- •Introduction
- •Chapter 1 Occupational safety and health legislation
- •1.1. Legislation of occupational safety
- •1.1.1. Occupational safety law
- •1.1.2. Protection of women labor
- •1.1.3. Protection of underage labor
- •1.1.4. Occupational safety financing
- •1.1.5. State standard acts of occupational safety
- •1.1.6. Standard acts of occupational safety in enterprise
- •1.1.7. General duty of care and responsibilities
- •1.1.8. International cooperation in occupational safety
- •1.2. State management of occupational safety
- •1.2.1. Bodies of state management of occupational safety
- •1.2.2. Occupational safety management system
- •1.3. Occupational safety training
- •1.3.1. Occupational safety training
- •1.3.2. Occupational safety instruction. Types of instruction.
- •1.4. State and common supervision of occupational safety
- •1.4.1. State supervision
- •1.4.2. Public supervision of occupational safety
- •1.5. Principles of accident prevention
- •1.5.1. Accident investigation and recording
- •1.5.2. Occupational disease investigation
- •1.5.3. Accident auditing
- •1.5.4. Accident analysis
- •1.5.5. Risk management
- •1.5.5.1. Hazard identification
- •Inspection worksheet
- •1.5.5.2. Risk assessment
- •1.5.5.3. Risk control
- •Chapter 2 Occupational sanitation and hygiene
- •2.1. Work area microclimate
- •2.1.1. Biological effect of microclimate parameters
- •2.1.2. Meteorological standard
- •2.2. Airborne contamination
- •2.2.1. Biological effect of airborne contaminants
- •2.2.2. Airborne contaminant exposure standard
- •2.3. Ventilation systems
- •2.3.1. Natural ventilation
- •2.3.2. Mechanical ventilation
- •2.3.3. Ventilation system requirements
- •2.4. Heating systems
- •2.5. Illumination of work areas
- •2.5.1. Biological effect and technical characteristics
- •2.5.2. Requirements to work area illumination
- •2.5.3. Types of work area illumination
- •2.5.4. Natural illumination
- •2.5.5. Artificial illumination
- •2.5.6. Artificial illumination standard.
- •2.5.7. Artificial illumination prediction methods
- •2.6. Protection from noise and vibration
- •2.6.1. Noise physical characteristics
- •2.6.2. Noise exposure standard
- •2.6.3. Noise control
- •2.6.4. Infra sound
- •2.6.5. Ultra sound
- •2.6.6. Vibration exposure
- •2.6.7. Vibration control
- •Chapter 3 Electrical safety
- •3.1. Biological effect
- •3.2. Types of electric injury
- •3.3. Why electric injury can be fatal
- •3.4. Basic factors resulting in electric injury
- •3.5. Causes of electric injuries
- •3.6. Assessing risk associated with operating power facity
- •3.6.1. Danger in one-phase power line.
- •3.6.2. Danger in three-phase power line with insulated neutral.
- •3.6.3. Danger in three-phase power line with grounded neutral.
- •3.7. Systems of electric injuries prevention
- •3.7.1. Technical protective systems applied for power facilities in normal operation.
- •3.7.2. Technical protective systems applied for power facilities in emergency operation.
- •3.8. Electro-protective equipment
- •3.9. First aid on electric injury
- •Chapter 4 Occupational safety regulations
- •4.1. Protection from atmospheric electricity. Lightning-proof category and zone type
- •4.1.1. Lightning-proof installation
- •4.2. Fire safety systems
- •4.2.1. Fire safety
- •4.2.2. Automatic fire detectors installing.
- •4.3. Safety rules for computer operators
- •4.3.1. Visual overloading.
- •4.3.2. Overexertion of skeletal-muscle system.
- •4.3.3. Skin irritation.
- •4.3.4. Central nervous system lesion.
- •4.3.5. Effecting on reproductive function.
- •4.4. Workplace aesthetic.
