forced position, a position with a tilt of the body or another working position is determined on the basis of timing data for the shift, or by monitoring the progress of the labor process and interviewing employees.

Particular attention in assessing the severity of labor should be paid to the assessment of the working posture. For example, machine operators of various specialties, locksmiths, electricians, conveyor line workers, security guards, etc. work for a long time in a standing position. Uncomfortable posture, in which the worker must make efforts to hold certain parts of the body (in an inclined position of the body up to 300, with a turn of the torso, with arms raised above shoulder level, with an uncomfortable position of the limbs), is typical for car repairmen when they are in inspection ditches , electricians of the contact network, etc. A fixed posture is characteristic of professions performing work using optical instruments, during welding, seamstresses, computer operators when typing, cashiers, crane operators, drivers, many work on the conveyor, etc. Free postures include comfortable “sitting” or “sitting-standing” postures, when the employee can, at his own discretion, at any time change the position of the body or its individual parts ( lean back in a chair, change the position of the arms and legs ), get up. Free poses include administrative and management personnel, office workers, dispatchers, etc._

The choice of posture for evaluation should be made depending on the time spent in it. It is necessary to take as a basis the position in which the employee spends most of the time during the shift, i.e. the most typical.

6. Hull slopes(number per shift). The number of slopes per shift is determined by directly counting them or by determining their number in one operation and multiplying by the number of operations per shift. An inclination of more than 30 degrees means that the person leans to a surface that is no more than 50 cm from the floor.

The norm for an acceptable class of working conditions is 51 - 100 slopes per shift.

Let's calculate: 480 min / 100 slopes = 4.8 min.

In order to achieve this norm of 100 slopes, the employee will need to perform slopes every 5 minutes during an 8-hour work shift.

7. Moving in space(transitions due to the technological process during the shift horizontally or vertically - along stairs, ramps, etc., km).

The easiest way to determine this value is to use a pedometer, which can be placed in a worker's pocket or fastened to his belt, to determine the number of steps per shift (during regulated breaks and lunch breaks, remove the pedometer). Multiply the number of steps per shift by the length of the step (male step in a production environment on average = 0.6 m, and female = 0.5 m), and express the resulting value in km. Vertical movement can be considered movement on stairs or inclined surfaces, the angle of inclination of which is more than 30 ° from the horizontal.

Horizontally : On average, a person moves 4 km per hour. The norm for an acceptable class of working conditions is 8 km (clause 7.1). Accordingly, an employee will walk at least 2 hours per shift per day.

Vertically : If we consider a typical building with 9 floors (330 / 9 = 37), then to fulfill the standard corresponding to class 1, you need to climb 9 floors 37 times per shift.

General assessment of the severity of the labor process

The assessment of the severity of physical labor is carried out on the basis of taking into account all those given in Table. 17 indicators. At the same time, a class is first set for each measured indicator, and the final assessment of the severity of labor is set for the most sensitive indicator that received the highest degree of severity. If there are two or more indicators of class 3.1 and 3.2, working conditions are rated one degree higher in terms of the severity of the labor process (classes 3.2 and 3.3, respectively). According to this criterion, the highest severity level is class 3.3.

Methodology for assessing the severity of the labor process

The methodology for assessing labor intensity is carried out in accordance with the "Guidelines for hygiene assessment factors of the working environment and the labor process. Criteria and classification of working conditions» R 2.2.2006-05 Appendix 15. Each of the listed indicators can be quantitatively measured and evaluated in accordance with Guidelines R 2.2.2006-05. Expert evaluation is carried out by observing and fixing the most characteristic operations. Then quantitative measurements are carried out. The main thing is to calculate correctly.

Measuring instruments

The main means for measuring the severity of the labor process are a stopwatch, a dynamometer, a pedometer, a laser ruler.

Events

Reduction of physical stress among workers, increase in safety and labor efficiency can be implemented by implementing the following measures (see below).

