Quantitative assessment of the severity and intensity of the labor process is carried out in accordance with Guideline R 2.2.755-99 “Hygienic assessment criteria and classification of working conditions according to indicators of harmfulness and danger of factors in the working environment, severity and intensity of the labor process.”

The severity of labor is a characteristic of the labor process, reflecting primarily the load on the musculoskeletal system and the functional systems of the body (cardiovascular, respiratory, etc.) that ensure its activity.

The levels of labor severity factors are expressed in ergometric values ​​that characterize the labor process, regardless of the individual characteristics of the person participating in the process.

The main indicators of the severity of the labor process are:

mass of lifted and moved cargo;

total number of stereotypical labor movements;

static load value;

working posture;

degree of body tilt;

movement in space.

Labor intensity is a characteristic of the labor process, reflecting the load primarily on the central nervous system, sensory organs, and emotional sphere of the worker.

Factors characterizing labor intensity include:

intellectual loads;

sensory loads;

emotional stress;

degree of monotony of loads;

operating mode.

Hygienic criteria for assessing working conditions based on the severity of the labor process.

The assessment of the severity of the labor process is presented respectively in table. 6.1.

Table 6.1.

Classes of working conditions according to indicators of the severity of the labor process.

Indicators of the severity of the labor process	Class of working conditions
	Optimal	Acceptable	Harmful
			(hard labour)
			1st degree	2 degrees
	1	2	3.1	3.2
1	2	3	4	5
1.Physical dynamic load (units of external mechanical work per shift, kg m)
1.1. With regional load (with the predominant participation of the muscles of the arms and shoulder girdle) when moving the load over a distance of up to 1 m:
for men				More than 7000
for women				More than 4000
1.2. With a general load (involving the muscles of the arms, body, legs):
1.2.1. When moving a load over a distance of 1 to 5 m
for men				More than 35000
for women				More than 25000
1.2.2. When moving a load over a distance of more than 5 m
for men				More than 70000
for women				More than 40,000
2. Mass of the load lifted and moved manually, kg
2.1. Lifting and moving (one-time) heavy objects when alternating with other work (up to 2 times per hour):
for men
for women
2.2. Lifting and moving (one-time) heavy objects constantly during the work shift:
for men
for women
2.3. The total mass of goods moved during each hour of the shift:
2.3.1. From the work surface
for men				more than 1500
for women
2.3.2. From the floor
for men
for women

Continuation of Table 6.1.

3. Stereotypical work movements (number per shift)
3.1. With local load (involving the muscles of the hands and fingers)				more than 60000
3.2. With regional load (when working with the predominant participation of the muscles of the arms and shoulder girdle)				more than 30,000
4. Static load - the amount of static load per shift when holding a load, applying force, kgfsec)
4.1. With one hand: for men - for women -				more than 70000 more than 42000
4.2. With two hands: for men - for women -				more than 140000 more than 84000
4.3. With the participation of the core and leg muscles: for men - for women -				more than 200000 more than 120000
5. Working posture
5. Working posture	Free, comfortable posture, the ability to change the working position of the body (sitting, standing). Standing in a standing position up to 40% of the shift time.	Periodically, up to 25% of the shift time, being in an uncomfortable position (working with turning the body, inconvenient placement of limbs, etc.) and/or a fixed position (impossibility of changing the relative position of different parts of the body relative to each other). Standing in a standing position up to 60% of the shift time.	Periodic, up to 50% of the time shifts, being in an uncomfortable and/or fixed position; staying in a forced position (kneeling, squatting, etc.) up to 25% of the shift time. Staying in a standing position up to 80% of the shift time	Periodically, more than 50% of the shift time, being in an uncomfortable and/or fixed position; staying in a forced position (kneeling, squatting, etc.) more than 25% of the shift time. Standing in a standing position for more than 80% of the shift.
6. Body tilts
6. Body tilts (forced more than 30 O), number per shift
7. Displacements in space due to the technological process, km
7.1. Horizontally 7.2. Vertically

So, labor, depending on the nature of a person’s activity,

trap can be divided into physical, connected in

mainly with static or dynamic load on

muscles, and mental, associated mainly with the load on

certain groups of analyzers (visual, auditory,

tactile). If the severity of physical labor can be

estimated by the load placed on the human muscles during the

time, then the severity of mental labor

can only be assessed by its intensity.

According to the degree of physical difficulty of work are divided into:

· light – not requiring systematic physical

voltage (Ib) – energy consumption up to 152 W and from 153 to 176 W;

moderate severity – associated with constant walking and

moving small (up to 1 kg) objects (IIa), as well as connected

exercises involving walking and carrying small (up to 10 kg) weights

and with moderate voltage (IIb) - energy consumption 176-234 W

stress and movement (over 10 kg) of heavy objects –

energy consumption over 292 W.

