1. The lecture
Hygienic description of physical, chemical and biological factor of production environment

2. THE PLAN Hazards and their prevention
Noise, it’s influence of human organism in industry.
Vibration , it’s influence of human organism in industry.
Ultraviolet radiation
Dust, it’s influence of human organism in industry
The industrial microclimate. Exposure to heat and cold.

3. HAZARDS AND THEIR PREVENTION
Various external sources, such as chemical, biological, or physical hazards, can cause work-related injury. Hazards may also result from the interaction between worker and environment; these so-called ergonomic hazards can cause physiological or psychological stress.
Chemical hazards can arise from the presence of poisonous or irritating gas, mist in the workplace. Hazard elimination may require the use of alternative and less toxic materials, improved ventilation, leakage control, or protective clothing.
Biological hazards arise from bacteria or viruses transmitted by animals or unclean equipment and tend to occur primarily in the food-processing industry. The source of the contamination must be eliminated or, when that is not possible, protective equipment must be worn.
Common physical hazards include ambient heat, dust, noise, vibration, sudden pressure changes, radiation. Industrial safety engineers attempt to eliminate hazards at their source or to reduce their intensity. If this is impossible, workers are required to wear protective equipment. Depending on the hazard, this equipment may include safety glasses, earplugs or earmuffs, face masks, heat or radiation protection suits, boots, gloves, and helmets. To be effective, however, the protective equipment must be appropriate, properly maintained, and worn by the worker .

4. it’s influence on human organism in industry
Noise,
it’s influence on human organism in industry

5. Noise - "Wrong sound, in the wrong place, at the wrong time.“
Man is living in an increasingly noisy environment. The 20th century has been described as the "Century of Noise". Noise has become a very important 'stress' factor in environment of man.

6. Noise In physics In acoustics noise is a sound vibrations
In information
theory
In physics
In acoustics
a subjective
term
noise is a sound
vibrations
of a different
frequency
and different
loudness
“white” noise
consists of
all audible
frequencies,
just as white
light consists
of all visible
frequencies
the term
designates a
signal that
contains no
information
Noise is
referring to
any
unwanted
sound

7. Properties of Noise 1. FREQUENCY
Human ear can hear frequencies from 16 – Hz.
Infra audible : Sounds below 16 Hz
Ultra sonic : Sounds above 20,000 Hz
On frequency distinguish noise of low frequency (16… 350 Hz), middle-frequency (350… 800 Hz) and high frequency (more than 800 Hz).
 2. LOUDNESS
It is measured in decibels (dB). It depends upon amplitude of vibrations, which initiated noise. A daily exposure up to 85 dB is about the limit people can tolerate without substantial damage to their hearing.

8. Sound intensities are measured in decibels (dB)
Sound intensities are measured in decibels (dB). For example, the intensity at the threshold of hearing is 0 dB, the intensity of whispering is typically about 10 dB, and the intensity of rustling leaves reaches almost 20 dB. Sound intensities are arranged on a logarithmic scale, which means that an increase of 10 dB corresponds to an increase in intensity by a factor of 10. Thus, rustling leaves are about 10 times louder than whispering.
The decibel scale is logarithmic and climbs steeply: An increase of about three decibels is a doubling of sound volume. In the wilderness, a typical sound level would be 35 dB. Speech runs 65 to 70 dB; heavy traffic generates 90 dB. By 140 dB, sound becomes painful to the human ear, but ill effects, including hearing loss, set in at much lower levels.

9. Acceptable Noise Levels
RESIDENTIAL: Bed room dB
Living room dB
COMMERCIAL : Office dB
Conference dB
Restaurants dB
INDUSTRIAL :
Workshop dB
Laboratory dB
EDUCATIONAL: Class room dB
Library dB
HOSPITALS: Wards dB (45dB )

10. The most significant health problem caused by noise pollution is hearing loss . Any noise appreciably louder than talking can damage the delicate hair cells in the cochlea, the structure in the inner ear that converts sound waves into auditory nerve signals.
The initial damage to the cochlea may be temporary, but with repeated exposure, the damage becomes permanent. But even sound levels of only 85 decibels will cause some hearing loss after prolonged exposure. In addition to deafness, many people with damaged ears are afflicted with tinnitus, or ringing in the ears.

11. Deafness,
most simply defined as an inability to hear. This definition, however, gives no real impression of how deafness affects function in society for the hearing-impaired person. Four types of hearing loss may be described. The first, conductive hearing loss, is caused by diseases or obstruction in the outer or middle ear and usually is not severe. A person with a conductive hearing loss generally can be helped by a hearing aid. Often conductive hearing losses can also be corrected through surgical or medical treatment. The second kind of deafness, sensorineural hearing loss, results from damage to the sensory hair cells or the nerves of the inner ear and can range in severity from mild to profound deafness. Such loss occurs in certain sound frequencies more than in others, resulting in distorted sound perceptions even when the sound level is amplified. A hearing aid may not help a person with a sensorineural loss. The third kind, mixed hearing loss, is caused by problems in both the outer or middle ear and the inner ear. Finally, central hearing loss is the result of damage to or impairment of the nerves or nuclei of the central nervous system. Continuous or frequent exposure to noise levels above 85 dB can cause a progressive and eventually severe sensorineural hearing loss.

12. Decibel Scale Decibels (dB) Typical sounds threshold of hearing 10
threshold of hearing 10
quiet whisper 20
average whisper
20-50
quiet conversation
40-45
hotel; theater (between performances)
50-65
loud conversation
65-70
traffic on busy street
65-90
train
75-80
factory (light/medium work) 90
heavy traffic
90-100
thunder
space rocket at take off

13. Industrial Noise
A number of industrial operations generate noise. Stamping metal into auto fenders, punching holes into metal plates, riveting plates together, and crashing different materials all produce impact noise, and grinding and drilling metal produce continuous noise. Rapid air motion caused by jets of air, blowers, and fans, and vibration of equipment also cause noise. Although industrial noise mainly affects workers in the industry, some of this noise also reaches nearby homes.

