INDUSTRIAL HYGIENE Fundamentals of industrial hygiene Updated December

INDUSTRIAL HYGIENE Fundamentals of industrial hygiene Updated December 2010 - Information provided subject to the 'Conditions for Sharing Materials and Advice' -

Objective n To learn about industrial hygiene n To define the subject and scope of industrial hygiene n To understand about occupational exposure limits (OEL) n To learn what occupational diseases are and how to prevent them. n To know what engineering controls can be implemented 2

Industrial hygiene n Definition Industrial Hygiene: (Fundamentals of IH, 4 th edition) “Industrial hygiene is that science and art devoted to the anticipation, recognition, evaluation and control of those environmental factors or stresses arising in or from the workplace that may cause sickness, impaired health and well-being, or significant discomfort among workers or among citizens of the community” (AIHA 1994 -1995 Membership Directory) 3

Industrial Hygiene n Industrial Hygiene is the art and science of the anticipation, recognition, evaluation, and control of environmental health hazards arising in or from the workplace. n Safety = prevention of accidents / incidents IH = prevention of occupational illnesses n 4

Fundamentals of Industrial Hygiene Respect hierarchy of controls Evaluation Control Theoretical assessment of exposure Measurement strategy Monitoring Evaluation results Report Basics IH Identification of risks 5

Fundamentals of Industrial Hygiene Chemical agents • gases & vapors • dust = API & IPI Physical agents • noise & vibration • IR & NIR • climate Biological agents (Ergonomics) • repetition • posture • workforce • bio hazards • fungi • allergens • toxins 6

Chemical Hazards n Dusts n Mists n Fumes n Vapors n Gases 7

Physical Hazards n Noise n Vibrations n Radiation – Ionizing radiation : Alpha-Beta-Gamma – Non-ionizing radiation : UV-light, visible light, infrared, radio waves, microwaves 8

Biological Hazards n Viruses n Fungi or Molds n Bacteria n Plants n Insects n Animals 9

Occupational diseases & IH n Exposure to chemical, physical or biological hazards can cause occupational diseases. n Occupational diseases are acute or chronic (gradual or delayed) reactions and are very diverse. n To avoid occupational diseases the exposure should be prohibited, regulated, restricted, limited or controlled by industrial hygiene practices & IH-programs. 10

Occupational health hazards n n n Immediate or acute reactions, like shortness of breath or nausea, can be caused by a one-time event, (e. g. , a chemical spill) (usually no permanent reactions). Gradual reactions, like asthma or dermatitis (skin rashes), can get worse and persist when there is exposure over longer periods (reactions tend to last for a longer time). Delayed reactions or diseases that take a long time to develop, like lung cancer or loss of hearing, can be caused by long-term exposure. These reactions can be noticed long after the job is over. 11

Occupational diseases can be very diverse; n n n n n Acute poisoning Occupational cancer Chronic poison Interstitial lung disease Skin disease Hearing loss Muscular disorders Lower-back morbidity and trauma of the spine … 12

CHEMICAL HAZARDS

Hazardous substances n Hazardous substances are substances that can have a harmful effect on health n Examples: – Chemicals - organic solvents, acids, pharmaceutical ingredients… – Dust - metal dust, wood dust, flour… – Fumes - welding, soldering… – Fibers - asbestos 14

Hazardous substances can enter the body inhalation dermal ingestion 15

Type of Health Effects Acute effects – immediate reaction Chronic effects – develop over years 16

Toxicity or poisoning Response All substances are toxic, there is not one that is not toxic. The doses is the difference between a poison and a medicine. Paracelsus (1493 -1541) Doses = the intrinsic possibility of a chemical substance to cause irreversible effects into a biological system 17

Potency of Hazardous Substances Snake poison – xx can kill Alcohol xx gives effect Xx leads to liver disease We need xx mg/m 3 to live 18

Describing the hazard We need to know how much of a hazardous substance a worker can breathe without harm This is given by the Occupational Exposure Limit OEL 19

Occupational Exposure Limits The OEL is the concentration in the air to which nearly all workers may be repeatedly exposed day after day without adverse health effects to themselves or their children. Termed Threshold Limit Value TLV by ACGIH (ACGIH is an American organisation for industrial hygiene) 20

Variation of exposure with time Exposure patterns vary Shift durations vary To compare exposures for different situations, we need a reference period 21