Mechanization of work . When implementing this measure, it is necessary to pay attention to the main indicators of complex mechanization and patterns that characterize the effectiveness of mechanization means, the methodology and procedure for choosing machines for leading and non-leading operations; determine the schemes for organizing technological processes, guided by organizational and technological documentation: technological maps and calculations, maps of labor processes, schemes for operational quality control of work, standard sets for work, calculation of labor costs.

Acquisition and timely repair of small-scale mechanization. Means of small-scale mechanization include fixtures, working tools, equipment, machines and mechanisms for the mechanization of auxiliary and low-volume construction and installation works.

Implementation in production activities the most expedient mode of work and rest (a rational system of alternating periods of work and breaks between them).

In addition to regulated breaks, micropauses- breaks lasting from a few seconds to 1 minute. Micropauses are obligatory in any labor process, for example, in the form of pauses for organs or muscles (short-term pauses for restructuring the processes of excitation and inhibition of individual functional systems or organs without a general interruption of the labor process).

Industrial gymnastics. It is a preventive measure for the normalization of muscle fatigue, as well as the functions of blood circulation and respiration. Industrial gymnastics is based on the phenomenon of active rest - tired muscles quickly restore their working capacity not at complete rest, but at the work of other muscle groups. As a result of industrial gymnastics, the vital capacity of the lungs increases, the activity of the cardiovascular system improves, and functionality analyzer systems, increases muscle strength and endurance.

The basic principle of classifying types of labor is physiological criteria. The physiological classification of labor activity with significant muscle activity is based on energy consumption. Light physical work -- 1st category A And b performed sitting or standing, or with a slight movement in space horizontally or vertically. The coefficient of physical activity CFA is not more than 1.6. Medium-weight works of the 2nd category are also divided into A And b and are associated with the constant movement of parts of the body or the entire body in space, objects and tools. These are partially mechanized types of labor. Coefficient of physical activity 2.0 3rd category of labor - heavy physical labor is associated with the constant movement of the body and load horizontally and vertically, CFA 2.2 and maybe more.

The coefficient of physical activity determines the ratio of total energy consumption to the cost of basal metabolism. The leading physiological criterion of physical types of labor is the dynamics of oxygen consumption during work and recovery time, as well as heart rate, functions nervous system, respiratory, metabolic processes. Static work is more tiring, blood circulation in tense muscles is difficult, anaerobic energy supply comes with the accumulation of lactic acid. Dynamic work is divided into general, regional and local, is the most common type of activity. General muscular work is performed with the involvement of a significant mass of skeletal muscles. Regional muscular work is carried out mainly by the muscles of the shoulder girdle and upper limbs. Local muscle work is performed with the participation of minor muscle groups.

Light physical work is often accompanied by monotony, which is a negative factor that leads to fatigue and reduced attention. Monotonous repeated movements lead to the development of the process of inhibition, distraction of attention, and a decrease in the speed of reactions. Such types of labor are noted in conveyor production, work in one operation, with operators, dispatchers. Such a concept as fatigue is associated with the processes of inhibition - a temporary decrease in working capacity, recovering after rest. The group of types of labor united as mental labor is determined by the tension of the sensory, emotional and mental sphere. With these types of labor, information is received, processed, and decisions are made. This includes the work of operators, managerial work, creative, pedagogical, student youth, and doctors. The principle of classification is based on the number of perceived signs and responsibility for the decisions made. Mental work is associated with neurophysiological changes in the brain - its blood supply increases, energy metabolism increases, indicators of bioelectrical activity change. Energy metabolism is up to 20% of the total metabolism, oxygen consumption is 5 times greater than that consumed by the skeletal muscle of the same volume. At the time of making a responsible decision and with a shortage of time, significant changes are noted in cardiohemodynamics and respiration. Mental types of labor are accompanied by hypodynamia, forced working postures. The physiological picture of physical and mental labor is similar. During mental work, muscle fatigue is also constantly observed. The resumption of work against the background of fatigue leads to overwork, which is characterized by headaches, a feeling of heaviness in the muscles, lethargy, absent-mindedness, decreased attention, memory, and sleep disturbance.