During physical activity, energy occurs

genetic exchange, more intense than with mental

activities. The intensity of heat exchange in the body is determined by

divided by microclimate: temperature, humidity, speed

the intensity of air movement and the presence of heat flows.

There are absolute, maximum and relative

new air humidity:

absolute – the amount of water vapor contained

per unit volume (g/m3);

· maximum – the maximum possible number of

carbon vapor that can be contained per unit volume

air at a given temperature without condensation into droplets

noah phase;

relative – the ratio of absolute humidity to

maximum at a given temperature, expressed in pro-

When the ambient temperature changes, the organ-

nism needs time to adapt, and a long stay

operation in conditions of high or low temperature

associated with acclimatization, which leads to additional

load on thermoregulation mechanisms.

Release of excess heat generated during the process

vital activity of the body occurs mainly through

skin and lungs due to radiation (approximately 44% of emitted

heat), convection (31%) and evaporation (21%). Due to heating the air

Spirit in the lungs loses approximately 4% of the heat generated.

The amount of heat given off by a body due to radiation in

direction of the surface with a lower temperature, sub-

obeys the Stefan-Boltzmann law and is proportional to

body surface area, difference in fourth powers of temperature

temperatures of the body and surface and the degree of blackness of the body (for ab-

for a black body this coefficient is equal to 1, for grains

highly reflective - close to 0).

Heat loss due to convection, i.e. heat transfer from

surface of the body to less heated air flowing around it,

proportional to body area, body temperature difference and

air and the speed of the air flow blowing over the body.

At zero flow velocity, convective heat transfer is sub-

maintained due to air movement caused by dis-

by the density of the heated body near the body and the colder one

ambient air.

Heat loss due to evaporation is proportional to the

area of ​​the body from which sweat evaporates, relative

temperature of the air and the speed of the blowing air

nogo flow.

Providing comfortable conditions

Life activity

One of the main tasks of the organization’s management is

ensuring normal operating conditions for work

nicknames After all, taking care of employee health, improving conditions

labor and its safety lead to increased production

labor activity, which is also one of the main tasks

manuals. At the same time, this solves such a problem as

costs of paying for health insurance, benefits and compensation

tions for working in unfavorable conditions. Regardless

spheres of activity (physical or intellectual

labor) conditions influence its result.

System for providing microclimate parameters

And the composition of the air

So that working conditions do not become the reason for the above-

identified “problems” and did not reduce labor productivity,

it is necessary to monitor the cleanliness of the air, so that meteorologists

The physical conditions corresponded to the normal level. Com-

Fortified conditions are:

· air temperature in the workplace;

· indoors during the warm period 18-22;

· indoors during the cold period 20-22;

· outdoors during the warm period 18-22;

· outdoors during the cold period 7-10;

· relative air humidity 40-60%;

· air movement speed 0.1-0.2 m/s;

· toxic substances (multiplicity of maximum permissible concentration)me-

· industrial dust (multiplicity of MPC exceedance)me-

Microclimate parameters of production premises

They are standardized by GOST 12.1.005-88 “SSBT. General sanitary

hygienic requirements for the air in the working area." Basic

The new principle of rationing is the creation of optimal conditions

labor for a person under a certain physical activity.

This takes into account the severity of the work performed, the presence

indoor sources of sensible heat and time of year.

Work zone– this is a space up to two meters high

above floor level. Permanent workplace- this is the place where

the employee stays in the tor continuously for more than two hours.

The year is divided into 2 periods - warm (average daily temperature

temperature above +10) and cold (temperature +10 and below).

When working with neuro-emotional stress,

zheniya (in cabins and at control posts of various technical

nological processes, in the halls where there is computing

equipment, etc.), the air temperature should be

22-24 at humidity 40-60% and speed of movement

air up to 0.1 m/s. Auxiliary microclimate parameters

premises (design offices, libraries, premises

management services) are installed in accordance with the construction

official norms and rules.

The specialists conducting the examination pay an important role to the physical stress that the employee endures. For some types of diseases, they are strictly contraindicated, or, at a minimum, should be limited and within the framework of sanitary standards.

The physical severity of labor for VTEK is determined by the number of actions performed and the amount of effort exerted for certain types of activity. In many cases, additional costs lead to exhaustion of the body. And some diseases provoke physical suffering for the employee, causing pain.

They are divided according to tension indicators as follows:

1. Conditions that are comfortable for the body as a whole and comply with sanitary standards.
2. Conditions that comply with established standards in general, but have specific characteristics that cause some discomfort in the employee (noise, cold, hot shop, etc.).
3. Extreme working conditions accumulate chronic fatigue and require excessive physical and mental stress.

