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Theme: Hygienic assessment of occupational hardness and intensity




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24. /Module1. General questions of Hygiene and Ecology/Practical studies/Microclimate ass/RESEARCH OF THE FACTOR OF INFRA-RED RADIATION.doc
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32. /Module1. General questions of Hygiene and Ecology/Practical studies/Water ass/Mannual 2.doc
33. /Module1. General questions of Hygiene and Ecology/Practical studies/Work hardness/hardness and intencity 2.rtf
34. /Module1. General questions of Hygiene and Ecology/Practical studies/ultraviolate/manual.rtf
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Theme: Hygienic assessment of occupational hardness and intensity
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Theme: Hygienic assessment of occupational hardness and intensity.

Topicality of the theme:

It is known physical, mental and operators’ occupational activities. Each of them may lead to fatigue and over fatigue when irrational organized. Therefore working out and application measures for over fatigue prevention is an important and topical problem of modern hygiene. For efficacy this work priority meaning has been becoming methods of an typification and regulation each activity according to it’s physical processes, industrial environment, quality and amount of an industrial load.

The purpose (general): - to be able to determine hardness of physical and intensity of mental as well as operators’ activities.

Specific goals:

To know how:

  1. To interpret physiological difference between physical, mental and operators activities.

  2. To measure physiological indices of workers functional state in process of activities.

  3. To analyze changes of worker’s functional state using regulations and recommendations.

  4. To know how to work out occupational optimization recommendation.

ACADEMIC CONTENT.

Theoretical questions underlining the implementation of purpose full activities.

  1. Notion about labour as an biological and social unity, modern classification.

  2. Physical, mental, operators’ activities, physiological changes under industrial load.

  3. Notion about emotional strain it’s causes.

  4. Notion about capacity for work, basic changes in activity process.

  5. Notion about hardness of physical work, method, of it’s determining.

  6. Notion about intensity of mental as well as operators work, method of it’s determining.

  7. Guidelines of occupational activities optimization.

Basically.

  1. Даценко І.І., Габович Р.Д.Профілактична медицина. Загальна гігієна з основами екології: Навчальний посібник. K.: Здоров’я, 1999.-P. 452 – 459.

  2. Даценко І.І., Денисюк О.Б., Долошицький С.Л. Загальна гігієна, посібник для практичних занять.-Львів: Світ, 2001.- P. 78-84.

  3. Lecture of the theme.

  4. Department manual.

5. Graph of logical structure of the theme (sup. 1).

Supplementary:

  1. Габович Р.Д., Познанский С.С., Шахбазян Г.Х. Гигиена. - К.: Вища школа, 1983.

  • P.189- 200.


Oriented bases for activities.

After mastering the above problems acquaint yourself with algorithms, which will allow you to muster professional skills in more successful.

To check knowledge of the given material do the following tasks.

Teaching type tasks:

The task 1.

Select most accurate index which hardness of work characterizing among miners as:

  1. Pulse rate.

  2. Blood pressure.

  3. Energy expenditure.

  4. Sensory information quantity.

  5. Sensor information quality.



The task 2.


Select most accurate index which intensity of work characterizing among operators at nuclear power plant as:

1. Pulse rate.

2. Blood pressure.

  1. Energy expenditure.

  2. Sensory information quantity.

  3. Sensor information quality



The task 3.

Most meaning difference between physical and mental activities is shown as:

  1. Speed of industrial fatigue development.

  2. Industrial analyzers strain

  3. Responsibility level for industrial result

  4. Oxygen providing functions strain.

  5. Work shifts presence.



The task 4.

Emotional strain level of pilots most depends on as:

1. Speed of industrial fatigue development.

2. Industrial analyzers strain

3. Responsibility level for industrial result

4. Oxygen providing functions strain.

5. Work shifts presence.


The task 5.

Select priority measure for over fatigue prevention for steel production operators as:

  1. Automation.

  2. Ventilation.

  3. Pre-placement examination

  4. Hazard control.

  5. Respirator.

Keys: 1-3; 2-4.


Concise methodical recommendations for a study .