The severity of labor- this is a characteristic of the labor process, reflecting the predominant load on the musculoskeletal system and functional systems of the body (cardiovascular, respiratory, metabolic, excretory), which provide the labor process. The severity of labor is characterized by both a static load, a working posture, the degree of inclination of the body, and a dynamic load - the mass of the load being lifted and moved horizontally and vertically, moving in the space of the body itself, total number stereotypical work movements. All these types of dynamic and static loads can take place in different working conditions - in optimal, permissible, harmful and dangerous - 4 degrees of labor severity, 4 classes: light, permissible, medium, heavy.

Labor intensity- this is a characteristic of the labor process, reflecting the load mainly on the central nervous system, sensory organs, and the emotional sphere of the employee. The factors characterizing the intensity of labor include: intellectual, sensory, emotional stress, the degree of monotony of loads, work mode - 4 classes and degrees: optimal, acceptable, stressful, very stressful.

Evaluation by working posture, it can be free, fixed, uncomfortable, sitting, standing. According to the slope of the body, either this is a forced slope or this is the number of slopes per shift. The technological process sometimes requires the movement of the worker either horizontally or vertically. Accounting is in meters or kilometers per shift.

Evaluation of the intensity of labor is carried out by class, the degree of intensity. Class 1 - optimal conditions, light intensity of labor. Class 2 - acceptable, labor intensity of an average degree. Class 3 - hard work, subclasses 3.1, 3.2, 3.3. The highest degree of tension 3.3. Intellectual loads are taken into account by the need to make a decision; solving problems according to instructions; according to the algorithm; heuristic - creative activity. The next indicator of the degree of labor intensity is the perception of signals (information) and their correction, evaluation; with comparison with other signals, complex assessment. According to the nature of the work performed, individual plan, By established schedule: work with time pressure; with increased responsibility for final result. From sensory loads, the duration of observation concentration is determined; density of signals and messages per unit of time; by the size of the objects of distinction; work with optical devices; monitoring the screens of video terminals. The load on the vocal apparatus is taken into account separately - the number of hours spoken; on a hearing aid with discrimination and analysis of signals. According to the degree of emotional load - bears personal responsibility for the fulfillment of tasks, is responsible for the team; for product quality; for the safety of others. The degree of monotony of labor is determined by the number of elements per unit of time; the duration of the execution of repetitive operations, the monotony of the production environment. The mode of operation, the actual duration of the working day are especially taken into account. The optimal option is 6-7 hours per shift, the acceptable option is 8-9 hours, the harmful mode of operation is 10-12 hours. Shift work also plays a role in restoring body functions. The optimal class of working conditions is work without a night shift. Permissible conditions are two-shift work without night shifts. If the work is three-shift with night shift-- these are intense working conditions (class 3.3). By scientific organization labor and the dynamics of working capacity are established and regulated breaks, their duration. If the duration of the break is 7% of the duration of the work shift, this is the best option; from 7% to 3% - the permissible duration of the break and less than 3% - insufficient duration of the break to restore functions, overwork is possible.

From the standpoint of hazard analysis, it is advisable to consider human activity as a system (Fig. 1.3), consisting of two interconnected complex subsystems: “human (organism-personality)” and “habitat (production environment)”. The dangers generated by the system "man (organism-personality)" are determined by the anthropometric, physiological, psychophysical and psychological capabilities of a person to perform production activities. They are discussed in this chapter.

Human activity is of the most diverse nature. Despite this, it can be divided into three main groups according to the nature of the functions performed by a person (Fig. 2.1).

Physically, labor is called physical labor (work) when a person performs energy functions in the system “man-tool of labor”.

Physical work requires significant muscle activity. It is divided into two types: dynamic and static. Dynamic work is associated with the movement of the human body, his HANDS, legs, fingers in space; static - with the impact of the load on the upper limbs, the muscles of the body and legs when holding the load, when doing work while standing or sitting. Dynamic physical work, in which more than 2/3 of the human muscles are involved in the process of labor activity, is called general, with participation in work from 2/3 to 1/3 of the human muscles (muscles of the body, legs, arms only) - regional,at local less dynamic physical work 1/3 muscles (for example, typing on a computer).

The physical severity of work is determined by energy costs in the process of labor activity and is divided into the following categories: light, moderate and heavy physical work.