14. Most hearing loss occurs in workplaces, where workers may be unable to avoid unhealthy noise, and where exposure may continue for years.
Factory workers
musicians
firefighters
construction workers
police officers
farmers
military personnel

15. EFFECTS OF NOISE EXPOSURE
The effects of noise exposure are of two types :
auditory and non-auditory.
1. AUDITORY EFFECTS
Auditory fatigue : It appears in the 90dB region and greatest at 4000 Hz. It may be associated with whistling & buzzing.
Deafness : Temporary deafness appears in frequency range of 4, Hz. It disappears after sometime.
Permanent deafness appears after repeated or continuous exposure to noise around 100 dB. Exposure to noise above 160 dB may rupture tympanic membrane

16.          2. NON - AUDITORY EFFECTS:
a) Interference with speech: Noise interferes with speech communication. The frequencies causing most disturbances to speech lie in Hz range.
b)   Annoyance: This is primarily a psychological response.
c) Efficiency of work: Efficiency of work decreases because there is loss of concentration due to noise.
d)Physiological changes: A number of physiological changes occur due to noise, they are :
•         Increase in blood pressure
•        Increase in intracranial pressure
•         Increase in heart rate
•        Increase in breathing rate
•         Increased sweating
e) General effects
Nausea, vomiting, giddiness and fatigue may also occur. Sleep is also disturbed by noise.

17. a general illness of an organism cardiovascular problems,
Noise makes conversation difficult, interferes with some kinds of work, headache, tiredness, loss of memory and appetite, and disturbs sleep.
Noisy disease is
a general illness of an organism
with such symptoms as
damage of
hearing organ
cardiovascular problems,
high blood pressure
nervous
disorders

18.          Noise Control Methods
Level of noise can be controlled and changed in some ways. Substitution of a quieter machine design, process, or material may be an easy and effective means of eliminating or reducing a noise problem. This principle can be or has been applied in several ways. For example, a low-speed propeller fan makes less noise than a high speed one, and a squirrel cage blower makes less noise than a propeller-type fan. Installing devices that resist motion and thereby damp vibration or using stiffer materials that resist vibration, can reduce noise from vibrating surfaces. Forces that cause vibration can sometimes be isolated by mounting the equipment on springs or resilient materials such as rubber and by using flexible connections. Jet exhausts can be modified to produce less air turbulence, and mufflers reduce noise from engine and air exhausts.
If noise cannot be reduced to acceptable levels in industry, personal protection or special design considerations may be necessary. Fitted earplugs sometimes protect the ear more effectively, but the visibility of earmuffs makes their use easier to supervise. Workers may also be shielded by enclosing or partly enclosing the noisy operations. If reverberation is a problem, surfaces can be treated with sound-absorbing materials that do not reflect sound. In offices and homes, rugs, curtains, and acoustical ceiling materials are used to absorb sound. Because heating and air conditioning ducts provide a part for sound transmission, they can be lined with sound-absorbing material or baffled to reduce noise.

19.          NOISE CONTROL
While noise cannot be totally eliminated, much can be done to reduce it.
1. Control at source : This can be achieved by segregating noisy machines, application of noise mufflers, etc.
2.Control of transmission : This may be achieved by building enclosures and covering room walls with absorbing material.
3.Protection of exposed people : Exposed people must use earplugs. They must be regularly checked and moved from noisy place to quiet place.

20. Vibration , it’s influence of human organism in industry.

21. frequency (Hz) - (one oscillation for one second)
Vibration is characterized by:
frequency (Hz) - (one oscillation for one second)
amplitude (m) - (maximal deviation of body from
position of stable balance)
Its derivatives on time –
vibrospeed (m/sec)
vibroacceleration (m /sec2)
As criteria for hygienic estimation and normalizations of vibration are
applied vibrospeed or vibroacceleration as changes in an organism
under the influence of vibration depend on the quantity of energy of the
fluctuations transmitted to an organism which, in turn, is proportional
to a square of oscillatory speed or oscillatory acceleration.

22. Vibration, especially in the frequency range Hz, may be encountered in work with pneumatic tools, such as drills, hammers, and chisels, in mines, quarries, foundries or the machine industry, or with other machines, such as those used in the shoe industry, and motor saws in forestry.

23. local general Vibration is transferred to hands of the
working at contact
to the vibrating tool
or the equipment
general
Is transferring on a body
of the sitting or worth person
through basic surfaces
(a seat, a floor, a working
platform)

24. Vibration usually affects the hands and arms
Vibration usually affects the hands and arms. After some months or years of exposure, the fine blood vessels of the fingers become increasingly sensitive to spasm, especially after exposure to the cold or to vibration (white fingers). Exposure to vibration may also produce injuries of the joints of the hands, elbows and shoulders. Such symptoms may be very common, e.g., among forestry workers.

25. constant (vibrospeed changes less than 6 dB for 1 minute)
Vibration is
constant (vibrospeed changes less than 6 dB for 1 minute)
changeable (changes of the vibrospeed more than 6 dB for 1 minute)
To changeable vibrations concern:
varying in time (the level of the vibrospeed continuously changes)
faltering (contact of the operator to vibration interrupts and makes more than 1sec)
pulse (one or several vibrating influences by duration less than 1 seс)

26. The prevention of Vibration
The prevention measures of decline of influencing of vibration on an organism include:
technological processes (automation of remote control, creation of machines with vibroisolation facilities)
rational regime of labour (time of contact with vibration makes a 20-30% working change, 2 breaks for active rest)
individual facilities of protection (specific gloves and shoes)
periodic medical control

27. Ultraviolet radiation
In industry workers are affected by ultraviolet rays with the length less than 280 nm.
Occupational exposure to ultraviolet radiation occurs mainly in arc welding. Such radiation mainly affects the eyes, causing intense conjunctivitis and keratitis (welder's flash.) Symptoms are redness of the eyes and pain; these usually disappear in a few days. The welder himself is usually well protected against radiation from his own work. The worker affected by welder's flash will therefore often be found to have been standing next to a welder, and to have been wearing goggles that do not protect the sides of the eyes. No permanent disability appears to result from this occupational disease.