   Refers to conditions of increased danger during the course of certain diseases, but do not lead to disturbances and the development of pathologies in a healthy body (work in the far north, work in mines, metallurgical shops, etc.).

4. Ultra-extreme operating conditions that negatively affect not only a weakened, but also a healthy body, leading to the development of diseases (work in the Far North in the open air and/or with longer working hours, work in mines, some types of activities for miners and etc.)

To the number of these characteristics are added types of labor intensity, which are determined by its intensity. Here, the leading role is played by information loads that affect the brain activity of the body. When determining them, the energy consumption of the body is calculated:

• during shift work;
• based on the number of movements performed;
• monotony and specific posture.

Each unit of action (blocking action) is defined as an interaction of neural signals.

Comfortable working conditions are limited to 75 units, while for hard work the number of units should not exceed 176 units.

In general, in addition to tension, the document identifies a number of factors that influence the development of disability of citizens, causing occupational and other diseases. They are defined as factors of the production environment. These include:

1. Physical factors, such as temperature, humidity, gas pollution, noise and other conditions in which the production process takes place.
2. Chemical factors commonly encountered in pharmaceutical and similar industries.
3. Biological – occurring upon contact with microorganisms, bacteria, viruses, etc.

The hazards of working environment factors contain 4 types (classes), where class 1 and 2 work do not negatively affect the worker’s body, work is carried out in a healthy, optimal manner. In class 3, subgroups are distinguished according to the degree of harmfulness:

1. The harmful effects are compensated by rest and may not bring negative consequences due to self-purification and self-restoration of vitality.
2. They cause persistent pathologies after prolonged contact with the body, usually within 15 years of activity in the designated conditions.
3. They pose a risk of developing pathology of individual organs and tissues and allow complete loss of ability to work and normal life activities.
4. They arise in conditions of extreme and super-extreme types of labor intensity. Every shift is fraught with risk to life. Exposure to harmful factors usually leads to disorders.

Additional characteristics provide insight into the influences, provoking the development of unpleasant tendencies due to other reasons.

The additional characteristics themselves stem from natural processes and movements. But workers who constantly repeat them throughout the day wear out their body much faster. This point also comes into focus when examining citizens. These include:

1. Systematic standing position under physically heavy load, typical for installers, welders when installing heavy structures, etc.
2. Squatting position, bending position when working as welders, laying parquet or flooring, etc.
3. Sitting position when working drivers.
4. Bent position, mainly when working in agriculture.
5. Systematic hand strain when milking cows by hand.
6. The effect of vibrations on the body for tractor drivers, combine operators, machinists, and miners.
7. High pace of work, automation of movements when working on a conveyor.

To these characteristics are added walking throughout the working day, specific monotonous movements like those of construction workers involved in the same operations.

During the examination, mental types of stress that affect the stability of the nervous system and ongoing mental processes are also not ignored. They are often associated with factors of information oversaturation of the psyche.

Intensity of work activity under mental stress calculated in accordance with the number of operations performed per unit of working time.

Classification and criteria

When examining workers, norms and standards developed at the legislative level are applied. The basis regulating classification standards is the Order of the Ministry of Labor and Social Protection RF, under N 664n, which entered into force on September 29, 2014.

It announces provisions on classifications and criteria used by the ITU bureau at all levels - from local to federal. These criteria are universal and applicable in typical cases with the characteristics indicated in the list. The order was registered with the Ministry of Justice on November 20, 2014.

The general provisions reflect the classification rules. The classifier determines compliance with those categories of diseases that affect the wear and tear of the body, which leads it to pathologies.

Thus, the procedure for establishing disability is carried out summarily. The reasons for the decrease in the functioning of the body are derived, with the establishment of the admissibility of performing certain professional functions.

The third part establishes criteria for the limited means of life support for a citizen due to existing disorders. They are characterized by their abilities:

• self-service;
• independent movement;
• behavior control;
• communication and learning;
• to orientation;
• to work.

For working persons, the ratio of production load on the body is carried out. Indicators of the severity of work activity are established as the load on the musculoskeletal system, cardiovascular and respiratory systems, according to the types of work performed.

Each item is divided into 3 categories (degrees).

Second characterized by the fact that the performance of the designated functions is so difficult that it is necessary to use auxiliary means. For example, crutches, hearing aids, education in a special school, etc.

Third characterized by deep pathologies that cannot be corrected even with auxiliary means. Accordingly, the functions are maximally impaired.

In the fourth point methods for establishing disability groups are given. They are established in proportion to the depth of the violations. Respectively:

• Group 3 corresponds to disorders of the 1st degree;
• Group 2 – 2 degrees;
• 1 gr. – 3 degrees.