Rice. 2.1- Main forms of human activity

light physical work(category I) are divided into two categories: 1a, in which the energy consumption is up to 139 W, and 16, in which the energy consumption is 140-174 W. Category 1a includes work performed while sitting and accompanied by little physical effort. Category 1b includes work performed while sitting, standing or walking and accompanied by some physical effort.

Physical work secondary severity (category II) are divided into two categories: Pa, at which the energy consumption is 175-232 W, and 116, at which the energy consumption is 233-290 W. The category Pa includes work associated with constant walking, moving small (up to 1 kg) products or objects in a standing or sitting position and requiring certain physical efforts. The PB category includes work related to walking, moving and carrying loads weighing up to 10 kg and accompanied by moderate physical effort.

Heavy physical work characterized by energy consumption of more than 290 watts. This category includes work associated with constant movement, movement and transfer of significant (over 10 kg) weights and requiring great physical effort.

Energy costs for muscle work. The energy expenditure for muscular work in labor (above the level of rest and regardless of the influence of emotions associated with work, the influence of air temperature, etc.) can be calculated for the average worker as the sum of the expenses for maintaining the working posture and for the mechanical work performed by the muscles.

Mechanized forms of physical labor in the man-machine system. A person performs mental and physical functions. The activity of a person (hereinafter, a human operator) occurs according to one of the processes:

deterministic - according to previously known rules, instructions, algorithms of actions, a rigid technological schedule, etc.:

non-deterministic - when unexpected events are possible: events in the ongoing technological process, unexpected appearance of signals, but at the same time, control actions are known when unexpected events occur (rules, instructions, etc.) are known in the ongoing process.

There are several types of operator activities in technical systems ah, classified i depending on the main function performed by a person, and the docks of mental and physical loading included in the operator's work.

The operator-technologist is directly involved in the technological process, works in the main mode of immediate service, performs mainly executive actions, guided by instructions that clearly regulate actions, containing, as a rule, a complete set of situations and decisions. These are the operators of technological processes, automatic lines etc.

Operator-manipulator (driver). The main role in its activity is played by the mechanisms of sensorimotor regulation (execution of actions) and, to a lesser extent, conceptual and figurative thinking. Among the functions performed by him are the management of individual machines and mechanisms.

Operator-observer, controller (for example, a dispatcher of a production line or a transport system). His work is dominated specific gravity information and conceptual models. The operator works both in the mode of immediate and delayed maintenance on a real (real) time scale. In his activity, the apparatus of conceptual thinking and the experience embedded in figurative-conceptual models are largely used. Physical work plays an insignificant role here.

The functioning of the body requires the occurrence of chemical and biochemical processes in it within fairly strict temperature limits. For body temperature, this interval is in the range of 36.5-37.0 o C.

In the process of human interaction with the environment, body temperature can change significantly, which is associated with temperature, humidity and air mobility in the environment, as well as thermal radiation from various kinds equipment used in the production environment. The adaptation of the human body to changes in the parameters of the state of the environment is expressed in the ability of the processes of thermoregulation to occur in it.

Thermoregulation - a set of physiological and chemical processes in the human body aimed at maintaining a constant body temperature (“36-37 ° C). This ensures the normal functioning of the body, contributes to the flow of biochemical processes in the human body. Thermoregulation (Q eliminates hypothermia or overheating of the human body. Maintaining a constant body temperature is determined by the heat production of the body (M), those. metabolic processes in cells and muscle tremors, heat transfer or heat gain (R) due to infrared radiation that radiates or receives the surface of the body; heat transfer or heat gain due to convection (C, i.e. through heating or cooling the body with air washed over the surface of the body; heat transfer (E) due to the evaporation of moisture from the surface of the skin, mucous membranes of the upper respiratory tract, lungs. Thermoregulation, thus, provides the balance between the amount of heat continuously generated in the body and the excess heat continuously given off in environment, i.e. maintains the thermal balance of the body.

