CHAPTER 4. PREPRODUCTION Preproduction involves constructing the sets and props. They can be made in permanent scene shops or studios and then transported to the filming site, or actually constructed on site. They can consist of full-scale sets or miniature models for special effects filming. CARPENTRY Constructing sets from wood can involve the use of various woods, plywood, particle board, and plexiglas. A variety of hand and power tools are employed. Flammable and toxic contact adhesives are used in laminating formica and other materials. Painting is discussed in a later section of the chapter. Hardwood dusts can cause nasal cancer, and other respiratory problems. Cutting, sanding, etc. of plywood and particle boards results in the release of formaldehyde, which can cause respiratory irritation and allergies, and causes nasal cancer in animals. Similarly, plexiglass generates methyl methacrylate, also an irritant and sensitizer, when machined. Hand tools, powered hand tools, and fixed woodworking machines are all commonly used. These tools and machines all have safety hazards if not used properly. The following are some basic carpentry safety rules: 1. Everyone should wear safety goggles or safety glasses. A face shield may be worn over these but a face shield by itself does not adequately protect the eyes. Eye glasses are not sufficient protection. 2. NIOSH-approved toxic dust masks should be available and used when necessary. 3. Loose clothing, work gloves, neckties and dangling jewelry should not be worn around powered tools or machines. 4. The work area should always be kept clean, swept, and well-lit. Floors should be free of all debris, slippery materials, or water. 5. Never leave any machine that is running unattended. Turn off the power, and wait until the machine isn't moving before leaving the work area. 6. Safety helmets must be available to all persons working in or visiting a designated "Hard Hat Area". They must be worn at all times while in the area. 7. Hard-soled shoes or boots must be worn at all times within construction, set striking or maintenance areas; while working with heavy objects; or on location. For working on raised structures or conveyances, work shoes or boots with gripping soles should be worn. Rubber-soled boots or shoes should be worn around electrical hazards. Woodworking Machines 1. Machines should be secured. Belts, pulleys, chains, sprockets and gears must be guarded. V-belts and chain drives must be completely enclosed; if belts, shafting, couplings, keys, collars and clutches are located seven or less feet above the ground, these must be guarded from contact. 2. Machine guards should be securely attached to machines, and conform to existing standards, or be specifically designed for the particular machine. 3. Every machine needs an accessible stop switch. 4. Machines should have a master switch. It should be possible to lock the machine in the "off" position. 5. Cutting tools must be maintained and sharp. 6. Scraps and waste should be kept clear of the working surface of the machine. 7. All woodworking machines that generate considerable quantities of wood dust should be equipped with dust collectors that exhaust to the outside. Portable dust collectors are available that can be connected to several machines at once. 8. Hearing protection may be necessary since noise levels from machinery can be very high. A good rule of thumb is that hearing protection is called for when there is difficulty hearing someone one to two feet away. Powered Hand Tools 1. All electric cords must be in good condition, and inspected and maintained. Special precautions must be taken if the work is damp, or contains flammables or combustibles. 2. All guards, shields, and attachments should be in place and functioning. 3. Hand held electrical power tools must have a quick-release (dead-man) control that shuts off power when control switch is released. 4. The frame of electrical tools must be grounded and double-insulated, and thus labeled. 5. Pneumatic tools must be securely fastened to the hose. Additionally, there must be a tool retainer that restrains the attachment. 6. A muzzle should protect autofeed equipment, such as staplers, and nailers, from movement unless there is contact at the work surface. Hand Tools 1. All hand tools must be maintained in good condition, and replaced if damaged. 2. Tools should be stored safely and neatly. There should be procedures for the control of tools. For further information on the hazards and precautions for woodworking machines, powered hand tools and hand tools, see the data sheets prepared by the Canadian Center for Occupational Health and Safety (CCOHS). These are available from the Center for Safety in the Arts. Scaffolding Scaffolds are used in the construction of sets, as well as for camera and lighting supports. 