Experts examining the patient, based on the presented picture of the course of the disease, draw conclusions:

• about the need to transfer an employee to easier working conditions;
• prohibit labor activity.

This is expressed in, which is confirmed by the assignment of the corresponding disability group.

The established indicators are based on legislative provisions and acts of the Ministry of Health (ICD-10).

MSE for some diseases: list

Many diseases cause discomfort and require constant inpatient examination and treatment, but do not guarantee disability.

Particular attention is paid to hypertension. It may lead to the recognition of an individual's limited abilities, but not in all cases. The main reason is its prevalence in modern society., which is associated with ecology, stress, and a hypodynamic lifestyle.

Since high blood pressure can occur spontaneously, but after some time it can be eliminated as a result of treatment for a long period, it is not taken into account as a prerequisite for obtaining disability.

In addition to the characteristics given in the second and third provisions on the assignment of a disability group, violations of the so-called target organs are taken into account here, which, with constant attacks of pressure on the vessels, bring the body into the risk zone. They are manifested by organic disorders in the area of ​​cerebral vessels, as well as:

• cardiovascular disorders;
• renal dysfunction;
• peripheral vascular disorder;
• retinal dissection.

If diseases provoke myocardial infarction, stroke, intermittent claudication or blindness, a disability must be established until the citizen is fully restored.

As a rule, it is provided for high and very high risk (grade 3.4 disease), leading to diabetes mellitus, nephropathy and other associated conditions.

Rheumatoid arthritis– another common disease, against the background of which citizens experience systematic pain, suffering, and lose the ability to perform professional duties. It also takes into account the amount of damage caused to bone tissue, joints and joint fluid, the degradation of which is considered on a scale.

At the initial stages, until the destruction of the joints has reached the acceptable criterion for obtaining disability, it is recommended to maintain health in accessible ways. If no positive consequences occur, it is possible to recognize the restriction of rights.

Arthrosis changes in the joints of the arms and legs become visually diagnosed. Often such cases lead to complete helplessness of patients (approximately 10% of those examined) and require recognition of disability.

Chronic pancreatitis is a serious disease of the digestive tract. When recognizing a disability, attention is paid only to some of its forms:

• chronic recurrent pancreatitis;
• pancreatitis with acute persistent pain;
• pseudotumor;
• latent recurrent disease.

Patients with degree 2 of complexity are usually assigned to group 3 - as a result of a successful operation, until the body is restored.

At degree 3 of complexity, group 2 is prescribed if pancreatic fistulas and pseudocysts are present. And if the patient develops endocrine insufficiency with a pronounced degree of dystrophy, incessant pain and other similar consequences, group 1 is prescribed.

Conclusion

During the examination, it is required to present not only medical evidence of the presence of the disease, but also certificates of the nature of the work activity. Sometimes they help reveal the cause of disorders.

The assessment of the severity of the labor process is carried out based on taking into account all 18 indicators. In this case, the class is first established for each assessed indicator, and the final assessment of the severity of work is established according to the most sensitive indicator, which received the highest degree of severity. If there are two or more indicators of classes 3.1 and 3.2, working conditions in terms of the severity of the labor process are rated one degree higher (classes 3.2 and 3.3, respectively. According to this criterion, the highest degree of severity is class 3.3).

Indicators of the severity of the labor process are assessed consistently.

IN the group of indicators includes the following indicators: regional load (with the predominant participation of the muscles of the arms and shoulder girdle) when moving the load over a distance of up to 1 m, total load (with the participation of the muscles of the arms, body, legs) when moving the load over a distance from 1 to 5 m, total load (involving the muscles of the arms, body, legs) when moving the load over a distance of more than 5 m.

To calculate the physical dynamic load (external mechanical work), the mass of the load (parts, products, tools, etc.) moved manually in each operation and the path of its movement in meters are determined. The total number of load transfer operations per shift is calculated and the amount of external mechanical work (kg m) for the shift as a whole is summed up. Based on the amount of external mechanical work per shift, depending on the type of load (regional or general) and the distance of movement of the load, it is determined which class of working conditions this work belongs to.

For work that is caused by both regional and general physical stress during a shift, and is compatible with moving loads over various distances, the total mechanical work for the shift is determined, which is compared with a scale according to the average distance of movement.

The class of working conditions for this group of indicators is determined for men and women separately, which is due to the physiological characteristics of male and female organisms.

To the indicator group “the mass of the load lifted and moved manually” includes the following indicators: lifting and moving (one-time) weights when alternating with other work (up to two times per hour), lifting and moving (one-time) weights constantly during the work shift, the total mass of loads moved during each hour of the shift from the working surface , the total mass of goods moved during each hour of the shift from the floor.