28. it’s influence of human organism in industry

29. Dusts are solid particles generated by handling, crushing, grinding, and disintegrating organic and inorganic materials, such as rocks, ore, metal, coal, wood, and grains. The exposure of man to dusts can lead to a wide variety of respiratory diseases, including pulmonary fibrosis, obstructive lung disease, allergy and lung cancer. Toxic dusts may produce systemic poisoning after inhalation, or act as skin irritants to produce dermatoses, allergic reactions and cancer.

30. Classification of a dust
I. For the origin the dust is divided into three groups:
  1) Organic (-Vegetative: wood, plans, tobacco, cotton, Cane fibre
-Animal: Hay or grain dust);
  2) Inorganic (-Mineral: Quartz, Coal, Silica, Asbestos,
- Metal: Iron and other );
3) Mixed (artificial, plastic).
II. Froom dispersing into two groups:
  1) Aerosol of disintegration
2) Aerosol of condensation
III. For the size:
1)  Visible – the size of speck of dust is more than 10 micrometer,
2)  Microscopic – the size is ,25 micrometer,
3) Ultramicroscopic – the size is less than 0,25 micrometer

31. Dust influences on:
      - System of breath and causes such specific illness -pneumoconiosis, pneumonias, chronic bronchitis,
and not specific illness such us: cancer, tuberculoses;
-        - On skin;
- On eyes.

32. a) Chemical composition b) Size of particle
The hazardous effects of dusts on lungs depends upon a number of factors, such as
a) Chemical composition
b) Size of particle
c) Concentration of dust in air.
d) Period of exposure
e) Health status of workers

33. (plural, pneumoconioses),
Pneumoconiosis
(plural, pneumoconioses),
a general term for any one of several lung diseases caused by breathing dust from industrial occupations like coal mining, sand blasting, and stone cutting.Years of continual exposure to industrial dust can cause the formation of spots (macules), lumps (nodules), or fibrous growths in lung tissue, causing permanent damage or destruction of these tissues. Smoking can complicate or worsen the conditions. Symptoms of the disease include shortness of breath, labored breathing, coughing, and production of phlegm.

34. Forms of pneumoconioses are:
— Anthracosis - Coal dust
— Silicosis Silica
— Asbestosis Asbestos
— Siderosis – Iron
— Bagassosis Cane fibre
-- Byssinosis Cotton dust
— Tobacossis - Tobacco
— Farmer's lung - Hay or grain dust

35. Silicosis
Free silica (SiO2) in the form of quartz, tridymite, or cristobalite, can cause silicosis, whereas silicates do not usually present a significant health hazard. Drilling, crushing, grinding or handling quartz sand produces quartz dust. Occupational exposure occurs in mines and quarries, not only where quartz is mined but also in metal mines where the rock between the veins of ore contains free silica. Exposure may also occur in factories where quartz sand is used, e.g., in steel works and iron foundries, and in the ceramics and glass industries.

36. Dust enters the body by inhalation
Dust enters the body by inhalation. Particles larger than 5 microns in size are generally deposited in the upper respiratory tract and bronchi, and are gradually removed by the ciliary’s epithelium (lung clearance). Smaller particles are deposited in the alveoli of the lungs and then gradually transported to the corresponding lymph nodes. The proportion of the dust that remains in the lungs does so for life, since quartz particles are practically insoluble; connective tissue is then formed around the particles so that nodules are produced. The nodules may gradually aggregate and massive pulmonary fibroses may develop later and progress over a number of years, leading to emphysema with gradual impairment of lung function. Subjective symptoms, which develop rather late, include cough and shortness of breath (dyspnoea) at effort. Silicosis is often combined with tuberculosis. The disease is gradually progressive and death occurs from right heart failure or from pulmonary tuberculosis. It usually takes 15 to 20 years of exposure before symptoms develop. Unprotected workers in occupations with intense exposure to silica, such as sandblasting in confined spaces, tunneling through rock with a high quartz content, and manufacturing abrasive soaps, may develop silicosis in less than a year.

37. Anthracosis
Coal worker's pneumoconiosis, also known as black lung disease or anthracosis, is caused by inhaling coal dust for prolonged periods, usually at least 10 years. Coal worker's pneumoconiosis is much more common in miners of anthracite coal than in miners of bituminous coal.

38. These diseases (Silicosis and anthracosis) are diagnosed when small, irregular, opaque areas are seen on X-ray and people have a history of expo­sure to coal dust or silica. With long-term exposure, these irregular areas become larger and combine into more regular, small, rounded nodules.
However, both coal worker's pneumoconiosis and silicosis may develop into progressive massive fibrosis, also called complicated pneumoconiosis. Only a small percentage of those with coal worker's pneumoconiosis develop massive fibrosis. The mechanism that causes it is unknown. Those with silicosis, however, are likely to develop progressive massive fibrosis.
There is no specific treatment for either of these diseases.

39. Prevention
Prevention is the best course of action. Wear a dust mask and take other steps to prevent exposure to the dust if man is working in an occupation that puts at risk of developing one of these diseases. In addition, do not smoke.

40. ASBESTOS
Symptoms:
•   Chest pain
•   Shortness of breath
•  Decreased exercise tolerance
Cough

41. Asbestos is a mixture of magnesium and iron silicates in fibrous form
Asbestos is a mixture of magnesium and iron silicates in fibrous form. It appears as dust in the form of fine fibres in the air. Asbestos is a general name for a class of natural fibrous hydrated silicates of different chemical composition and with different physical properties, such as range of fibre diameter, flexibility, tensile strength, and surface properties. They consist of % of silica (SiO2) in combination with oxides of iron, magnesium, and other metals. The most important forms are chrysotile (white asbestos, which accounts for 95 % of world production) and the amphiboles, which occur in different varieties, e.g., crocidolite (blue), amosite (brown), and anthophyllite (white).

42. Occupational exposure occurs in asbestos mines and wherever absestos or asbestos products are used, for instance, in handling asbestos-cement products used in the building industry (roofing sheets, wallboard and pipes). Exposure may also occur in the textile industry in the manufacture of fireproof materials, such as asbestos clothes or brake linings for motor vehicles. Asbestos is also used for insulation and fire protection.