The students’ independent work includes determining occupational hardness and intensity. Students mastering professional skill by natural experiment organization and teaching situational task solution. Works of 2-3 students are analyzed and generalized at final work part discussion. The final test control over the theme is carried out.


Technological chart of the practical study.






Stages

Time,

Min.

Teaching aids used at classes , location and characteristic of study

A site and character of occupation

1.


2.

2.1


2.2.


2.3.


2. 4.

2. 5.


3.


4.


Checking and correction base line level.


Independent work:

Measure initial functional state level among 4 students

Mental work modeling doing situational problems.

Measure students’ functional state after mental work.

Physical work modeling

Measure students’ functional state after physical.

Analysis and correction of conclusions

The final test control and determining the assessment of study outcome

15


40


60


30

20


30

15


27

Test tasks, educational tables, graph of logical structure, algorithms, physiological apparatuses, situational tasks.

Laboratory of the department, seminar-pract.



Sup.1

Graph of logical structure of the theme

Hygienic assessment of occupational hardness and intensity.


Sup.2


Common preliminary assessment of work hardness ( by pulse rate)

Under 90 beats per min. – easy work

91-100 beats per min - moderate work

101-120 beats per min - hard work

More 120 beats per min - sharply hard work

Preliminary assessment of work intensity ( by pulse rate)

Under 80 beats per min. – law intensity work

81-95 beats per min. – moderate intensity work

96-110 beats per min. – intensity work

111 and more beats per min - sharply intensity work


Sup.3

Direction for independent work in physiological study


1.All students would divide on two subgroups: A. Investigators. B. Investigated. (number of them depends on students quantity in group).

2. Investigators should measure physiological indices of investigated in strict succession:

2. 1. Pulse rate (PL). Investigated is seating (for orthostatic reflex excluding) and investigator measure pulse rate for 15 seconds and result is multiplied to 4 (per minute);

2. 2. Blood pressure (BP). It’s known.

2. 3. Muscular strength (MS). It is done by special apparatus called hand dynamometer.

2.3.1. Investigated seat to table, right hand on the table in position of 120-130 o to the body frontal axis . He gripes with the utmost two time of dynamometer handles, best result (in kg) is considered as meaning.

2. 4. Muscle endurance to static effort (MESE). Criteria for determining this index takes result by 2.3.1. This number divided to 2 (50%) and for investigated directs fulfillment to hold this effort as long as possible. The time during which investigated has been held given effort called as muscle endurance to static effort, in sec.

For example. Investigated has been done test by 2.3.1. by the effort 40 kg. Investigator should calculate limits of static effort as 40 : 2=20kg. But construction of the apparatus excludes observation for apparatus pointer. That’s why investigator determines limits of static effort and provides feed-back for investigated. Take correction factor as 10%. For our sample limits of static effort would be from 20-2 till 20+2 =18=24 kg. When investigated reaches to 24 kg should be informed “Easily”, when to 18 kg – “More”. In case pointer crosses below limit of apparatus dial the time stopped.

2. 5. Focus attention test (FAT), Platonove’s test. FAT do using black and red color figures located in random sequence. Look at the proper table. You see 25 black figures and 24 red one. Direction for investigated should be “You should point alternately red figures in ascending order but black figures in descending one.

For example 1- red, 25 – black; 2 red - 24 black; 3 red -23 black; 4 red -22 black till red will become 24 and black - 1. Because investigated has no experience first measure of time is training but second is meaning for analyze.



  1. All results should be put in table in part “ Operative rest”




Functional state indices

Operative rest

After mental load

After physical load

Investigated A

Investigated B


A


B


A


B

PL per /min



















BP mm. MP



















MS kg



















MESE sec



















FAT sec






















  1. In 60 min. all students should do mental work and after that all measures are repeated and data put in table in column “After mental load”.

  2. In 20 min. investigated students should do different physical work and after that data put in table in column “ After physical load”.

  3. After all measures students make a doctor conclusion. In conclusion should be analyzed:

6.1. Principal difference in change of physiological indices between mental and physical work.

6.2. Determining of a capacity for work stage.

6.3. Previously determining the hardness of physical work (see sup)

6.4. Previously determining the intensity of mental work (see sup)


Supl. 4

Official table for hardness of physical work detemining





N


Indices of production process hardness


Occupational hazard class

Optimal

Tolerance

Dangerous

1 level

2 level

3 level

1

2

3

4

5

6

7

1.