Quantitative characteristics of physical dynamic load are presented in table. 3.1.

Table 3.1

Quantitative characteristics of physical dynamic load

Characteristic Definition	Characteristic values, kg m
With regional load (with the predominant participation of the muscles of the arms and shoulder girdle) when moving the load over a distance of up to 1 m
With a general load (involving the muscles of the arms, body, legs) when moving the load over a distance of 1 to 5 m
	More than 35,000	More than 25,000
With a general load (involving the muscles of the arms, body, legs) when moving the load over a distance of more than 5 m
	More than 70,000	More than 40,000

*KUT - classes of working conditions: class 1 (optimal), class 2 (permissible), class 3.1 (harmful 1st degree), class 3.2 (harmful 2nd degree).

To determine the mass of the load (lifted or carried by the employee during the shift, constantly or when alternating with other work), it is weighed on commercial scales. Only the maximum value is recorded. The weight of the cargo can also be determined from documents.

To determine the total mass of cargo moved during each hour of a shift, the weight of all cargo for the shift is summed up. Regardless of the actual duration of the shift, the total weight of cargo per shift is divided by 8, based on an 8-hour work shift.

In cases where manual movement of the load occurs both from the working surface and from the floor, the indicators should be summed up. If a larger load was moved from the working surface than from the floor, then the resulting value should be compared with this indicator, and if the greatest movement was made from the floor - with the indicator of the total mass of the load per hour 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 compared with the indicator of movement from the floor.

Quantitative characteristics of the mass of the load lifted and moved manually are presented in table. 3.2.

Table 3.2

Quantitative characteristics of the mass of the load lifted and moved manually

Characteristic Definition	Characteristic values, kg
Lifting and moving (one-time) heavy objects when alternating with other work (up to two times per hour)
Lifting and moving (one-time) heavy objects constantly during the work shift
The total mass of loads moved from the working surface during each hour of the shift
Total mass of loads moved from the floor during each hour of shift

The group of indicators “stereotypical working movements” includes the following indicators: stereotypical working movements with local load (with the participation of the muscles of the hands and fingers), stereotypical working movements with regional load (when working with the predominant participation of the muscles of the arms and shoulder girdle).

The concept of “labor movement” in this case implies an elementary movement, i.e. a single movement of the arms (or arm) from one position to another. Stereotypical working movements, depending on the amplitude of movements and the muscle mass involved in the movement, are divided into local and regional. Work characterized by local movements is usually performed at a fast pace (60-250 movements per minute), and the number of movements per shift can reach several tens of thousands. Since during these works the pace, i.e. the number of movements per unit of time practically does not change, then, having calculated, using some kind of automatic counter, the number of movements in 10-15 minutes, calculate the number of movements in 1 minute, and then multiply by the number of minutes during which this work is performed . The time for completing the work is determined by time-keeping observations or from photographs of the working day. The number of movements can also be determined by the number of characters printed (entered) per shift (the number of characters on one page is calculated and multiplied by the number of pages printed per day).

Regional working movements are performed, as a rule, at a slower pace, and it is easy to calculate their number in 10-15 minutes or in 1-2 repeated operations, several times per shift. After this, based on the total number of operations or the time it takes to complete the work, the total number of regional movements per shift is calculated.

Quantitative characteristics of stereotypical working movements are presented in table. 3.3.

Table 33

Quantitative characteristics of stereotypical work movements

The group of indicators “static load” includes the following indicators: the amount of static load per shift when holding a load with one hand, the amount of static load per shift when holding a load with two hands, and the amount of static load per shift when holding a load with the participation of the core and leg muscles.

The static load associated with holding a load or applying force is calculated by multiplying two parameters: the magnitude of the holding force (weight of the load) and the time it is held.

During work, static forces occur in various forms: holding the workpiece (tool), pressing the workpiece (product) to the workpiece (tool), efforts to move controls (handles, flywheels, steering wheels) or carts, etc. In the first case the magnitude 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 a scale. In the second case, the magnitude of the clamping force can be determined using strain gauges, piezoelectric crystals or other sensors that must be mounted on the tool or product. In the third case, the force on the controls can be determined using a dynamometer or from documents. The holding time of the static force is determined on the basis of timing measurements (or from a photograph of the working day). The assessment of the class of working conditions according to these indicators should be carried out taking into account the predominant load: on one, two arms or with the participation of the muscles of the body and legs. If, when performing work, two or three of the above loads are encountered (loads on one, two arms and with the participation of the muscles of the body and legs), then they should be summed up and the total value of the static load correlated with the indicator of the predominant load.

The class of working conditions for this group of indicators is also determined for men and women separately.