1. OSHA has strict regulations for scaffolding (CFR 1910.29 and 1910.29) 2. Scaffolds should be erected and dismantled by experienced personnel using the proper equipment. 3. Scaffolds should be constructed so they can support up to 4 times the maximum intended load. 4. Scaffolds should follow the Ontario 3 to 1 rule, meaning that the maximum height of a free-standing scaffold should be 3 times the narrowest side of the base. OSHA regulations allow a 4 to 1 ratio. 5. Scaffolds higher than 50 feet require approved plans provided and signed by a professional engineer. 6. Guardrails and toeboards are recommended on all scaffolds, but are required if higher than 8 feet. If the scaffold is less than 45 inches wide, then there must be guardrails on scaffolds over 4 feet. The rail should have a minimum height of 42 inches, and the toeboards should be 4 inches high. 7. Rolling scaffolds (towers) must have proper cross and horizontal bracing, and at least two of four casters or wheels must be swivel type with locking capability. People should not be allowed to ride on manually propelled scaffolds unless there is complete control of the path, the path is smooth and level, there are no overhead obstructions (especially power lines) and the workers are given time to tie down or leave. 8. The location of the scaffold, including foundation area, overhead dangers, and possible public interference must be under control of production company. 9. All towers should be plumbed and leveled. 10. Platforms should have properly decked plywood, as needed. 11. Access on scaffolding should be by properly secured ladders and proper climbing methods. The frames can be climbed, but not the braces. 12. Equipment being ferried up and down the scaffolding must be properly secured. All equipment on top must be secured to the main framework. WELDING, CUTTING AND BRAZING Welding has both health hazards and fire hazards. The metal fumes generated by the welding processes may be toxic (e.g. lead, nickel, cadmium, etc). Zinc and copper-containing metals (e.g. galvanized steel) can cause a flu-like illness called metal fume fever. In addition, arc welding processes can produce highly toxic ozone and nitrogen dioxide gas, as well as large amounts of ultraviolet radiation, which can cause eye damage and skin cancer. Safety Hazards and Fire Prevention OSHA regulations for Welding, Cutting and Brazing are found in CFR 1910.252. Paragraphs (d) and (e) of this section of the OSHA regulations are concerned with fire prevention and protection, and with ventilation. 1. A general statement of fire prevention precautions is found in CFR 1910.252(d)(2)(xv): "Cutting or welding shall be permitted only in areas that are or have been made fire safe. Within the confines of an operating plant or building, cutting and welding should preferably be done in a specific area designated for such work, such as a maintenance shop or a detached outside location. Such areas should be of noncombustible or fire-resistant construction, essentially free of combustible and flammable contents, and suitably segregated from adjacent areas." 2. OSHA requires a fire watch when welding in areas where other than minor fires could occur, if appreciable combustible material is found or exposed through openings within 35 feet of the welding, or if combustible materials adjacent to the opposite side of a metal wall or partition could ignite due to conduction or radiation. Fire watchers shall have extinguishing equipment available, and shall be trained. The fire watch shall be main- tained for at least a half hour after welding has stopped. 3. Administrative measures required by OSHA include establishing specific areas for normal cutting and welding, and establishing procedures for welding and cutting in other areas. An individual should be designated by management to be responsible for authorizing welding and cutting in areas not specifically designated for it. This individual shall inspect the area and designate precautions before authorizing such welding or cutting. 4. Cutters and welders should be suitably trained. It is recommended that at least one welder be certified by the American Welding Society. 5. Areas designated for welding, cutting and brazing should be free of flammable or combustible gases, liquids or vapors. If this is impossible, then these materials must be shielded from heat or sparks. Welding in the vicinity of painting operations can also create fire and health hazards to others in the area, as well as to welders. 6. Welding must be separated from all combustible materials which could be exposed to sparks flying through open doors, windows, cracks in walls or floors. Walls, floors, and all furnishings should be noncombustible or furnished with fire-resistant shields or guards. Floors with combustible shavings, sawdust, should be swept clean for 35 feet. Combustibles within 35 feet must be removed or protected with flameproof coverings or metal shields. 