Physical dynamic load

1.1.

By regional load (there are in participant of hands and shoulder girdle muscles previously )
















1.2.

By total load (there are in participant of hands, body, feet )
















2.

Moving load weight ,kg

2.1.

Lifting and shifting of loads alternate to other work
















2.2.

Constant lifting and shifting of loads during work shift

-for men

-for women
















2.3.

Summarized load weighty moving during total shift

A)out of work space,kg

-for men

-for women

B)out of floor

-for men

-for women


















3.

Stereotype work movements

3.1.

By regional load (there are in participant of hands and shoulder girdle muscles previously )
















1

2

3

4

5

6

7

3.2.

By local load (there are in participant of hands and arms muscles previously )
















4.

Work posture

Free, comfortable

Being periodically at uncomfortable, fixed posture under 25% of shift

Being periodically at uncomfortable, fixed posture under 50% of shift

Being periodically at uncomfortable, fixed posture more the 50% of shift




6.

Body inclinations
















7.

Movements in workspace


















Sup. 5

Official table for intensity of operators’ work determining


N

Indices of production process intensity


Occupational hazard class

Optimal

Tolerance

Intensity of work

1 level

2 level

3 level

1

2

3

4

5

6

7

1.

Intellectual load

1.1.

Work content




Elementary

and alternative tasks according to an instruction solution

Difficult with alternates tasks of known algorithm solution

Heuristic activity (creative) which require difficult tasks solution




1.2.

Signal perception

Signal perception without correction

Signal perception with action correction

Signal perception, with previously comparison and their assessment

Signal perception with assessment interrelated parameters




1.3.

Complexity of an output programme

Working and fulfillment of instruction

Working and fulfillment of instruction and result control

Working and control of fulfilled task

Control and previous work in tasks distribution to other workers




1.4.

Character of an output programme

Work according to individual plan

Work according to schedule and it’s correction

Work in time deficiency

Work in time deficiency and responsible information




2.

Sensor loads

2.1.

Rapt attention duration (percentage to sift)
















2.2.

Signal compactness
















2.3.

Number of simultaneous observation objects
















2.4.

Load on visual analyzer

-observation to video display (hour per shift)
















2.5.

Load on auditory analyzer

















1

2

3

4

5

6

7

3.

Emotional load

3.1.

Responsibility level. Mistake importance

Responsible for fulfillment of some elements.

Responsible for functional quality of auxiliary fulfillments

Responsible for functional quality of basic fulfillments

Responsible for functional quality of final fulfillments




3.2.

Risk level for own life
















3.2.

Risk level for other persons safety



















Monotony of load

4.1.

Number of elements necessary for doing elementary fulfillment or in repeated actions


















The brief contents of theoretical questions

Occupational hygiene is essential branch of hygiene. Other side occupational hygiene is a branch of the occupational medicine. The joint committee (ke’miti) on Occupational health, in the course of its first session, held in 1950, gave the following definition: “occupational health should aim at the promotion and maintenance of the highest degree of physical, mental and social well-being of workers in all occupations; the prevention among workers of departures from health caused by their working conditions; the protection of workers in their employment from risks resulting from factors adverse to health; the placing and maintenance of the worker in an occupational environment adapted to his physiological and psychological equipment, and, to summarize, the adaptation of work to man and each man to his job. The terms as “industrial hygiene” or “industrial health” were in vogue (veug). Modern concepts of occupational health now embrace all types of employment including mercantile and commercial enterprises, service trades, forestry and agriculture and include the subjects of industrial hygiene, industrial diseases, industrial accidents, toxicology in relation to industrial hazards, industrial rehabilitation (riebili’tation ) and occupational psychology. Occupational health in agriculture and ergonomics ( human engineering ) are relatively new concepts.