Quantitative characteristics of the static load are presented in table. 3.4.

Table FOR

Quantitative characteristics of static load

Characteristic Definition	Characteristic values, kg s
The magnitude of the static load per shift when holding a load with one hand
	More than 70,000	More than 42,000
The magnitude of the static load per shift when holding the load with both hands
	More than 140,000	More than 84,000
The magnitude of the static load per shift when holding a load with the participation of the core and leg muscles
	More than 200,000	More than 120,000

To the indicator group "working nose" includes the following indicators: free position, being in an uncomfortable and (or) fixed position, being in a forced position and being in a standing position.

The nature of the working posture (loose, fixed, uncomfortable, forced) is determined visually. TO free poses include comfortable sitting postures that make it possible to change the working position of the body or its parts (lean back in a chair, change the position of the legs, arms). TO uncomfortable positions These include postures with a large bend or turn of the body, with arms raised above shoulder level, and with uncomfortable placement of the lower extremities. Fixed posture - the impossibility of changing the relative position of various parts of the body relative to each other. Similar postures are encountered when performing work related to the need to distinguish small objects in the process of activity. The most rigidly fixed working postures are for representatives of those professions who have to perform their main production operations using optical magnifying devices - magnifiers and microscopes. TO forced poses include working positions lying down, kneeling, squatting, etc. The absolute time (in minutes, hours) spent in a particular position is determined on the basis of timing data for the shift, after which the time spent in relative values ​​is calculated, i.e. as a percentage of an 8-hour shift (regardless of the actual duration of the shift). If the nature of the work requires different working postures, then the assessment should be made based on the most typical posture for the job.

Working standing pose - the need for a working person to remain in an orthostatic position for a long time (either in a sedentary position or with movements between objects of work). Consequently, the time spent in a standing position will be the sum of the time spent working in a standing position and the time spent moving in space.

The class of working conditions for this group of indicators is determined completely for men and women.

Quantitative characteristics of the working posture are presented in table. 3.5.

Table 3.5

Quantitative characteristics of working posture

Definition characteristics	Characteristic values, quantity per shift
Being in an uncomfortable and/or fixed position
	Periodically, up to 25% of the shift time, being in an uncomfortable (working with rotation of the body, inconvenient placement of limbs, etc.) and (or) fixed position (impossibility of changing the relative position of different parts of the body relative to each other)
	Periodic, up to 50% of shift time
	More than 50% of shift time
Being in a forced position	Free, comfortable posture, the ability to change the working position of the body (sitting, standing)

End of table. 3.5

To the group "body tilts" The only indicator included is the body tilt itself (forced, more than 30°), the number per shift. The number of tilts per shift is determined by directly counting them per unit of time (several times per shift), then calculating the number of tilts for the entire time the work is performed, or by determining their number per operation and multiplying it by the number of operations per shift. The depth of the body slopes (in degrees) is measured using any simple device for measuring angles (for example, a protractor). When determining the angle of inclination, you do not need to use devices for measuring angles, since it is known that in a person with average anthropometric data, body tilts of more than 30° occur if he takes any objects, lifts a load or performs actions with his hands at a height of no more than 50 cm from the floor.

Classes of working conditions are determined on the following scale: up to 50 - class 1 (optimal), from 51 to 100 - class 2 (permissible), from 101 to 300 - class 3.1 (harmful 1st degree), more than 300 - class 3.2 (harmful 2nd degree)

IN group of indicators "movement in space" g.e. transitions caused by the technological process during a shift, either horizontally or vertically - along stairs, ramps, etc. includes the following indicators: horizontal movement and vertical movement.

The easiest way to determine this value is to use a pedometer, which can be attached to the employee’s body, to determine the number of steps per shift (remove the pedometer during regulated breaks and lunch breaks). Multiply the number of steps per shift by the step length (a man’s step in a production environment is on average 0.6 m, and a woman’s is 0.5 m) and express the resulting value in kilometers. Vertical movement can be considered movement along stairs or inclined surfaces, the angle of inclination of which is more than 30° from the horizontal. For professions associated with movement both horizontally and vertically, these distances can be summed up and compared with the indicator whose value was greater.

Quantitative characteristics of movement in space are presented in table. 3.6.

Table 3.6

Quantitative characteristics of movement in space

To assess the severity and intensity of work, various indicators and criteria are used. Usually there are four degrees of severity and intensity of work. As criteria for assessing the severity of work, both external indicators - work characteristics - and internal indicators - the cost to the body - are used. To assess tension, such a gradation is not always acceptable.

Assessment of the severity of work. The severity of physical labor is determined by the following indicators of dynamic and static work: the weight of the load being moved and the power of the work; the magnitude of the static load; the nature of the working posture.