7. Welding, cutting, brazing or hot work may be done only on materials that are thoroughly cleaned of any flammable or combustible material. 8. Gas cylinders must be stored according to the regulations stated in section II-A on Compressed Gases. Acetylene must not be stored at a pressure greater than 15 psi gauge or 30 psi absolute, since above this pressure, acetylene may become unstable. Indoor storage of fuel gas may not exceed 2,000 cubic feet or 300 pounds. 9. Fire extinguishing equipment must be available and maintained. 10. Arc welders should wear clean, fire-resistant gloves and closed, long-sleeved clothing. 11. The welding machine for electric arc welding must be kept dry during use. Welding cable should be spread out during work, and neatly stored afterwards. The ground lead must be attached securely to the work. Any damaged cable must be replaced. There should be regular inspection of cable. Connectors between ground and electrode cables must be specifically designed for that purpose. Spliced cables should never be within ten feet of the operator. Welders should never coil cables around their bodies. Electrode holders not in use should be stored separate from conductive objects. Health Hazards The specific health hazards in welding, cutting and brazing depend on the type of fluxes, metals and coatings, the location of the process, the duration of exposure, and the ventilation. Certain materials require special respiratory protection and ventilation. See Table 5-1 for specific requirements. --------------------------------------------------------------------------- Table 5-1. Respirator and Ventilation Requirements During Welding and Cutting. Material Confined Space Indoors Outdoors Lead A or B A C Zinc A or B A - Cadmium* A or B A or B C Beryllium* A & B A & B A & B Mercury* A or B A or B C Fluorine* A or B - - Stainless steel A A A A = Mechanical local exhaust ventilation by means of hoods or booths having sufficient airflow to maintain a velocity of at least 100 linear feet per minute. B = NIOSH approved supplied-air respirator. C = NIOSH approved respiratory equipment * Only if air contamination under the most adverse conditions are within acceptable concentrations as defined by CFR 1910.1000 --------------------------------------------------------------------------- 1. For metals not listed in the table above, there must be mechanical ventilation when there is less than 10,000 cubic feet of space per welder, if the ceiling is less than 16 feet high, or if the work is being done in an enclosed space. 2. Air velocity must be at least 2000 cubic feet per minute per welder, unless there are hoods or booths for each welder that maintain a velocity of 100 linear feet per minute. Otherwise, approved, supplied-air respirators must be used. 3. When respirators are used, OSHA requires a written respirator program that includes the selection of respirators, training in use and fit testing. (CFR 1910.36 and 1910.37) 4. Goggles, or helmets with eye protection, and hand shields must be used during welding and cutting. 5. Individuals in nearby areas must also be protected or shielded from heat, sparks, and ultraviolet rays. NFPA 51B-1962 Standard for Fire Prevention in Use of Welding and Cutting Operations gives more detailed information. PAINTING Paints, lacquers, varnishes, dye solutions and other coatings are used for scenic painting. These can be solvent-based and water-based. Even water-based paints may still contain 5% or more solvents to help dissolve resin components. Some pigments in paints are toxic if inhaled or ingested, for example lead chromate (chrome yellow). Similarly, many dyes are hazardous by inhalation, and sometimes by skin contact. Spraying of paints and lacquers can result in inhalation of spray mists which can contain organic solvents if the material sprayed is solvent-based. Fine particulates from the sprayed substance can remain in the air for hours before settling. Further, they can penetrate deep into the lungs. Both solvents and propellants (e.g. butane, propane) in spray cans are fire hazards. Powdered Dyes and Pigments Most dyes dissolve in water, although some dissolve in solvents, usually alcohols. The major concern with powdered dyes and pigments is inhalation of the powder. Skin contact can also be a hazard with some dyes, although to a lesser degree. 1. Use liquid dyes and paints whenever possible to reduce risk of inhaling dusts. 2. Water-based dyes are preferred to alcohol-based dyes because of solvent hazards. If alcohol must be used, denatured alcohol or isopropyl alcohol should be used instead of the more hazardous methyl alcohol. 