OEL reference periods 1. 8 hour reference period –ACGIH descriptor TLV-TWA – The 8 hour TWA exposure to which it is believed that nearly all workers may be repeatedly exposed, day after day, for a working lifetime, without adverse effect 2. 15 minute reference period – called Short Term Exposure Limit (STEL)- The 15 minute TWA exposure that should not be exceeded at any time during a work day, even if the 8 hour TWA is within the TLV-TWA. Exposures (re. 15 mins) above the TLV-TWA but below the TLV-STEL should not occur more than 4 times a day, with 60 minutes at least between successive exposures 3. Ceiling (TLV-C) – the concentration that should not be exceeded during any part of the working exposure 22

Who assigns Occupational Exposure Limits? Who assigns OELs? For common hazardous substances 1. 2. Your national health and safety authority ACGIH (called Threshold Limit Value, TLV) For pharmaceutical ingredients 1. J&J corporate toxicologists 23

ACGIH TLV’s Order from www. acgih. org The OEL set by your health and safety authority and ACGIH might be different USE THE LOWER OEL 24

Examples of OEL’s set by ACGIH (values 2007) Hazardous substance Threshold Limit Value TLV 8 hour 15 minute Isopropyl alcohol 200 ppm 400 ppm Benzene 0. 5 ppm 2. 5 ppm Ammonia 25 ppm 35 ppm - C 0. 1 ppm 10 mg/m 3 - Acrolein Particles not otherwise specified Cobalt 0. 02 mg/m 3 An instantaneous ceiling value that should - not be exceeded Source: ACGIH 2007 25

Concentration Units As mass in unit volume 1 mg /m 3 is 1 mg in a cubic meter 1 m 1 μg /m 3 is 1 μg in a cubic meter 1000 μg /m 3 = 1 mg/m 3 1 m 1 m As the proportion of molecules 1 ppm is one part (molecule) in a million 1 ppb is one part in a billion 1000 ppb = 1 ppm 26

Setting an OEL – what to consider n Sources of information – Animal studies – Pharmaceutical trials These indicate the lowest active dose, or the dose where there is no observed adverse effect n Things that influence the effect on the body – – – Amount you breath in (10 m 3 per day) Body weight How long the chemical stays in the body Amount absorbed by body Any hazardous substances formed in the body 27

Setting an OEL – how it is calculated LAD (mg/kg/day) * BW OEL = -------------------------LAD BW V T SF a% V*T*SF*a lowest active dose body weight (50 kg) volume inhaled air (10 m 3) time, in days, to reach steady state in plasma safety factor absorption (assumed = 100%) 28

Typical Notes given with OEL’s n n If carcinogenic, mutagenic or reproductive toxin Skin: Substances which have the capacity to penetrate intact skin Sensitization: where skin or respiratory sensitization could occur (that is, where intense response occurs to low concentrations after a person has become sensitised) BEI: if a biological exposure index has been recommended for the substance 29

Acceptable Surface Limits n A surface limit is sometimes set. It is helpful : – if there might be significant exposure through the skin – if potent substances might be re-suspended and inhaled – to indicate contamination of surfaces 30

Acceptable Surface Limits Acceptable Surface Limit OEL n n The ASL is the acceptable mass on a specified surface area (typically 10 x 10 cm, the area of palms of hand) Often set at 10 times the OEL for an area of 100 cm 2 Not as frequently used as OEL Not set by ACGIH for any substance 31

What to do with the OEL and ASL… n Compare the results from your exposure monitoring surveys with the OEL to check if the exposure is OK n If you use Respiratory Protection Equipment, compare the calculated exposure inside the mask with the OEL to check if the effective exposure is OK n Compare the measured surface concentration with the ASL to check that surface contamination levels are OK 32

Evaluate exposure by comparing measured TWA exposure with OEL Exposure exceeds OEL Exposure as % of OEL Exposure well below OEL 33

Cumulative effect Exposure to different substances or mixtures = rule of cumulative effect = S Cn / GWn < 1 C 1/GW 1 + C 2/GW 2 + C 3/GW 3 + …. < 1 C 1 … n = measured concentration of the substance in the air GW 1 … n = OEL of the measured substance 34

Odor n Odor = no reliable detection system !! n Some substances have no odor: CO, nitrogen, …! n Substances with the odor level above the OEL ! n For some substances at high air concentrations the odor disappears : Upper odor level H 2 S: 200 ppm n The effect of “odor habituation” ! 35