The power of external work is determined by the amount of physical energy expended by a person. To calculate the power of external work, the amount of work performed per unit of time is calculated. Since physical work is associated with the movement of any cargo or materials over a distance, the calculation takes into account: lifting the load; moving it horizontally; lowering the load.

The work performed is calculated using the formula:

where A is the amount of work in kgm; P – cargo weight in kg; H – height of lifting the load from the initial state; 1 – distance of cargo movement horizontally; h – distance of lowering the load; k – coefficient equal to 6.

To calculate the power of work, the formula is used:

where N is the operating power in watts/sec.; A – amount of work in kgm; t is the time during which this work was completed in seconds; k – conversion factor kgm to watt, equal to 10.

The maximum size of the load being moved is the main indicator for determining the severity of labor.

In everyday life, static work manifests itself in two forms: maintaining a posture and holding a load. In most cases, when holding a load or maintaining a working posture, the counteracting force is gravity. In some cases, a static contraction may be aimed at overcoming another external force, such as pressing a pedal. The static load associated with a person maintaining an effort without moving the body or its individual parts is characterized by the magnitude of the retained load or effort. The static load is determined by the product of the force and the holding time. The magnitude of the static load is expressed in kg/s. An indicator of the static load is also the magnitude of the angles of inclination and the duration of stay in a particular position in full relation to the duration of the work shift. Posture is maintaining the human body in a certain position. The posture determines the psychological effect, which is expressed in the concept of comfort.

For practical assessment of the severity of work, we can recommend the indicators given in table. 1.

Table 1

Criteria for the severity of physical labor

Signs	Quantitative criteria for the severity of work (indicators of external work)
Physical labor	I – light		II – average		III – heavy		IV – very severe
Maximum size of transported load" kg
External work power, watts, with the participation of the shoulder girdle, with the participation of the lower extremities and torso
The magnitude of the static load per shift, kg/s" when creating forces; with both hands with the participation of the body and legs	up to 43,200 up to 61,200		up to 97,200 up to 129,600		up to 208,800 up to 266,400		over 208,800 over 266,400
Working posture and movement in space	Stationary workplace. Free pose.		Stationary workplace. Tilts up to 30"		Stationary workplace. Bend up to 30" 100–300 times per shift or stay		Stationary place. Bend up to 30" or more more than 300 times per shift or stay
				50–100 times per shift or stay in an inclined position up to 30 10–25% of working time. Walking up to 4 km per shift.		inclined position up to 30" 25–50% of working time. Walking up to 7 km per shift.		in an inclined position more than 50% of the working time. Walking up to 15 km per shift.
Physiological cost:		Quantitative criteria for the severity of labor (internal indicators - cost to the body)
by energy costs (basic metabolism - 1.1 kcal/min.);		150 kcal/hour. 172 J/sec.		150–200 172–232		200–300 232–293		over 300 over 293
by pulse rate (rest – 60–70 beats/min.; safety limit – 140–150 beats/min.)
by oxygen consumption (rest – 0.2 l/min.)		up to 0.5 l/min.		up to 0.8 l/min.		up to 1.5 l/min.		over 1.5 l/min.

Labor intensity characterizes that side of work activity that requires the mobilization of higher mental functions of a person, such as perception, attention, working memory, analytical and synthetic activity of the central nervous system. The different degrees of tension of these functions are little or almost not reflected in indicators such as gas exchange, energy consumption, and blood circulation. If we limit mental work to those types of activities that are widely used in production, and leave aside the highest forms of creative and performing work (scientists, artists, public figures), we can identify the following indicators used to assess the intensity of work: 1) the degree of attentional tension; 2) density of perceived signals; 3) pace of work; 4) work shift density; 5) tension of analytical functions; 6) degree of emotional stress; 7) intellectual tension; 8) monotony of work; 9) memory load; 10) shift work. Let's take a closer look at these indicators.

Attention. There is no single substantiated criterion for assessing attention intensity in production conditions (depending on the activity). It is recommended that the assessment of labor intensity according to the attention parameter be carried out according to production criteria. In relation to operator activities, we can talk about the number of objects of simultaneous observation or control, i.e. how many of the total number of objects of observation are the most important and require simultaneous observation. (For example, out of 100 objects, 5 or 10 are the most important and require constant observation: machines, console signals, essentially we are talking about the volume of the information field.) Another indicator characterizing attention is the duration of concentrated observation. This indicator is calculated as a relative value as a percentage of the total time of the work shift. Since the operator is required to be able to quickly switch attention, the frequency (average, maximum) of these switchings can serve as an indicator of labor intensity.