Thermoregulation can be represented by the following expression:

IN normal conditions with weak air movement, a person at rest loses about 45% of all thermal energy generated by the body as a result of thermal radiation, up to 30% by convection and up to 25% by evaporation, while over 80% of heat is given off through the skin, approximately 13% through the respiratory organs, about 7% of heat is spent on warming food, water and inhaled air. When the body is at rest and the air temperature is 15 ° C, sweating is insignificant and is approximately 30 ml for 1 hour At high temperature (30 ° C and above), especially when performing hard physical work, sweating can increase tenfold. So, in hot shops with increased muscular work, the amount of sweat released is 1-1.5 l / h, the evaporation of which takes about 2500 ... 3800 kJ.

There are acute and chronic forms of violation of thermoregulation. Acute forms of violation of thermoregulation:

Thermal hyperthermia - heat transfer at a relative humidity of 75 ... 80% - a slight increase in body temperature, profuse sweating, thirst, a slight increase in breathing and heart rate. With more significant overheating, shortness of breath, headache and dizziness also occur, speech becomes difficult, etc.

Convulsive disease - the predominance of a violation of water-salt metabolism - various cramps, especially of the calf muscles, and accompanied by a large loss of sweat, a strong thickening of the blood. The viscosity of the blood increases, the speed of its movement decreases and therefore the cells do not receive the required amount of oxygen.

Heatstroke is a further course of convulsive illness - loss of consciousness, fever up to 40-41 ° C, weak rapid pulse. A sign of severe damage in heat stroke is the complete cessation of sweating.

Heat stroke and convulsive illness can be fatal.

Chronic forms of violation of thermoregulation lead to changes in the state of the nervous, cardiovascular and digestive systems of a person, forming work-related diseases.

Prolonged cooling often leads to disruption of the activity of capillaries and small arteries (chilling of the fingers, toes and tips of the ears). At the same time, hypothermia of the whole organism occurs. Cold-induced diseases of the peripheral nervous system are widespread, especially sciatica, neuralgia of the facial, trigeminal, sciatic and other nerves, exacerbations of articular and muscular rheumatism, pleurisy, bronchitis, aseptic and infectious inflammation mucous membranes of the respiratory tract, etc.

Humid air conducts heat better, and its mobility increases heat transfer by convection - this leads to great frostbite (even death) under conditions of low temperature, high humidity and air mobility.

There are three stages of cooling the human body, which are characterized by the following indicators:

I-II stage body temperature from 37 to 35.5 ° C. In this case, the following occurs:

Spasm of skin vessels;

Decreased heart rate;

Decrease in body temperature;

Increased blood pressure;

Increased pulmonary ventilation;

Increase in heat production

Thus, within the limits of up to 35 ° C, the body tries to fight on your own against a cooling microclimate.

Stage III - body temperature below 35 ° C. When this happens;

Drop in body temperature;

Decreased activity of the central nervous system;

Decreased blood pressure;

Decreased pulmonary ventilation;

Decrease in heat production.

Illnesses caused by cold: frostbite, swelling of the elbows and feet, acute respiratory infections and influenza.

Creating a favorable microclimate of the working area is a guarantor of maintaining the body's thermoregulation, increasing the efficiency of a person in production.

Mental labor (intellectual activity). This work combines works related to the reception and processing of information, requiring a predominant tension of attention, sensory apparatus, memory, as well as the activation of thought processes, emotional sphere(management, creativity, teaching, science, study, etc.).

Operator work - characterized by great responsibility and high neuro-emotional stress. Managerial work - is determined by an excessive increase in the volume of information, an increase in the lack of time for its processing, an increase in personal responsibility for decision-making, and the periodic occurrence of conflict situations. Creative work- requires a significant amount of memory, tension of attention, neuro-emotional stress. Teacher's work constant contact with people, increased responsibility, lack of time and information for making a decision - this causes a high degree of neuro-emotional stress. Student's work memory, attention, perception, the presence of stressful situations.

With intensive intellectual activity, the brain's need for energy increases, amounting to 15 ... 20 % of the total volume in the body. At the same time, the oxygen consumption of 100 g of the cerebral cortex turns out to be 5 times more than the skeletal muscle of the same weight consumes at maximum load. Daily energy consumption during mental work ranges from 10.5 to 12.5 MJ. So, when reading aloud, energy consumption increases by 48%, when delivering a public lecture - by 94%, for computer operators - by 60-100%.