Risk assessment 36

Risk assessment n The purpose of a risk assessment is to determine the risk posed by a chemical or a chemical product. The assessment of the risks of a chemical as such or in a product, consists of four steps: 1. 2. 3. 4. hazard identification dose-response assessment exposure assessment risk characterization 37

Hazardous substances - identification Processes / activities : n n CHA/PHR (Process Hazard Analysis / Review) = theoretical evaluation of the exposure 38

Hazardous substances - identification Raw materials : n n chemical & toxicological properties user information 39

Evaluation of risks Monitoring workplace: = evaluation exposure at workplace • Stationary / personal • Portable / fixed • Short term / 8 hours Bio monitoring: = effects on individual employee • blood, urine • long function • clinical evaluation 40

Hazardous substances - evaluation n Different measuring principles - gases & vapors: Long term Leak detection Short term Bio monitoring Stationary monitoring 41

Hazardous substances - evaluation n Different measuring principles - dust & solids : Long term Bio monitoring Short term 42

Hazardous substances - identification Installations : control measures n Engineering controls – Closed transfer – Isolators – Compartments – Local & overall ventilation n Administrative controls – Procedures – Safe behavior analyses n Personal protective equipment 43

Engineering control – prevention hierarchy High integrity transfer Isolator technology Closed Transfer Direct Laminar Flow Local ventilation 44

Hierarchy of Controls n Elimination n Substitution n Local / General Ventilation n Contained installations n Administrative Controls n Personal Protective Equipment 45

Hazardous substances - control n Elimination : removing asbestos n Substitution : chloroform, benzene, 1, 2 -DCE n Encapsulation : isolators n Overall & local ventilation n Procedures & instructions (work instructions) n Organizational measures (reduce exposure) n Personal protective equipment 46

BIOLOGICAL HAZARDS

Biological Hazards n 'biological agents` shall mean micro-organisms, including those which have been genetically modified, cell cultures and human endoparasites, which may be able to provoke any infection, allergy or toxicity. n Types of biological hazards : – Viruses (e. g. hepatitis C, yellow fever) – Fungi or Molds – Bacteria (e. g. legionella, salmonella ) – Plants – Insects – Animals 48

Biological hazards n Indicative list of activities with possible exposure to biological hazards : – food production, – activities where there is contact with animals and/or products of animal origin, – health care, including isolation and post mortem units, – clinical, veterinary and diagnostic laboratories, excluding diagnostic microbiological laboratories, – refuse disposal plants, – sewage purification installations. 49

Biological hazards Biological agents are classified into risk groups, according to their level of risk of infection: n n group 1 = unlikely to cause human disease; group 2 = can cause human disease and might be a hazard to workers; it is unlikely to spread to the community; there is usually effective prophylaxis or treatment available; group 3 = can cause severe human disease and present a serious hazard to workers; it may present a risk of spreading to the community, but there is usually effective prophylaxis or treatment available; group 4 = causes severe human disease and is a serious hazard to workers; it may present a high risk of spreading to the community; there is usually no effective prophylaxis or treatment available. 50

Risk prevention n If possible, a harmful biological agent, is to be replaced with a biological agent which, under its conditions of use, is not dangerous or is less dangerous to workers' health, as the case may be, in the present state of knowledge. n Exposure must be prevented. n Prevention measures and requirements are different with respect to the classification of the biological hazard (e. g. Construction of the workplace, registrations of exposures, notification of the Government, training programs, collective protection, …) 51

Risk reduction n The risk of exposure must be reduced to protect the H&S of the workers, in particular by the following measures : – an as low as possible number of workers exposed; – work processes and engineering control measures to avoid or minimize the release of biological agents; – collective protection measures and/or, in addition, individual protection measures; – hygiene measures to prevent or reduce the accidental transfer or release of a biological agent; – use of the biohazard sign; – plans to deal with accidents; – testing, where technically possible, for the presence, outside the primary physical confinement; – means for safe collection, storage and disposal of waste; – arrangements for the safe handling and transport. 52

Hygiene & individual protection n n n No eating or drinking in working areas where there is a risk of contamination by biological agents; Use of appropriate protective clothing or other special clothing; Appropriate and adequate washing and toilet facilities, which may include eye washes and/or skin antiseptics; Protective equipment properly stored in a well-defined place, checked and cleaned, and replaced if needed; Working clothes and protective equipment, must be removed on leaving the work-area and kept separately from other clothing. Working clothing and protective equipment must be decontaminated and cleaned or, if necessary, destroyed. 53