Ergonomics is now a well recognized discipline and constitutes an integral part of any advanced occupational health service. The term “ergonomics” is derived the Greek ergon, meaning work and nomos, meaning law. It simply means : “ fitting the job to the worker ”. Training in ergonomics involves designing of machines, tools, equipment and manufacturing processes, lay-out of the places methods of work and environment in order to achieve greater efficiency of both man and machine. The object of ergonomics is “ to achieve the best mutual of man and his work, for the improvement of human efficiency and well-being”. The application of ergonomics has made a significant contribution to reducing industrial accidents and to the overall health and efficiency of the workers.

Nowadays, in state-of-the-art manufacture conditions, there is certain complex of factors that affects human. From one side, it is physical, chemical, biological factors and dust. From the other side, it is psychological factors: excess or poor movement activity (hyperkinesias or hyperkinesias), excess or insufficiency of muscle exertion (hyperdynamia or hypodynamia), forced body position, forced work pose, monotony (menotni) of work processes, neural-emotional exertion, analyzer load, etc. The influence of psycho-physiological factors, which involve the peculiarity of the work process, can be the cause of serious functional disorders in an organism and formation of the pathology.

It is necessary to notice, that psycho-physiological factors can influence not only on manufacture, but also beyond its bounds. Therefore, the doctor must be able to identify the influence consequences of these factors, give hygienic assessment and work out of disease prevention plan.


In general, there are three kinds of work in modern professions: physical activity, mental activity and neuro-emotional activity. These forms of activity can cause injurious affects on various organs and morpho-functional systems. This effect may be related, whether dominates of muscle activity, or with the load dominates on the central nervous system (CNS). Total assessment of occupation activity on the organism can be given using categories (‘ketegri) of work hardness and intensity .

Hardness of work – the characteristic of human work activity, which determines the level of impact on the muscle work and displays physiological expenditure due to physical load. It is characterized by Physical dynamic load, moving load weight, Stereotype (‘stierietaip) work movements, Work posture, Body inclinations, Movements in workspace

Work intensity – the characteristic of work process, which shows the prevalence impact on the CNS. It is characterized by Intellectual or mental load, Sensor loads, Emotional load, Monotony of load, work shift.

When determine the level of work hardness, the assessment is given:

  • Physical dynamic impact according to figures: the amount of lifted weight, distance on which the weight is moved; the frequency of elevations and the weight movement.

  • The quantity of repeated movements (stereotype work motions)

  • Static load during the weight or tool retention. Also, during the holding of body posture and its regions, that depends on the work pose and can be evaluated according to the duration of stay in uncomfortable, fixed position.

  • The number of body inclinations

  • The distance, which a person has to walk during the shift (crossings, caused by technological process)



When determine the level of work intensity, the evaluation is given:

  • Intellectual load: work content, difficulty of an assignment, deficiency of time for making a decision and responsibility for the result of occupation.

  • Sensory load: the duration of concentration, the quantity of simultaneously observed objects, visual analyzer load (size of the observed object, distance and duration of the observation, work with optical devices – microscope, magnifier (megnifaier), etc., the duration of the monitor observation) and the auditory analyzer (manufacturing perception of the voice or signals differentiation);

  • Emotional load: degree of responsibility and risk for own safety or safety of other people;

  • Monotony of the load: the amount of frequently repeated operations and duration of accomplishment (выполнение задания)

  • Work procedure: interchangeability of assignments, irregularity of shifts, nighttime work.


The study of hygienic work procedure is made by timing observations. The number of movements, work motions, work operations are calculated and time of its completion is registered.


When evaluating the influence of work on human, it is necessary to evaluate functional condition of organs and systems. Different methods are used. During the research, the preference is given to morphologic-functional processes with the most expressed and adequate to the load changes.

Musculoskeletal, cardiovascular and respiratory systems adequately react on the impact of the physical load.

During the intensive movements, there is an increase in intensity of biological processes in the working muscle. There is an increase of the functional muscle activity. The intensity and the duration of the increase of muscle activity depends on the load intensity, the specialty of the organism in general and the muscle endurance in particular. The functional reserves of the muscle and the intensity of the biological processes gradually run low. After the work stoppage, the decrease runs as long as the initial level will be reached.

Capacity for work it is a human’s state determining by his/her physiological and psychological resources which characterizing ability to do concrete work given value and quality within given period.