When a person performs mental work with neuro-emotional stress, there are shifts in the vegetative functions of a person: an increase in blood pressure, a change in the ECG, an increase in pulmonary ventilation and oxygen consumption, an increase in body temperature. At the end of mental work, fatigue remains longer than during physical work.

When operating technical systems in any area of ​​the environment, the human manager controls not the technical components of the system or a separate machine, but other people. Management is carried out both directly and indirectly - through technical means and communication channels. This category of personnel includes organizers, managers various levels responsible decision makers who have relevant knowledge, experience, decision-making skills, intuition and take into account in their activities not only the capabilities and limitations of technical systems and their components, but also the full features of subordinates - their capabilities and limitations, states and moods .

The severity and intensity of work. The severity of labor is a quantitative characteristic of physical labor. Labor intensity is a quantitative characteristic of mental labor. It is determined by the amount of information load.

In production, there are four levels of influence of factors of working conditions on a person:

Comfortable working conditions provide optimal dynamics of human performance and the preservation of his health;

Relatively uncomfortable working conditions, when exposed for a certain period of time, provide a given performance and health preservation, but cause subjective sensations and functional changes that do not go beyond the norm;

Extreme conditions labor lead to a decrease in a person's working capacity, do not cause functional changes that go beyond the limits of the norm, but do not lead to pathological changes;

Super-extreme working conditions lead to the occurrence of pathological changes in the human body and to disability.

The medical and physiological classification of the severity and intensity of labor is carried out on the basis of a comprehensive quantitative assessment of the factors of working conditions, called the integral value of the severity and intensity of labor (I t).

Category I includes work performed in optimal working conditions with favorable loads. Category II includes work performed under conditions corresponding to the maximum permissible values ​​of production factors. Category III includes work in which, due to not quite favorable working conditions, people develop reactions characteristic of the borderline state of the body (deterioration of some indicators of the psychophysiological state by the end of work). Category IV includes jobs in which unfavorable working conditions lead to reactions characteristic of a pre-pathological condition in most people. Category V includes works in which, as a result of exposure, very adverse conditions labor in people at the end of the working period, reactions are formed that are characteristic of the pathological functional state of the body. Category VI includes jobs in which such reactions are formed shortly after the start of the working period (shift, week).

The category of severity and intensity of labor is determined by calculation. For this, each factor working conditions evaluated on a six-point system using special tables. The integral assessment of the severity and intensity of labor is calculated by the formula:

When assessing the severity of physical labor, indicators of dynamic and static load are used. Dynamic load indicators:

The mass of the lifted and moved cargo manually;

Distance of cargo movement;

The power of the work performed: when working with the muscles of the lower extremities and torso, with the predominant participation of the muscles of the shoulder girdle;

Small, stereotyped movements of the hands and fingers, the number per shift;

Movement in space (transitions due to the technological process), km.

Static load indicators:

Weight of the retained cargo, kg;

Duration of holding the load, s;

Static load per shift, N, while holding the load:

with one hand, two hands, with the participation of the muscles of the body and legs;

Working posture, being in an inclined position, the percentage of shift time;

Forced tilts of the body more than 30°, quantity per shift;

Linear spatial layout parameter of elements of production equipment and workplace, mm;

Angular spatial and layout parameter of the elements of production equipment and workplace, viewing angle;

- the value of the resistance of the drive elements of the controls (the force required to move the controls), N.

Dynamic physical load is determined, as a rule, by one of the following indicators: 1) work (kg-m); 2) power of effort (W); static physical load is determined in kg / s.

To determine the dynamic work performed by a person in each individual segment of the work shift, it is recommended to use the following formula:

W=( РН + (РL/9) + (РН 1/2))К:

where W - work, kg m; R-- mass of cargo, kg; H-height, on the second place a load from starting position, m; L is the distance over which the load is moved horizontally, m; H 1 - drop distance cargo, m; TO- coefficient equal to 6.