- •4.5. Occupational safety standards for computer workplace
- •4.6. Prophylaxis of occupational disease
- •4.6.1. Medical examination
- •4.6.2. Nutrition
- •4.6.3. Psychological relaxation
2.2.2. Airborne contaminant exposure standard
Exposure standards represent airborne concentrations of individual chemical substances which, according to current knowledge, should neither impair the health of nor cause undue discomfort to nearly all workers. Additionally, the exposure standards are believed to guard against narcosis or irritation that could precipitate occupational accidents.
Threshold limit value (TLV) refers to airborne concentrations of substances to which it is believed that nearly all workers may be repeatedly exposed day after day without adverse effect.
There are three categories of exposure standards:
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8-hour time-weighted averages (TWAs)
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Short-Term Exposure Limits (STELs)
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Peak Limitations or Ceiling Values
8-hour time-weighted averages (twas): average airborne concentration of a particular substance when calculated over a normal eight-hour working day, for a five-day working week.
8-Hour TWA exposures are calculated as follows:
TWA = (C1T1 + C2T2 + C3T3 ... + CNTN)/8
where:
C = concentration of contaminant; and
T = incremental exposure time.
Short term exposure limits (stels): Exposures at the STEL should not be longer than 15 minutes and should not be repeated more than four times per day. There should be at least 60 minutes between successive exposures at the STEL It is to avoid both acute and chronic health effects.
Some substances can cause intolerable irritation or other acute effects upon brief overexposure, although the primary toxic effects may be due to long-term exposure through accumulation of substances in the body or through gradual health impairment with repeated exposures. Under these circumstances, exposure should be controlled not to exceed STEL to avoid both acute and chronic health effects.
Peak limitations are concentrations that should not be exceeded even for an instant during any part of the workday.
For some rapidly acting gases or vapours, the averaging of the airborne concentration over an eight-hour period is inappropriate.
These substances may induce acute effects after relatively brief exposure to high concentrations and so the exposure standard for these substances represents a maximum or peak concentration to which workers may be exposed. Examples of gases or vapours with peak limitation exposure standards are hydrogen fluoride, acetic anhydride, n-butyl alcohol, chlorine, ethyl acrylate, ozone and glutaraldehyde.
Airborne contaminants are classified into 4 classes by their TWA:
1st class – extremely hazardous substances with TWA less 0.1 mg/m3 (lead, mercury, ozone);
2nd class – highly hazardous substances with TWA within 0.1 - 1.0 mg/m3 (sulfuric and hydrochloric acid, chlorine, phenol);
3rd class – medium hazardous substances with TWA within 1.1 - 10.0 mg/m3 (toluene, methyl spirit);
4th class – low hazardous substances with TWA greater 10 mg/m3 (ammonia, gasoline, acetone).
Standard may have a letter that points effect to be produced by contaminant being exposed to the person, for example “O” – acute effect; “A” – allergic effect; “K” – carcinogenic effect; “F”- fibrotic effect.
If there’re some multidirectional hazardous substances simultaneously being in the air of the work zone then concentration of everyone shouldn’t exceed correspondent LAC.
Airborne contaminants may force to have either antagonistic or synergistic effects.
In first case they are of multidirectional action, in the second – unidirectional.
Acceptable condition for multidirectional hazards C1TWA1, C2TWA2...
Acceptable condition for unidirectional ones
Variety of sampling methods are used in sampling of gases, vapors and dust:
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express method, based on colorimetry method;
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laboratory method, that implies sampling in work zone with further physical and chemical analysis in laboratory conditions;
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automatic control method using gas analyzers and gas signaling systems.
Class of substance, concentration and hazard of health impact define periodicity of sampling.
To secure workplace atmospheres, which are as free as practicable from hazardous contaminant following control, measures are developed:
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substituting a dangerous substance with one that is not as dangerous;
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improving technology;
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remote control of manufacturing process;
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isolation of manufacturing equipment, using local ventilation;
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normal operation of heating system;
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medical examination of workers working with harmful substances;
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airborne contaminants sampling in the air of work zone;
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using personal protective equipment.