43. There has been a very rapid expansion in the use of asbestos
There has been a very rapid expansion in the use of asbestos. In 1924 the world production was tons of chrysotile, 5000 tons of crocidolite, and 3000 tons of amosite; the corresponding figures in 1964 were , , and tons respectively. As there are over a thousand uses of asbestos, the number of occupations in which exposure may occur and the number of possible sources of exposure of the general population are also very large. Asbestos fibres can become airborne during road building, soil tilling, and by erosion and weathering. Air pollution may also result from mining and milling, transportation of asbestos ore and asbestos-containing products, and ventilation of asbestos manufacturing plants. Asbestos cement, floor tiles, heat and electric wire insulation, brake linings, asbestos cloth and paper, pipe and furnace fittings, sprayed fireproofing materials, and paint filters represent sources of environmental pollution of varying importance. Asbestos may be found also in water (asbestos pipes) and in beverages such as beer (asbestos filters). A study of river water showed that asbestos fibers were almost universally present, although in small amounts .

44. The evidence for non-occupational exposure to asbestos is derived from three sources :
(1) Asbestos fibres have been demonstrated in the lungs of persons not occupationally exposed .
(2) Asbestos fibres have been demonstrated in ambient air .
In a few geographical areas, pathological changes regarded as indicating a reaction to asbestos—such as pleural calcification—have been identified in persons with no obvious occupational exposure .
Such evidence was obtained in Finland in the vicinity of asbestos mines; in the German near an asbestos factory; in Bulgaria in rural populations in relation to asbestos in the soil; and in rural districts of Czechoslovakia .

45. Different types of asbestos do not seem to be equally hazardous, and in considering the effects of exposure it is essential to know both the type of asbestos and the circumstances of exposure. It has also been pointed out that the biological effects of asbestos fibres may depend not only on the physical and chemical properties of the fibres themselves, but also on their contamination with other chemical substances and on the smoking habits of the exposed population groups.

46. Asbestosis is an occupational disease.
Asbestosis has been produced experimentally in various animal species such as rats, rabbits, and monkeys. Using quantitative inhalation techniques, have shown that chrysotile produces less fibrosis than an equal dose of amosite or crocidolite; this appears to be due to different rates of elimination. The importance of particle length is not yet quite clear, but some authors have shown that in several species fibrosis of the lung is produced by fine particles or very short fibres.

47. The association of lung cancer with asbestos exposure was first suggested by Lynch & Smith but convincing epidemiological evidence was not provided until Merewether reported 31 cancers of the lung among 235 persons who died of occupationally acquired asbestosis in the United Kingdom between 1924 and Further studies in many countries, including the United Kingdom, the USA, South Africa, Canada, Finland, Australia, the USSR, and Italy have confirmed the association between occupational exposure to asbestos and an excess incidence of bronchogenic cancer. It is difficult to establish whether an increased rate of lung cancer may result from exposures that are insufficient to cause asbestosis, but it is certain that the risk of bronchial cancer is exceptionally high if occupational exposure to asbestos is combined with cigarette smoking . There is no evidence so far that non-occupational exposure to asbestos may increase the risk of lung cancer.

48. asbestosis (a form of interstitial fibrosis or pneumoconiosis),
       Asbestos exposure may cause
asbestosis (a form of interstitial fibrosis or pneumoconiosis),
mesothelioma (a cancer of the lining of the lung or abdomen),
or lung cancer.

49. Pulmonary asbestosis may result when the fibers accumulate around bronchioles, the smallest air passageways. Lungs react to the fibers by covering them, forming small masses of scar tissue. Symptoms appear when the scar tissue causes your lungs to lose their elasticity. The first symptom of asbestosis may be the gradual appearance of shortness of breath on exertion.
Another result of prolonged exposure to asbestos may be the development of pleural plaques around lungs. These areas of thickening of the pleura, the double membrane that surrounds your lungs, usually occur along the lower part of the chest wall or near the diaphragm. The presence of pleural plaques is strong evidence that you have been exposed to asbestos but does not mean that your lungs are impaired unless you have other symptoms or signs.

50. Mesotheliomas, malignant tumors arising from the pleura, are a relatively rare type of cancer. Mesotheliomas may develop 20 to 40 years after the exposure to asbestos fibers and can occur even if the exposure was for only 1 or 2 years or even less. Many persons with mesothelioma have no history of exposure to asbestos. The symptoms include chest pain, gradual appearance of shortness of breath, and weight loss. In about half of those with mesothelioma, the disease spreads, producing tumors in other parts of the body. In other cases, the tumors are limited to the chest. Pleural effusion, the buildup of fluid between the two layers of the pleural membrane, often contributes to shortness of breath and chest pain. The disease usually is fatal within 8 to 14 months; 75 percent of patients with mesothelioma die within a year after diagnosis.

51. Byssinosis
Symptoms: - Chest tightness
Cause: This disease sometimes is found in workers who produce cotton.
Diagnosis
The disease may develop soon after first exposure or after years of working in the industry. You may feel a tightness in your chest toward the end of the day on Monday, the first day after the weekend. At first, the symptoms do not appear during the rest of the week, but in 10 to 25 percent of affected persons the chest tightness gradually begins to persist for several days and eventually throughout the week and into weekend and vacation periods.

52. How Serious is Byssinosis?
Byssinosis generally is not serious. If the disease persists or gets worse, however, it can lead to chronic illness such as emphysema and chronic bronchitis. Thus, you probably should stop working in the industry. When exposure to the fibers stops, the illness will clear up.
Treatment
Bronchodilators and antihistamines help clear up the symptoms.

53. Bagassosis
Caused by: Inhalation of sugarcane dust.
Occupation: Sugar - cane industry.
Clinical symptoms of allergic alveolitis: Breathlessness, Cough, Hemoptysis, Fever, Bronchitis, Impairment of pulmonary functions.
Treatment
Generally, avoiding the irritating dust relieves the symptoms. Drink plenty of liquids and use a non-contaminated humidifier. If necessary, your physician may prescribe a bronchodilator.