PHYSICAL HAZARDS

NOISE

Noise n Noise is defined as unwanted sound or noise pollution. n Noise is measured in decibels (d. B). An 'A-weighting' sometimes written as 'd. B(A)', is used to measure average noise levels, and a 'Cweighting' or 'd. B(C)', to measure peak, impact or explosive noises. Remember every 3 d. B doubles the noise, so what might seem like small differences in the numbers can be quite significant. n n 56

Noise n To evaluate the noise hazards the physical parameter used as risk predictors are defined as follows: daily noise exposure level (LEX, 8 h) (d. B(A) re. 20 μPa) being the time-weighted average of the noise exposure levels for a nominal 8 -hour working day. 57

Effects of noise n Hearing impairment and hearing disorders n Noise and pregnant workers n Work related stress n Influence on work tasks n Disturbance of speech communication n Noise as a cause of accidents n Other health effects 58

Hearing impairment and hearing disorders = Most important effect of occupational noise n Excessive exposures to noise are probably the most common cause of hearing loss due to damage of the inner ear. In general, prolonged exposure to sound levels > 85 d. B(A) is potentially hazardous although the important factor is the total amount of exposure given by the level and length of exposure time. n Risk of instant, irreversible damage begins at +/- 130– 140 d. B(C) peak level. (explosions, firearm reports, or electric arcs). 59

Noise & health surveillance Health surveillance for hearing damage usually means: n regular hearing checks in controlled conditions; n telling employees about the results of their hearing checks; n keeping health records; n ensuring employees are examined by a doctor where hearing damage is identified. 60

Risk prevention Actions to prevent risks are : n assessment of the risks; n prevention of exposure, including the use of personal hearing protection; n limitation of exposure in accordance with exposure and action levels; n health surveillance; n information, consultation, and training to, with, and of workers. 61

Risk assessment … Assessment of risks arising from exposure to noise should consider : n n n the level, type, and duration of exposure, including any exposure to impulse noise; the exposure limit values and action values; effects of noise on the H&S of workers in ‘risk groups’; effects on workers' H&S resulting from interactions between noise and work-related ototoxic substances, and between noise and vibrations; any indirect effects on workers’ H&S resulting from interactions between noise and warning signals or other sounds; 62

… Risk assessment n information on noise emission provided by manufacturers of work equipment in line with the relevant directives; n the existence of alternative work equipment designed to reduce the noise emission; n the extension of exposure to noise beyond normal working hours under the employer’s responsibility; n information obtained from health surveillance; n the availability of hearing protectors with adequate attenuation characteristics. 63

Risk reduction in practice … The reduction in risks from exposure to noise should take into account: n other working methods that need less exposure to noise; n the choice of suitable work equipment, taking account of the work to be done, emitting the least possible noise; n the design and layout of workplaces and work stations; n adequate information and training to instruct workers to use work equipment correctly in order to reduce their exposure to noise to a minimum; 64

… Risk reduction in practice n noise reduction by technical means: – reducing airborne noise by means such as shields, enclosures, and sound-absorbent coverings; – reducing structure-borne noise by means such as damping or isolation; n appropriate maintenance programs for work equipment, the workplace and workplace systems; n organization of work to reduce noise, by: – limitation of the duration and intensity of the exposure; – appropriate work schedules with adequate rest periods. 65

Organizational & administrative noise control Reduction of noise risks by organizational noise-control measures should consider: n noise emissions as an evaluation factor in a procurement policy; n working methods which generate less noise; n organization of work to reduce noise. The organization of work could limit the duration and intensity of exposure by: n keeping the number of exposed workers to a minimum; n task rotation; n scheduling noisy activities for when fewer workers are exposed; n appropriate work schedules with adequate rest periods. 66

Hearing protection ? n If the risks arising from exposure to noise cannot be prevented by other means; n When technical noise control is ineffective, infeasible or prohibitively expensive; n Individual hearing protectors should be selected to eliminate the risk to hearing, or to reduce the risk to a minimum, or at least to make sure the exposure limit values are not exceeded; n Ensure the wearing of hearing protectors; n Check the effectiveness of the measures taken. 67

Hearing protection Some types of hearing protection devices : n Earplugs : Vinyl, silicone, spun fiberglass, cotton/wax combinations, and closed-cell foam products that are inserted or semi-inserted in the ear canal to form a noise blocking seal. Comparatively, the attenuation is better below 500 Hz and above 2. 000 Hz. n Earmuffs : Ear cups, usually of rigid plastic material with an absorptive liner, that completely enclose the outer ear and seal around it with foam- or fluid-filled cushions. Comparatively, the attenuation is better at intermediate frequencies. n Earmuffs With incorporated active noise cancellation : a new technology that especially for the lower frequency range offers an active noise-level-dependent attenuation, as well as a passive protection. 68