To calculate the average shift power, you should sum up the work done by a person for the entire shift and divide it by the duration of the shift:

where N is the power, W, t is the duration of the exchange, s; K 1 - work conversion rate (W) from kg.m to Joule (J), equal to 9.8.

A static load is an effort on a person's muscles without moving the body or its individual parts. The magnitude of the static load is determined by the product of the magnitude of the effort by the maintenance time (in the case of different magnitudes of efforts, the maintenance time of each of them is determined separately, the products of the magnitude of the effort by the maintenance time are found, and then these products are summed up).

When assessing the intensity of mental labor, indicators of attention, the intensity of visual work and hearing, and the monotony of labor are used.

The severity of the labor process

The severity and intensity of labor are characterized by the degree of functional stress of the body. It can be energetic, depending on the power of work - during physical labor, and emotional - during mental labor, when information overload occurs.

The physical burden of labor- this is a load on the body during labor, requiring mainly muscle effort and appropriate energy supply. The classification of labor according to severity is made according to the level of energy consumption, taking into account the type of load (static and dynamic) and the muscles being loaded.

- the process of muscle contraction, leading to the movement of the load, as well as the human body itself and its parts in space. In this case, energy is spent both on maintaining a certain tension in the muscles, and on the mechanical effect of work. The value of the dynamic load is determined by the formula:

where A - dynamic load, kgm; m is the mass of the load or the applied force, kg; H is the height of the load, m; l- distance of cargo movement, m; G is a factor equal to 6.

In accordance with the evaluation criteria for a regional load (work with the predominant participation of the muscles of the arms and shoulder girdle) up to 2500 kgm, it is considered optimal (light), up to 5000 kgm - acceptable (medium), and if the latter value is exceeded, working conditions are considered harmful (hard work ) three degrees of severity depending on the excess.

Evaluation of the mass of the processed cargo allows us to classify working conditions as optimal (up to 15 kg), permissible (up to 30 kg) or harmful working conditions of the 1st degree of severity. The second and third degrees of severity are absent, since manual processing of goods weighing more than 30 kg is not allowed.

associated with the expenditure of human effort without moving the body or its individual parts. It is characterized by the value of the retained load (or applied force) and the time it is held in a static state and is calculated by the formula

Where m- mass of cargo or static force, kg; t- effort fixation time, s. To calculate the static load, it is necessary to determine not only the mass of the load being held, but also to indicate the group of muscles involved. So, with a light load (optimal class of working conditions), the value of the static load per shift when holding the load with both hands should not exceed 18,000 kgf, while holding the load with the participation of the muscles of the body and legs - 43,000 kgf, and when working of medium severity - respectively 36 000 and 100,000 kgf.

In addition to the static and dynamic load and the mass of the load being lifted and moved, the assessment of working conditions according to the severity of the labor process is carried out according to the working posture, the number of inclinations per shift, the number of stereotyped work movements and movement in space due to the technological process.

The optimal working posture is determined by the correspondence of the working surface and the chair. Optimal conditions allow up to 50 slopes per shift. If slopes with an angle of more than 30 degrees reach 100 times per shift, then the conditions are considered acceptable.

With repetitive working movements of the muscles of the hands and fingers up to 20,000, working conditions are considered optimal. Over 20,000 to 40,000 are acceptable. If the number of movements reaches 60,000, then the working conditions are classified as harmful - 1st degree.

Under the movement in space understand the transitions during the shift, due to the technological process. Walking up to 4 km - optimal working conditions; from 4 to 10 km - permissible, and up to 15 km and more - respectively, harmful working conditions of the 1st and 2nd degree. The third degree of assessment of movements in space is not provided.

PROTOCOL

assessment of working conditions in terms of the severity of the labor process

FULL NAME. Ivanov I.I.

Gender: Male

Profession: Locksmith

Production: STO

Brief description of the work performed.