54. According to standard, established border permissible concentration dust of air in work's rooms, which depending from character and content in it SiO2.
MAC (maximum admissible concentration ) dust (with free SiO2 ) of air is 1-2 mg/m3,
MAC (maximum admissible concentration ) other dust of air in work's rooms is 10 mg/m3

55. The industrial microclimate

56.          Microclimate of industrial premises consists of meteorological conditions in a working zone, which are defined by the influencing on an organism of the person by combinations of temperature, humidity and speed of movement of air, and also temperatures of environmental surfaces and a thermal irradiation. As a working zone is meant the space limited to protecting designs, in height up to 2 m above a level of a floor or a platform on which there are places constant (more than 50 % working hours or more than 2 hrs continuously) or changeable stay working.

57. Parameters of a microclimate measure
in cold (the daily average temperature of external air +10 °С and is lower) and
in warm (the daily average temperature is higher +10°C)
periods of year within one day in the beginning, middle and the end of a labour shift.

58. At fluctuations of the microclimatic conditions caused by technological or other reasons, measurements are necessary for carrying out (spending) also at the greatest and least sizes of thermal loadings on working. The temperature, relative humidity and speed of movement of air are measured at height of 1.0 m from a floor or a working platform at the works, carried out sitting, and at height of 1.5 m - at the works, carried out standing. Measurements are made unitary on constant and changeable workplaces at their minimal and maximal distance from sources, local heat-production, cooling or moisturizing. For the definition of a difference of temperature of air and speed of air movement on a vertical of a working zone it is necessary to make a selective measurements at the height of 0.1; 1.0 and 1.7 m from a floor or a working platform. Intensity of a thermal irradiation establish in a direction of a maximum of thermal radiation from each of the sources at the height of 0.5, 1.0 and 1.5 m from a floor or a working platform.

59. Exposure to heat and cold
It is known that heat may adversely affect alertness, reaction times, and psychomotor coordination; this would account for a higher accident rate among workers exposed to heat. Accidents are particularly frequent among workers who are not acclimatized .
Important hazards associated with cold work are chilblains, erythro-cyanosis, immersion foot, and frostbite as a result of cutaneous vasoconstriction. General hypothermia is not unusual. Although it has often been claimed that the frequency of rheumatism and bronchopulmonary disease is greater among those engaged in cold work, this has not been conclusively proved.
Both the reduction in the temperature of the hands and the wearing of protective gloves reduce dexterity and therefore increase the risk of mistakes and accidents.

60. Unsatisfactory lighting conditions
The assessment of lighting conditions at work must include not only the light intensity and distribution, but also other characteristics, such as shadows, glare, contrasts, and color.
The levels of illumination needed for the performance of difficult tasks at work have been defined. The desirable quantity of light depends on the fineness of detail and the accuracy required in performance of the task. With regard to the quality of light, many complex factors are involved, such as glare, diffusion of light, direction, uniformity, and distribution.

61. Dim light associated with high visual demands may lead to eye strain and fatigue. Exposure to the dim light of inadequately illuminated work­places, or to the partial darkness of a coal mine for eight hours a day over long periods, can cause both acute and chronic effects on health. The former include headache, eye pain, lachrymation, and congestion around the cornea, particularly if the exposure is associated with eye strain from trying to see small objects. The latter include miner's nystagmus.
Natural daylight appears to be best for visual comfort. Artificial lighting may also fulfil the demands of adequate visual performance, if care is taken to secure proper light distribution and to avoid glare. The latter is an important factor in vision. Distraction from visual tasks and loss of concentration may result from "direct glare" This kind of glare is also associated with discomfort, annoyance, and visual fatigue. Intense direct glare may also result in temporary loss of visual ability, as in the case of drivers exposed to direct intense light from on-coming cars at night.

62. OCCUPATIONAL POISONS

63. LEAD POISONING

64. It is one of the most common industrial diseases
It is one of the most common industrial diseases. Lead is a cumulative poison. When absorbed it is stored in the bones in the form of triple phosphate. Lead is dissolved out of bones by acidosis, especially if food taken by the workers is deficient in calcium, i.e., if it does not contain enough milk and milk products, eggs, green vegetables etc.

65. Mode of entry of lead in organism.
1. Ingestion. By swallowing minute particles of lead through drinking water from lead pipes, which is converted by the hydrochloric acid of the stomach into a soluble chloride of lead.
2. Inhalation. By inhaling dust and fumes of mol­ten lead.
3. By Absorption. Skin absorbs lead particularly when it is mixed with oil, as in paint manufacturing concerns.

66. Occupation involved
The main industrial occupations, in which lead poisoning is liable to occur are mining, refining and smelting of lead, pottery manufacture, electric accumulator works, enameling and paint manufacturing industries, smelting of metals, glass and file cutting, manufacture of lead pipes, lead rubber compounds and plumbing sup­plies such as solders, gun shots manufacture, foundries etc.

67. The symptoms of lead poisoning :
obstinate constipation and colic,
appearance of a blue line on gums,
anemia,
stippling of erythrocytes,
rheumatic pains in muscles and joints,
paralysis especially of extensors (dropped wrist and dropped foot are common).
There may be insomnia, headache, interstitial nephritis, lead insanity.

68. Prevention. Hands and fingernails should be thoroughly cleaned and the mouth rinsed before eating. Workers should not take their food in the work rooms, particularly where there is suspicion of lead particles in the air. Workers should use separate clothing while at work. The workshop should always be kept clean, well ventilated and free from dust by wet cleansing of floors and walls. Arrangement should be made for rapid and complete collection of all fumes and dust which should be conducted to condensing chambers. Since inhalation of lead dust is more dangerous than swallowing it, adequate exhaust ventilation should be compulsorily provided in all dust processes. Sand papering, lead painted surface for obtaining a better finish is dangerous on account of evolution of dust. The use of water-proof sand paper which can be used is therefore recommended for the purpose. Handling of poisonous materials should be reduced to the minimum by substitution of mechanical methods. Women and children being particularly susceptible to lead poisoning should not be employed in lead factories. Pregnant women are liable to abortion and stillbirths. Workmen should take drinks containing minute doses of sulphuric acid and they should take nutritious food with plenty of green leafy vegetables, eggs, milk and milk products (owing to their high calcium content) and avoid taking alcoholic liquors. Workers should undergo medical examination after short periods to detect absorption and appearance of incipient symptoms of lead poisoning. Factories should be provided with a separate cloakroom and a mess-room having adequate washing facilities.