Information and training Workers exposed to noise should receive information and training on the risks of that exposure, in particular: n the nature of such risks; n the measures taken in order to eliminate or minimize the risks; n the exposure limit and exposure action levels; n the results of the assessment and measurement of the noise and an explanation of their significance and potential risks; n the characteristics and properties of the hearing protectors; n the correct use of hearing protectors; n why and how to detect and report signs of hearing damage; n the circumstances in which health surveillance is applicable; n safe working practices to minimize exposure to noise. 69

VIBRATIONS

Vibrations n Vibration is mechanical oscillation about a reference position. n Vibration is an everyday phenomenon, we meet it in our homes, during transport and at work. n Vibration is often a destructive and annoying side effect of a useful process, but is sometimes generated intentionally to perform a task. n For occupational health the exposures to hand-arm vibrations and whole-body vibrations are concerns. 71

Hand-arm vibrations n hand-arm vibration : the mechanical vibration that, when transmitted to the human hand-arm system, entails risks to the health and safety of workers, in particular vascular, bone or joint, neurological or muscular disorders. n The assessment of the exposure is based on the calculation of the daily exposure value normalized to an 8 -hour reference period, expressed as the square root of the sum of the squares (rms) (total value) of the frequency-weighted acceleration values, determined on the orthogonal axes ahwx, ahwy, ahwz. 72

Whole-body vibrations n Whole-body vibration : the mechanical vibration that, when transmitted to the whole body, entails risks to the health and safety of workers, in particular lower-back morbidity and trauma of the spine n The assessment of the exposure to vibration is based on the calculation of daily exposure expressed as equivalent continuous acceleration over an 8 -hour period, calculated as the highest (rms) value, or the highest vibration dose value (VDV) of the frequency-weighted accelerations, determined on three orthogonal axes (1, 4 awx, 1, 4 awy, awz). 73

OEL & action levels Vibrations Hand-arm Whole body OEL 5 m/s² 1, 15 m/s² Action levels 2, 5 m/s² 0, 5 m/s² 74

Reduction program for exposure to vibrations technical and/or organizational measures : n n n n n other working methods that require less exposure; choice of appropriate work equipment of appropriate ergonomic design producing the least possible vibration; the provision of auxiliary equipment that reduces the risk of injuries caused by vibration; appropriate maintenance programs for work equipment, the workplace and workplace systems; the design and layout of workplaces and work stations; adequate information and training to instruct workers; limitation of the duration and intensity of the exposure; appropriate work schedules with adequate rest periods; provision of clothing to protect from cold and damp. 75

RADIATION

Radiation n Ionizing radiation (high energy) : Alpha. Beta-Gamma n Non-ionizing radiation (low energy) : UVlight, visible light, infrared, radio waves, microwaves 77

Radiation; ionizing & non-ionizing 78

Ionizing radiation (high energy) n n Ionizing radiation is transmitted by radioactive materials and certain equipment It can permeate through many materials There are 3 types of ionizing radiation; alpha, beta & gamma radiation Ionizing radiation can have various effects on health; – Radiation sickness occurs after exposure to a very high dose of radiation. It normally leads to death. – Exposure to a moderate dose can lead to radiation tumors. – Other effects are changes in the hereditary material (DNA) like infertility, malformation of the unborn child and cancer. 79

Non-ionizing radiation (low energy) n n Is electromagnetic radiation with a lower frequency. There are different types; – – – n n UV : eg. Welding arcs, lasers, … Visible light : lamps, TL-tubes, welding arcs, lasers, … Infrared : heat lamps, electrical heaters, welding process, … Radio waves : heating, signal transfer, plastic sealing, … Microwaves : electromagnetic waves High exposure levels can heat up the body tissue. Prolonged exposure to low levels could cause health damage, depending on the wavelength, the energy content and the depth of the penetration, like inflammations of the eye, skin burns, tumors or melanomas and reduced fertility. 80

Control measures for radiation n No eating, drinking or smoking at the workplace. n Implement consequent personal hygiene. n Leave the packaging of radioactive material intact. n Do not dismantle radioactive sources. n Use specific personal protective equipment. n Place warning signs. n Cordon off the areas around a radioactive source. 81