Such specialties of the dynamics of biological processes intensity involve during the static work, muscle exertion occurs without changes in length and without active displacement of the limbs and the whole body. At the same time, contracted muscle fibers squeeze vessels. As a result, muscle blood flow is obstructed and the oxygen consumption is decreased. To all purposes, there is change-over to anaerobic energetic supplying with the accumulation of extensive amount of lactic acid and other metabolic products in muscle.

Essential specialty of the static work is minor increase in oxygen consumption during the static exertion. However, the oxygen consumption and the blood flow are abruptly ( ebrapli )increased immediately after the static work stoppage (Lingard’s phenomen). In number of cases, other physiological indices (pulse rate, respiratory rate etc.) increase after the static load in much higher extent, then during the work on the initial level. The muscle fatigue in addition with insufficient blood circulation over prolonged muscle exertion can lead to muscle diseases and diseases of peripheral nervous system.



It is necessary to strengthen the blood supply of the muscle for the supply of the proper intensity of the biological processes of the static load. It reaches by the increase of arterial blood pressure and pulse rate. Gaseous (gesies) metabolism is increased due to the increase in load intensity. It expresses in increase of respiratory rate and depth, pulmonary ventilation volume. The increase of the erythrocytes resulted from spleen constriction.

Overstrain of the organs and systems can be the reason of the pathology during the physical work. Blood congestion in the lower part of the body leads to varicose veins during the prolonged load in the upright position and during the static muscle exertion. The load on the cardio-vascular system during the physical load can be the reason of the hypertonic disease, ischemic disease of the heart and other cardiac decompensation diseases.



Pic. 3. The dynamics of the work efficiency during the work day. (I, V – produce period; II, VI – period of high work efficiency; III, VII – decrease in work efficiency period; IV – time for lunch brake.


The significant role among professional diseases plays the pathology of the musculoskeletal system, conditioned by overexertion and microtraumatization: periarthritis of the shoulder joint, epycondilitis of the joint, bursitis, ligamentosis, tendovaginitis etc. Static muscle load directed to maintain the work pose can be the reason of the myositis (neuromyositis), upcoming in the result of the biological process disturbance in the muscle tissue. Ailing muscle hardenings (myogelosis) can appear. Inflammatory process can be localized in muscle attaching areas and in periosteum – myositis and aseptic periostitis, with often complications after a cold.


The most acute changes under the mental load, without neuro-emotional exertion, localize in nervous system, analyzers and cardiovascular system.

There is an increase of the intensity of biological processes in nervous system during the mental strain. Energy requirement of the brain increases up to 15-20% of general volume of the biological processes, when the weight of the brain is only 2% of the body mass. The oxygen consumption of the cerebral cortex (100 grams) is 5-6 times more, then required for 100 grams of skeletal muscle during the physical load with maximal intensity.

The poor movement activity does not give physiological basis for tachypnoe like during the physical load. Therefore, cerebral supply in required amount of the oxygen is accomplished by doing one deep inspiration or more often, a few breathes with short gaps in time. This is the oscillation act. Its physiological meaning is that facial and neck muscles constricts during the deep breath by mouth (chewing muscles are the strongest muscles of the body), the intensification of the blood flow in facial muscles improves the blood supply of the cerebrum, as the connections among the facial and cerebral vessels are very short.

Often the mind work is accompanied by the stress impact and other factors that form neuro-emotional exertion: monotony, sameness of moves, difficulty of exercise and responsibility for its completion, hypodynamics and hypokinesia in conjunction with the required work pose, presence of hard operation algorithm, etc.

Neuro-emotional strain leads to the intensification of cardiovascular and respiratory systems activity, the biological process intensity, muscle tone can increase. Tachycardia, an increase of arterial blood pressure, the change in electrical cardiac activity (detected during electrocardiography), an increase of pulmonary ventilation and oxygen consumption, body temperature increase (during expressed and long exertion) and other changes of vegetative functions can be observed during neuro-emotional strain , related with the mind work. The impact of psycho-physiological factors typical for work process during brain work, especially in addition with neuro-emotional work, can lead to development of disease.