69. and its inorganic compounds in air is 0, 01 mg/m3.
Maximum admitted concentration of lead
and its inorganic compounds in air is 0, 01 mg/m3.

70. Mercury Poisoning

71. Mercury or its compounds are used in the manufacture of barometers, thermometers, vermilion and in trades like bronzing, guilding, in manufacture of electric meters and lamps, felt hats and fur dressings .

72. Mode of entry of mercury in organism:
Respiratory tract

73. Mercury is acutely hazardous as a vapor and in the form of its water-soluble salts, which corrode membranes of the body. Mercury vapor is a more toxic form than liquid mercury because the fumes easily enter and poison the body through inhalation. The fine gray mercury powder, which is easily produced when liquid mercury is agitated with substances such as grease and chalk, is potentially more dangerous than the liquid metal because it is less readily recognized. Short-term, limited contact with mercury can cause acute symptoms such as bleeding gums, vomiting, and stomach pain. Mercury poisoning is potentially fatal and can cause irreversible brain, liver, and kidney damage. Because it is difficult for the body to eliminate, mercury acts as a cumulative poison; it can eventually accumulate in the body to dangerous levels. Chronic mercury poisoning occurs when small amounts of the metal or its fat-soluble salts, particularly methylmercury, are repeatedly ingested, either orally or by absorption through the skin, over a long period of time. Ingestion can occur through contamination of the food chain. Because organic mercury compounds such as dimethylmercury were once widely used, significant quantities of mercury have been found in whales and some species of fish. Concern regarding uncontrolled industrial discharge of mercury into the environment has led to stricter environmental regulations in many countries

74. Symptoms of mercury poisoning are:
stomatitis,
salivation,
foetid breath,
sponginess of gums,
falling out teeth,
anemia,
muscular tremors and paralysis

75. Prevention
Workmen, while working, should wear overalls and respirators. Carious teeth of workers should be extracted. The floor should be made of asphalt and should be designed and sloped in such a way that the spilt mercury is collected easily and effectively. Since metallic mercury vaporizes even at ordinary temperature and produces toxic effects, the work should be conducted in rooms at a temperature below 15.6°C. So far as possible mercury should be kept covered so that the volatilization of mercury may be minimum. Rooms, where dust and fumes are evolved, should be provided with exhaust ventilation. Any vapors may be neutralised by spraying floors with ammonium hydrate solution, if required.

76. Maximum admitted concentration mercury in air of a working zone is 0,01mg/m3.

77. Phosphorus poisoning

78. Phosphorus is used in the manufacture of matchsticks and affects those workers who expose themselves to its fumes. Yellow phosphorus is more poisonous and therefore law forbids its use. The dangers of phosphorus poisoning now are much more from its organic compounds, which are used as insecticides or rodenticides

79. Mode of entry of Phosphorus in organism:
absorbed through the skin
inhalation.

80. Symptoms of Chronic Poisoning:
headache,
loss of appetite,
anemia,
dyspepsia,
hepatitis,
albuminuria,
bronchitis
insomnia.
The long bones become brittle and get liable to fracture; a condition known as fragilitasossium

81. Prevention.
Special attention should be paid to the teeth. Mouth should be washed frequently with an alkaline solution. Turpentine is recommended as an antidote for phosphorus, so it should be inhaled. Work should be done in well ventilated rooms and if possible in open air. Work rooms should be provided with exhaust fans or flues to drive away all fumes of phosphorus.

82. Arsenic Poisoning

83. It occurs in those persons, who either handle arsenical pigments, lead arsenate, paris green, inhale arsenical dust from wall papers or those who mount or cure skins of animals. Arseniuretted and phosphuretted hydrogen are given off from damp ferro-silicon; an impure alloy of iron and silicon, which is used in certain metal­lurgical processes. Arsenic may enter into the system from the dust of its salts by inhalation, direct contact and from arseniuretted hydrogen gas.

84. Symptoms of Arsenic Poisoning
Painful eruptions on the mucous membranes of air and eye passages causing conjunctivitis and edema of eyelids, vomiting, colic with marked diarrhea, painful neuritis and anemia. There may be severe irritation accompanied by acne form or eczematous eruptions on the skin. The salts of metal act as local irritants, particularly around the mouth, nose and armpits.

85. Precautions.
Dyed wallpaper should not be used. The use of arsenic based dyes should be discouraged. The workroom should have suitable condensing chambers. Workers should not take their meals in the workrooms. Automatic packing machinery should be used instead of personal handling of arsenical pigments.

86. (Metal fume Fever). Brass Founder's Ague
It is the term applied to a condition resembling malarious ague, but usually apyrexial, which affect persons who are exposed to the fumes from molten brass or even brass dust. Brass founders suffer from bronchitis, asthma, and a disease called "Brass founder's ague" characterized by rigors, fever, and sweating owing to inhalation of fine metal particles of zinc, magnesium or copper oxides.
The work room should be well ventilated and should be provided with exhaust fans. Females should not be allowed to work in brass works. Protective clothing should be provided to workers.

87. Chromate Poisoning.
Persons engaged in chromium plating and in the manufacture of chromate and bichromate of potassium and sodium suffer from chronic ulcers on knuckles or at the root of nails. Chromate poisoning particularly affects nasal septum of the workers suffering from it.
The preventive measures are frequent cleansing of the premises, provision of local exhaust fans to draw off the mist, careful dressing of abrasions, use of ointments or rubber gloves and wearing of masks. Workers should be provided with facilities for bath and ablution.

88. Poisonous Gases and Fumes.
Carbon dioxide, CO2
2. Carbon Monoxide, CO
3. Carbon Bisulphide, CS2
4. Sulphuretted Hydrogen, H2S.
5. Sulphur Dioxide Poisoning, SO2
6. Arseniuretted Hydrogen or Arsine, AsH3
7. Chlorine (Cl) and Hydrochloric Acid Gas (HCL).
8. Ammonia, NH3
9. Benzene.
10. Aniline.