3. Dye and other powders can be mixed into a concentrated solution or paste inside a glove box (e.g. cardboard box with a glass or plexiglass top, and armholes in the ends). This eliminates the need for wearing a toxic dust respirator and messy cleanup procedures. The paste or concentrated dye solution can then be diluted for use as needed. 4. If a glove box is not used for mixing powders, then a NIOSH-approved respirator with a toxic dusts and mists filter should be worn. 5. Do not use bleach to remove dye stains from skin, since bleach is a skin irritant and bleach can decompose dyes to more hazardous chemicals. 6. Spraying bleach onto scenery to decolorize dyes should be done inside a spray booth, or while wearing a full-face, air-purifying respirator with acid gas canister (or half-face respirator with acid gas cartridges and goggles). Eye protection is needed. Solvents and Thinners Solvents are used to dissolve and mix with oils, resins, varnishes and inks; to remove paint, varnish, lacquers; to clean brushes, tools, and even hands. Almost all organic solvents are poisonous if swallowed or inhaled in sufficient quantity, and most can cause dermatitis after sufficient skin contact. High concentrations of most solvents can cause narcosis (dizziness, nausea, fatigue, loss of coordination, coma). Long-term exposure to solvents can cause brain damage, and depending on the solvent, damage to other organs such as the liver, kidneys, heart and reproductive system. In addition to the health hazards, most solvents are flammable or combustible. Flammable liquids have flash points below 100 F (38 C), meaning that enough vapors can collect at the surface of the volatile liquid at normal temperatures to cause a fire if a source of ignition such as a spark or flame is present. Extremely flammable liquids, such as acetone, have flash points below 20 F (-7 C) and are even a more serious fire hazard. Combustible liquids have flash points of 100 F (38 C) or above, meaning that the temperature of the liquid has to be raised above this temperature for sufficient vapors to collect at the liquid's surface to ignite. Note that even combustible materials can ignite at room temperature if they are sprayed. Thus spraying effectively converts a combustible liquid into a flammable one. 1. Obtain Material Safety Data Sheets on solvents (and all other products). 2. Use the safest solvents possible. For example, mineral spirits (paint thinner), especially the odorless type, is less toxic than aromatic hydrocarbons like toluene and xylene. Avoid chlorinated solvents (methylene chloride, perchloroethylene, etc.) whenever possible because most chlorinated hydrocarbons cause cancer in animals, and are probable carcinogens in humans. 3. Avoid skin contact with solvents. In particular, do not use solvents to clean paint off hands. Baby oil or mineral oil is a good substitute. Use gloves to prevent skin contact. 4. Use solvents with adequate ventilation. According to OSHA standards (CFR 1910.1000), solvent vapors concentrations must be kept below the applicable Permissible Exposure Limits (PELs). In order to have an adequate safety factor, I would recommend keeping vapor concentrations below 1/10 of the OSHA PEL (or Threshold Limit Value, if lower). Dilution ventilation (e.g. window exhaust fan) can be used with small amounts of solvents or solvents that are not highly toxic. Otherwise use local exhaust ventilation (e.g. enclosed hood, spray booth, slot hood). 5. OSHA regulations covering the storage and handling of flammable and combustible liquids are found in CFR 1910.106. 6. Keep the minimum amount of solvents practical on hand, and purchase in smallest useful container size. Large amounts of solvents or solvent-containing materials should be stored in an approved flammable storage cabinet. 7. Keep containers closed. Do not allow smoking, open flames or other sources of ignition near solvents. 8. Areas where flammable solvents are transferred should be separated from other areas and provided with proper ventilation. 9. There should be emergency procedures for spill control. 10. There should be a Class B fire extinguisher of at least 12B rating located within 10-25 feet of where flammable solvents are stored, and within 50 feet of areas where flammable solvents are used. Paints and Other Coatings Flammable lacquers, varnishes and shellacs have both serious fire and health hazards. The flammable lacquers are the most hazardous because they usually contain more toxic solvents such as toluene and xylene. Denatured alcohol found in most shellacs and for diluting dyes is less hazardous; methyl alcohol-based shellacs should never be used. Most solvent-based paints, sealers, primers, etc. are combustible, and are not a serious fire hazard at normal temperatures unless sprayed. The most common solvent in combustible