Density of perceived signals. This indicator characterizes the degree of labor intensity depending on the amount of incoming information per unit of time. An assessment of the degree of labor intensity according to this indicator should take into account the nature of the activity, the quantity and nature of the transformation of information. The calculation of signal density is calculated as the product of the number of information signs per unit of time. For example, the number of messages is 60, each message has 4 attributes. Total quantity – 4 × 60 = 240 per unit of time (usually per hour). Thus, this indicator characterizes the amount of information per unit of time.

Work shift pace and density. These indicators characterize the degree and uniformity of the workload per shift. Depending on the nature of the activity, two types of activity can be distinguished: 1) motor, 2) control-observational. An integral indicator of work shift density can be the “activity coefficient”. This is an indicator of the ratio of the total duration of active (regulatory, executive) actions to the total time of observation, control, but not the duration of the shift. The low weight of active actions with the need to maintain constant vigilance creates conditions for motivational conflict, which requires significant nervous tension (less than 0.2). At the same time, a too high “activity coefficient” (more than 0.8) reflects the strain of work associated with increased physical activity.

Tension of analyzer functions associated with the detection and isolation of signals of various modalities (vision, hearing, smell, tactile sensitivity). Based on physical strength, signals are divided into: 1) weak – below the operational threshold; 2) optimal – within the intervals of the operational threshold boundaries; 3) irritating – above the operational threshold. Another approach to assessing the degree of load on analyzers is to compare the degree of load with a category of standard indicators. The degree of visual strain is determined according to SN 245-75 category of visual work, where 6 categories of visual work are distinguished depending on the size of the object in the field of view. The degree of strain on the hearing organ can be determined in two ways. Firstly, by the audibility of speech depending on the distance or by the intelligibility of speech as a percentage of the ratio to the noise level. Secondly, according to the standards of permissible sound pressure levels and sound levels in workplaces.

table 2

Work intensity criteria

Signs		I – relaxed
1. Attention, the number of simultaneously observed objects; duration of concentrated observation (as a percentage of the duration of the work shift)
Vision. Dimensions of the object, mm, with a distance of the object to the worker’s eyes up to 1 m		more than 5 mm
		No interference
3. Signal (message) density
4. Amount of RAM. Must be remembered		up to 2 elements less than 2 hours
Memory load (by number of production process parameters)
5. Intellectual tension		No need to make independent decisions
6. Monotonicity: repeatability (per hour), number of elements in an operation, duration in seconds.		more than 10 more than 100
Time of active actions as a percentage of the shift duration (activity coefficient)		10–20% 0,5-0,3
7. Emotional stress		Work according to an individual plan
II – low tension	IV – very tense
	less than 0.3 mm
There is interference against which speech can be heard:
up to 2 elements	more than 5 elements
more than 2 hours	more than 5 hours
Simple work	Heuristic
instructions	(creative activity
	less than 0.2 more than 0.8
Work according to an individual schedule	Responsibility for the safety of others, personal risk

Emotional stress. In real work conditions, the degree of emotional stress is a significant factor determining the success and reliability of work. Gradations of emotional tension are assessed according to production criteria that create the prerequisites for the occurrence of unfavorable emotional states. These factors will be: 1. Temporal factors (work according to an individual plan, work according to an exact schedule, work under time pressure). 2. Motivational significance of violations in the process of activity (emergency situations, work associated with personal risk, with responsibility for the safety of other persons).

Intellectual tension. The amount of intellectual stress cannot be precisely categorized. The factors that determine it may be: work related to the need to develop algorithms for activities of varying complexity; work related to decision making at various levels; work associated with the need for the participation of a non-standard, creative component of the activity.

The monotony of work. Monotonous types of labor include those that are characterized by the following features: 1) high frequency of repetition of labor actions; 2) short time cycle for performing operations; 3) low-element quantitative composition of the operation; 4) structural uniformity of labor actions; 5) simplicity of labor actions. These criteria relate primarily to work where the leading role is played by the energy factor, i.e. work with a pronounced physical component. Those jobs where the information factor predominates, i.e., stress on sensory mechanisms and certain mental functions are required, are considered monotonous if they: 1) are associated with long-term passive observation; 2) have a lack of sensory information; 3) have limited exposure to production signals and stimuli.

Memory. The load on memory is determined, firstly, by the required amount of memorized information; secondly, with the duration of storage of the necessary information in the process of activity.

Shift work. According to the degree of intensity of the work regime, four categories are distinguished: 1) Work on the morning shift is the most optimal. 2) Evening shift. Work is layered with everyday stress, activity is worse in the evening. 3) Alternation of shift work: morning, evening, night. 4) Round-the-clock work. Three-shift and round-the-clock work is the most tiring and non-physiological.

The labor intensity criteria are given in table. 2.