89. Carbon dioxide CO2
It is given off in the process of fermentation in breweries, aerated water works, limekilns, sewers and. certain chemical plants. It occurs in mines, lime and brick kilns, in deep wells and cells etc. Distressing symptoms arise, if the percentage of carbon dioxide increases more than 7-8%.
Its symptoms are headache, chilliness, and symptoms of dyspnoea, leading to unconsciousness and death. Oxygen inhalation should be resorted to as a remedial measure.

90. Carbon Monoxide CO.
It is a colorless, odorless and tasteless gas produced by the combustion of carbonaceous materials. It causes distressing symptoms if present to the extent of 0.1%, whereas exposure to the gas if present in the strength of 0.4% or more may cause death due to its combination with the hemoglobin of the red blood cells to form a stable compound called carboxyhaemoglobin. It is also found in "after damp" of mines. This gas is usually found in gas works, blast furnaces, coke ovens, cement and brick kilns, soda water manufacture, in motor exhausts and in manufacture of wood charcoal.
This gas is most poisonous and acts on the tissues of the body by preventing oxygen from reaching up to them.

91. Symptoms.
1. Headache
2.Irritability
3.Fatigue
4.Vomiting.
5 Impaired judgment
6. Ringing in car
7. Loss of motor-power
8. Unconsciousness .
Prevention
1. Proper ventilation. 2.Fresh air pipe should open near workers Intending rescuers should wear lifebelts with breathing apparatus.

92. Carbon Bisulphide,
CS2
It is used in the manufacture of waterproofs, as a solvent of fats, coutchouc, India-rubber, phosphorus, sulphur and in the preparation of cellulose for artificial silks. It is very poisonous even in minute doses as air containing one part of gas in one million parts of air (1P.P.M) is considered to be toxic.

93. Symptoms of Poisoning.
These include headache, giddiness, tremors, hysteria, atrophy and fatty degeneration of muscles and connective tissues with loss of fat. It also causes haemolysis. In some cases neuritis or paralysis of muscles occur. There may be mania, or dementia. The patient becomes irritable and there may be frequent attacks of colic accompanied by diarrhoea or acute constipation.

94. Precautions.
Workers should be examined medically once a month. They should not take their meals in work rooms. Carbon bisulphide should be kept in covered vessels and fumes arising from them should be removed by exhaust fans.

95. Sulphuretted Hydrogen,
H2S.
This gas has a peculiar smell of rotten eggs and is dangerous to health even if present in the ratio of %. It is found in chemical works, in cleansing of boilers, in soap factories and in treatment of sulphuric acid to remove traces of arsenic there from. It is sometimes also found in sewers, privies, filth and manure heaps. It is called "Stink damp" in mines, where it is produced due to the decomposition of pyrites.

96.      Symptoms.
These are headache, gastric distur­bances and nausea. When inhaled for longer periods it causes convulsions, paralysis, coma and death. In case of high concentrations, death is sudden and instantaneous. For remediable cares, the measures are artificial respiration and the administration of oxygen.

97. Sulphur Dioxide Poisoning, SO2.
It may occur in those workers, who are engaged in the manufacture of sulphuric acid, process of ore burning and bleaching of cotton.
Symptoms. Suffocation, dyspnoea, coryza, cough, opacity of cornea, cynosis, opacity and convulsions.

98. Arseniuretted Hydrogen or Arsine, AsH3.
This gas is found in chemical and galvansing works. Cases of poisoning have occurred from the action of com­ mercial acids containing arsenic on metals and also during roasting of various metallic ores.
Symptoms. Toxic jaundice or haemolysis may occur. There may be vomiting, haemoglobinuria, haematuria and supression of urine.
Remedial measures are the administration of oxygen and transfusion of blood, together with glucosaline solution and diuretics. Free ventilation should be the rule, in stores containing arseniferous materials. patients with mesothelioma die within a year after diagnosis.

99. Chlorine (Cl) and Hydrochloric Acid Gas (HCL).
These evolve in alkali works, bleaching works, paper mills etc.
Symptoms.
These are spasm of the glottis, cough, dyspnoea, bronchial catarrh, respiratory distress, pneumonia and immediate death due to pulmonary edema. The precautionary measures to be adopted are the maintenance of gas-tight plant, the wearing of masks and routine medical inspection of workers.

100. Chlorine (Cl) and Hydrochloric Acid Gas (HCL).
These evolve in alkali works, bleaching works, paper mills etc.
Symptoms. These are spasm of the glottis, cough, dyspnoea, bronchial catarrh, respiratory distress, pneumonia and immediate death due to pulmonary edema. The precautionary measures to be adopted are the maintenance of gas-tight plant, the wearing of masks and routine medical inspection of workers.

101. Ammonia, NH3.
It is evolved in ammonia works, in the silvering of mirrors, tin-plating, in manufacture of ice, refrigeration plants, etc.
Symptoms. Prolonged inhalation of ammonia causes chronic bronchial catarrh, conjunctivitis, salivation, paroxysmal cough but rarely suffocation and death.

102. Benzene.
It is a coal tar derivative and used in rubber works, dry-cleaning works, manufacture of aniline, etc., and explosive industries. The vapors of the gas may be inhaled and substances like nitrobenzol or trinitrol (T.N.T.) may be absorbed through the skin. Since women are more susceptible to the effects of benzene than men, they should not be employed in these trades

103. Symptoms.
Flushed face, nausea, vomiting, pain in abdomen, giddiness, headache, cyanosis, stupor, coma and death. In chronic cases, fatty degeneration of heart, liver and kidneys is common.
Prevention consists in provision of exhaust ventilation and use of overalls, protective gloves, aprons etc. Since the fumes of benzene are heavier than air, exhaust ducts should be laid below the work level, preferably near the floor. Moreover, scrupulous personal cleanliness should be observed.

104. Aniline.
It is used in the manufacture of dyes. Symptoms. They are due to cumulative action of the aniline on human system. They are eczematous ulcerations, cough, tachycardia, nervous symptoms, insomnia, blindness and malignant disease, drop of bladder. The preventive measures are local exhaust ventilation, mechanical manipulation, periodical medical examination and alteration of employment. Washing facilities should be made use of and protective clothing worn.