Overstrain of nervous system can be the reason of neurosis (information neurosis). Professionals recognize coordination neurosis (professional diskinesia, for example, graphospasm). These diseases are connected with carrying out coordinated movements, often repeated movements, which involve the intense of different muscle groups.

Blood congestion in lower part of the body can lead to varicose veins during standing and sitting position work for long period of time.

Usually cardiovascular pathology during mental work is a result of joint effect of neuro-emotional exertion, hypodynamia and hypokinesia. It is necessary to highlight, that often regulation disoders of hemodymanics are formed. Therefore, the diagnosis ”neurocirculatory dystonia” is input into the medical card.

Work load can be evaluated by the load determination criterion and the intensity of work. The capacity for work is evaluated according to figure changes of the functional condition of the organism. Work efficiency is an ability of person to carry out the load. Given definition is most simple and most exact among 60 known definitions at the present time. Moreover, the ability to carry out the load is a level of functional abilities of the organism, which depends on industrial environment, health condition, age, professionalism level , motivation to work and many other factors.

Carrying out the work, the functional activity and functional abilities of the organism appropriately change during the shift.

Capacity for work changes during the work shift have several phases or replacing each other conditions.

First phase of capacity for work is a development one or increase of the work efficiency. In this period, the lability and the volume of the physiological processes are increased. Comparing with the initial point, the level of the work efficiency is gradually increasing. It appears as an increase in psycho-physiological figures and work results. Depending on the type of work and individual peculiarities of human body, this period lasts from several minutes till 1,5 hrs; and throughout mental work – till 2-2,5 hrs. The second period is a high level of capacity for work . It is typical for this period, the combination of high work indices with relative stability or, even, some minor exertion decrease of the physiological functions. The duration of the stable work efficiency phase can be 2-2,5 hours and more, depending on the level of neuro-emotional strain , physical load and hygienic conditions of work.

Third phase is a decrease of capacity for work . Decrease in work efficiency is accompanied by the decrease of the functional abilities of the main working systems of organism. The decrease in work efficiency before the lunch brake is shown as worsening of the cardiovascular system condition, the increase of reflexes time, decrease of attention, appearance of unnecessary moves, mistaken reactions, and deceleration of time to solve the task.

The dynamics of the work efficiency is repeated after the lunch brake. At this time, the phase of produce is faster, but the phase of stable work efficiency is longer and a level lower then before lunch. The decrease in work efficiency begins sooner in the second part of the shift, and develops faster, because of the more profound tiredness.

The decrease in work efficiency is more or less related with fatigue.

Fatigue is a condition accompanied by the sense of weariness, decrease in work efficiency, caused by an intensive and prolonged activity, and expressed in worsening of quantitative and qualitative indices of work, which stop after the brake.

For a long time, physiologists have been trying to give the answer regarding the essence and the mechanism of fatigue. Fatigue has been considered as a result of energy ”exhaustion” of the muscle resources (mostly carbohydrate metabolism) or as a result of insufficient oxygen supply and oxidizing process derangement – ”strangulation” theory, or has been defined as a consequence of tissue saturation by metabolic substances (”poisoning”). According to one theory, fatigue is related with accumulation of lactic acid in muscles.

All these theories are humoral-localistic, defining fatigue as a process occurred in muscles only. They have not taken into consideration the coordinative role of the CNS.

Nowadays, the most popular is central-nerve theory of fatigue . However, there is no universally recognized theory that will define this effect in all its diversity.

Modern conception of central-nerve fatigue theory does not eliminate possible influence on the formation of tiredness processes (deficit of oxygen, nutrients exhaustion, metabolites accumulation, etc.) by local processes, which occur in muscles and other working tissues. They can accelerate fatigue, and change the functional condition of the CNS by the inverse connections. Anyway, fatigue is a solid process that is expressed in physiological mechanisms of work efficiency limitation.

Physiological picture of physical and mental fatigue is similar. Mental and physical tiredness can provide common impact. In this way, mental work during hard physical tiredness is unproductive, and vice verse, muscle work efficiency is decreased during mental tiredness. These occurrences are caused by irradiation of inhibition from most tired centers to adjacent (e’dgeisent). Elements of muscle fatigue are constantly observed during mental load: long stay in a certain pose leads to considerably expressed tiredness of proper sections of locomotors apparatus.