Repair and assembly of diesel and special trucks and buses with a length of over 9.5 m. Dismantling, repair, assembly of complex units, units and devices and their replacement during maintenance. Running in cars and buses of all types at the stand. Identification and elimination of defects, malfunctions in the process of adjustment and testing of units, assemblies and devices. Disassembly of parts after disassembly and washing. Locksmith processing of parts according to 7-10 qualifications (2-3 classes of accuracy) using universal devices. Static and dynamic balancing of critical parts and assemblies of complex configuration. Compilation of defect reports.

Must know: device and purpose of diesel and special trucks and buses; electrical and wiring diagrams of cars; specifications assembly, repair and adjustment of units, components and devices; methods for identifying and ways to eliminate complex defects found in the process of repair, assembly and testing of units, assemblies and devices; rules and test regimes, specifications for testing and delivery of units and assemblies; purpose and rules for the use of complex test facilities; device; purpose and rules for the use of a complex measuring instrument; design of universal and special devices; frequency and volume Maintenance electrical equipment and main components and assemblies of vehicles; a system of tolerances and fits, qualifications (classes of accuracy) and roughness parameters (classes of cleanliness of processing).

Work examples:

1. Engine cylinder blocks - repair and assembly with a crank mechanism.

2. Camshafts - installation in the block.

3. Generators, starters, speedometers - disassembly.

4. Hydraulic lifts of the dumping mechanism - test.

5. Torque converters - inspection and disassembly.

6. Diesel engine cylinder heads - assembly, repair, leak test, installation and fastening.

7. Engines of all types - repair, assembly.

8. Front wheels - adjustment of the angle of convergence.

9. Brake shoes, shock absorbers, differentials - repair and assembly.

10. Compressors, brake valves - dismantling, repair, assembly, testing.

11. Automatic transmissions - disassembly.

12. Mechanical gearboxes - assembly, bench testing.

13. Dump truck bodies, dumping mechanisms - installation, adjustment of lifting and lowering.

14. Front and rear axles, clutches, cardan shafts - repair, assembly and adjustment.

15. Axles forward - check and editing under a press in a cold state.

16. Main bearings - replacement of liners, scraping, adjustment.

17. Pistons - selection by cylinders, assembly with connecting rods, change of piston rings.

18. Instruments and assemblies of electrical equipment are complex - verification and adjustment during maintenance.

19. Reducers, differentials - repair, assembly, testing and installation in the rear axle housing.

20. Relay-regulators, ignition distributors - repair, disassembly.

21. Crankshaft oil seal, clutch hubs, steering ball pins, rotary cams - replacement.

22. Hydraulic and pneumatic brakes - disassembly.

23. Steering - repair, assembly, adjustment.

24. Connecting rods in assembly with pistons - check on the device.

25. Connecting rods - change of bushings in the upper head of the connecting rod with adjustment to the piston pin; final fit on the crankshaft journals on a plumb line in four positions.

26. Car electrical wires - installation according to the scheme.

The car mechanic takes a set of keys (2kg), a hammer (0.5kg), a chisel (0.25kg), a disk (1.5kg) a distance (2m), performs the operation of replacing the gearbox.

Let's do the calculation:

(2+0.5+0.25)*4+45*3+1.5*0.5= 554 kg*m - class 1

2 Weight of manually lifted and moved load, 50.75 kg - class 1

3 Stereotypical movements: - Number of movements - 70%

336min*30=1008 - class 2

Key weight - 0.25 kg

50% = 14400 sec

14400 0.25 = 3600 kg s - class 1

5 Working posture: free - class 3.2

6 Body tilts per shift 50 - 100 - class 2

7 Movement in space: the locksmith makes movements in the horizontal direction. The movements are significant.

6000m=6km - class 1.

Regional - movement of cargo up to 1 m

The general loading of movement: movement of freight: - from 1 to 5 m;

More than 5m

With one hand;

two hands;

With the participation of the muscles of the body and legs

Item number	Indicators	Actual values
	The mass of the load lifted and moved manually, kg: When alternating with other work Constantly during the shift Mass of one-time lifting of cargo The total weight of the load during each hour of the shift With work surface;
	Stereotypical work movements:
	working posture	free
	Hull slopes (number per shift).
	Moving in space Horizontally Vertically
Final assessment of the severity of labor 3.2