105. For prevention of occupational diseases,
measures-on three points are needed
medical,
engineering
legislature

106. Medical measures are:
preplacement examinations i.e., placing the right man for the right job through job analysis and other ergonomics techniques,
periodical examinations for assessments especially for hazardous jobs,
medical care through employee's state insurance, welfare and safety aspects through Factories Act provisions, which include first aid etc.
notification of notifiable and compensable diseases, e.g., aniline poisoning, anthrax, arsenic and lead poisoning etc.
other measures like records maintenance and health education etc.

107. Engineering measures include:
(a) good designing of buildings,
(b) good house keeping, ventilation, safety and welfare provisions as per Factories Act,
(c) mechanization of hazardous processes,
(d) substitution for hazardous processes,
(e) enclosures or wet processing for dusty processes and
(f) protective devices etc

108. Occupational Health in Agriculture

109. While a lot of emphasis is given on occupational health aspects in industries, occupational health aspects of agriculture and associated agro-industries, village, cottage and household industries are often neglected. These aspects are to be covered through Public Health Care (PHC) and its set up. But within the set-ups, some orientation (at least inservice orientation) is needed. In a nutshell the occupational health hazards in agriculture may be stated as
(a) agricultural accidents which may occur in (i) farm operations with simple and/or sophisticated tools, (ii) village home accidents like snake, scorpion and other insects bites or accidents owing to close maintenance of animals etc., and (iii) village terrain accidents owing to underdeveloped roads and rickety means of transport,
(b) heavy exposure risks for problems associated with environmental insanitation, zoonosis and cultural lag, poverty, illiteracy and taboos,

110. (c) hazards of harsh climate and dependence on nature (e. g
(c) hazards of harsh climate and dependence on nature (e.g. floods and draughts) and
(d) hazards of toxic chemicals e.g. (i) acute poisoning from toxic organophosphorus compound (Parathion), nitrated and chlorinated phenols or chlorinated hydrocarbons like dieldrin, endrin etc., (ii) delayed or prolonged effects of alkyl-mercury compounds used for speed dressing organophosphorus insecticides like malathion etc. and (iii) hazards of other pesticides, antibiotics and h6rmonal preparations used for insects and animals. .

111. GENEAL PRINCIPLES OF OCCUPATION DISEASE PREVENTION
Substitution:
Replacement of a harmful agent with a relatively safe substance.
Examples:
(a) Benzene can be substituted with toluene.
(b) Yellow phosphorus of match factories is replaced by safe sesqui-sulphide of phosphorus.
Automation:
Isolation of certain dangerous operations in an enclosure with a view to limit the exposure and then working the apparatus by mechanical or electrical devices to protect the workers from noxious agents.
Suppression at the source:
The dust of silica in foundaries and of lead in storage battery plants can be prevented from pounting the air by wetting the floors.
Artificial and natural ventilation:
Vapours, dusts, fumes and gases can be removed by exhaust pipes or the air of work place may be diluted by improving the general population.
Personal protection:
Protective equipment such as masks, respirators, gloves, overalls goggles, shoes, head and car protective devices should be used.
Workers participation:
Reminding the defaulters by other collegues will be helpful in reducing the case incidence.
General cleanliness: It should be applied to the workers before and after their works.

112.   ”Harmful substances. Classification and the general requirements of safety “ in a basis of classifications should lay such criteria as maximal admitted concentration (MAC), DL50 at introduction of substance in a stomach and drawing on a skin, CL50 for inhalatory receipt, factor of an opportunity of a inhalatory poisoning (FOIP), zone of acute and chronic action:

113. Classification of the chemical hazards
Parametr
norm on a class of danger 1 2 3 4
MAC mg/m3
< 0.1
1.1-10
> 10
DL50 inh mg/kg
< 15
15-150
> 5000
DL50cut mg/kg
< 100
> 50000
Zone of acute action
< 6,0
6,1-18,0
18,1-54
> 54

114. Pesticides are used not only in an agriculture and industry (for prevention of damage and destruction of not metal materials (wooden cross ties etc.) harmful an organism). In system of public health services a lot of pesticides is used for struggle with malaria mosquitoes (insecticides, in particular DDT), for struggle with synantropic organisms (insecticides (ce-ce fly), rodenticides).
By the chemical nature all pesticides are divided on carbohydrogenes, galogenic compounds of aliphatic, alicyclic and aromatic carbohydrogenes, nitrose compounds, amines and salt of quadritic ammonia alcales, spirits, phenols, simple ethers, aldegides, ketones, chinons; aliphatic, alicyclic and aromatic carbonic acids, ariloxyacrilcarbonic acid and their derivative, derivative of coal acids derivative of carbamate, thyo- and dithyocarbamate acids derivative of carbamide and thyocarbamide; thyols, sulphides and sulfons, thyocianates and isothyocianates; derivative by the chamois and sulfuric acid, sulfonic acid and their derivative, derivative of hidrasine and nitrocompounds, organic compounds of mercury, tin, silicon, lead. germanium, organic compounds of phosphorus, compounds of arsenic, antimony, bismuth, iron, borum, heterocyclic compounds. In separated classes it's allocated inorganic pesticides (sulfur and its compounds, compound of copper, galogenes, inorganic phosphorus and others (barium carbonate and barium chloride, tallium sulphate, boric acid, preparations nickel and cobalt etc.) and pesticides, received by biotechnology (antibiotics).

115. The organic compounds of mercury (diethylmercury, ethylmercury (preparations the granozan, mercuran and mercurhexan), ethylmercurphosphate (cerezan-М) etc.) are compounds with high toxity. The cases of mass poisonings with a grain, dressed with mercury-contained fungicides ( , Iraq - about 6500 diseases and 459 fatal cases), the pollution of objects of external environment can be accompanied by cases of illness Minamata (poisoning with cumulated in biological objects, in particular in a fish, organic compounds of mercury). The symptoms of intoxication is occured usually in 3-5 months after beginning of work with preparations of mercury, the basic clinical displays remind clinic of a poisoning with inorganic mercury. As the organic compounds of mercury will penetrate through a hematoencephalic barrier encephalopathy and dementic changes develop at earlier stages of disease.
MAC for mercury-contained pesticides is 0,005 мг/м3.
MAC for chlorophos is 0,5 mg/m3.