Significant emotional strain , accompanied by different reactions of vegetative nerve system, is observed under mental fatigue, often under physical tiredness.

Resume of work under developing tiredness brings to accumulation of previous tiredness. Tiredness(fatigue) turns into over fatigue. Headache, sense of heaviness in the head, distraction memory and attention derangement, sleep disturbance are observed under over fatigue.

Carrying out high intensity work under over fatigue, can be the reason of the pathology.


It is necessary to highlight, that phase of stable work efficiency after mental activity is much longer (sometimes 10-11 hours), and it is related with low intensity brainwork compared to physical work. Given feature allows maintaining a high level of functional activity, but in this case, the probability of fatigue is much higher.

Different methods, which can determine the condition of organs, systems and their functional capability, can be used for the evaluation of the work influence on the organism and for study the dynamics of capacity for work. Physiological and psychological indices are examined during the research before and after the work: arterial blood pressure and pulse rate, memory volume, concentration and change-over of attention, information processing speed, visual-motor and acoustic-motor reactions, coordination of movements and tremor of the upper limbs, muscle strength and staying power to static muscle efforts. Nowadays, the research of electric brain activity (electroencephalography and etc.) is widely used. Electrocardiography is very informative. Depending on the research task, there can be used methods which will allow determining the change in intensity of the metabolism, gaseous metabolism, biochemical figures, blood fulfillment of organs, and other methods used for clinical researches.

Using the method of the self-appraisal of the functional condition can give important information.

It is necessary to use arrangements directed on the prevention of early fatigue and prophylaxis of fatigue for the pathology prophylaxis connected with negative impact of the work process.

The most effective method for workers occupied by the physical work is automation and mechanization of work operations, which allows decreasing the weight of the load due to the decrease of the muscle load.

Using rational regimens of work and rest is an effective arrangement. At the same time, there is an even allocation of brakes in the budget of interchangeable time, fulfillment of brakes. Therefore, a worker has to have possibility to spend the brake time in a special room (for example, recreation room), not at the work place.

Moreover, the organization of the work place is very important, not only with the regard of work type, but also with the regard of the usage of manufacture important elements (control lever, source of the information, instruments, etc.). The most significant and most frequently used elements must be located on the work surface in such way, that there will be no difficulties during the work process. Generally, it is a central part of the worktable, machine, control panel, etc. It is called an optimal reach zone. There are less significant objects in the permitted reach zone used rarely during the work. Objects rarely and episodically used (levers, on/off machine switches, etc.) can be placed beyond the optimal and permitted reach zone.

Work tiresomeness and the time of fatigue development essentially decrease the perfection of the professional skills. The last feature has to be brought to automatism. The elaboration of the dynamic stereotype is carried out by multiple repetitions of moves, manipulations, informative signals and etc. during education, exercise and training.

The prolongation of the stable work efficiency phase is attained due to change-over to the different kind of work, switching the load on the different groups of muscles and etc., for the irritation displacement on the areas of the cerebrum that are not enabled in the work. Well known fact, that an addition of the physical exercises to work and rest regimens is effective during brain work, and switching the work hand while doing a long work (for example, putting the load from one hand to another when moving it on a long distance) is effective during the physical load.

Considerable effect can be gained using different interior elements for the psycho-emotional impact on the human condition. These methods provide the usage of the basics of work hygiene, engineering psychology and ergonomics. As is well known, the design of the manufacture equipment makes an impact on the human relation to the surrounding atmosphere. Taking into consideration neuro-emotional load, the necessity of concentration and switching of the attention, the similarity of the work procedures, colored design of the manufacture facilities is widely used. The basic of this is the usage of the color scale: red, orange, yellow, green, pale and dark blue, violet. Green is a neutral, yellow is lightly restorative, pale blue is lightly relaxing. Red and orange are irritating colors; dark blue and violet are inhibitory. Different tints can be used for more precise elective impact on the functional condition of the CNS.

Moreover, there are enough resources for the increase of the work efficiency. These are specially selected physical exercises, massage, emotionally volitional control of the condition, functional music and etc.

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