paints is mineral spirits, which is a moderate health hazard. If the paints contain substantial amounts of toluene, xylene or aromatic naphtha, then they are more hazardous and may be absorbed though the skin. Aerosol spray paints are always considered extremely flammable because they usually contain propane or other flammable gases under pressure. Water-based paints and other coatings contain small amounts (typically 5-10%) of certain organic solvents that help dissolve the resin and are soluble in water. The least toxic ingredients, by inhalation, of these solvents are propylene glycol, ethylene glycol, and diethylene glycol. The last two are toxic by ingestion. Glycol ethers are more hazardous, with a major concern being reproductive problems in both men and women. Many water-based paints and coatings contain small amounts of ammonia or amines which are skin, eye and respiratory irritants. Water-based paints with mercury preservatives are also hazardous by inhalation and should be avoided. 1. Whenever possible replace solvent-based paints, coatings, etc. with water-based substitutes to eliminate the fire hazard and greatly reduce health hazards. 2. Solvent-based paints and coatings should be mixed in front of a slot hood or inside a spray booth. If powdered pigments or other powders are added that are easily airborne and inhaled, wear a toxic dust respirator. 3. Provide adequate dilution ventilation when brushing or rolling solvent-based paints and other coatings, or spray painting outside a spray booth. Powerful exhaust fans can provide this. These should be left operating until the solvents have evaporated. 4. Large scale coating operations with solvent-containing materials (several gallons at a time) can overload normal dilution ventilation systems. For this type of operation: * Apply the coating at the end of the work day to minimize exposure to personnel. * All personnel not involved in the coating operation should be out of the area. * Dilution ventilation should be provided and left operating all night to remove solvent vapors. * Carefully check to ensure all possible sources of ignition are removed and other fire precautions observed. * Personnel involved in large-scale coating operations should wear positive pressure, air-supplied respirators (e.g. self-contained breathing apparatus). 5. All spraying with flammable or combustible solvents should be done in designated spraying areas or inside explosion-proof spray booths. These spraying areas or booths should comply with the OSHA regulations for spraying finishing using flammable and combustible liquids (CFR 1910.107). 6. If aerosol spray paints are used at locations other than designated spraying areas (e.g. on the finished set), then special precautions should be taken to ensure all sources of sparks, flames, static electricity, hot metal, etc. are removed and provide local exhaust ventilation. 7. When spraying paints or other coatings containing solvents outside a spray booth (including latex paints containing small amounts of solvents), wear a NIOSH-approved, air-purifying respirator with organic vapor cartridges and paint spray (or toxic dusts and mists) filters. If there are no solvents present, only a dusts and mists filter is needed. PROPS AND MODELS Props and miniature models used in motion picture production can be made of a variety of materials, including wood, metal, plastics, etc. The hazards of working in wood and metal were considered earlier. This section will discuss the hazards of plastics and adhesives used for props and models. Plastics Resins Plastics consist of long, chain-like molecules made from smaller molecules (called monomers) linked together. Plastics resins are very hazardous because they involve working with the monomers which are often highly toxic. In addition, toxic solvents, fillers, catalysts, etc. can be used. Polyurethane two-component systems, including paints and expandable foams (AB foams), consist of a polyol component and an isocyanate component. The major hazard from these polyurethane resins is from inhalation of the isocyanates. Isocyanates are strong skin, eye and respiratory irritants and large exposures can cause chemical pneumonia. Chronic or repeated exposure at very low levels (parts per billion in air) can cause severe acute and chronic asthma. TDI (toluene diisocyanate) and MDI (4,4'-methylene diphenyl diisocyanate or 4,4'-diphenylmethane diisocyanate) are the most toxic since they are the most volatile. However, when sprayed, all isocyanates are extremely hazardous. Polyurethane two-component systems can also contain other toxic chemicals, including solvents and irritating amine catalysts. Polyester resin systems (fiberglass resins) consist of a resin, which contains a polyester polymer dissolved in styrene, and a hardener, methyl ethyl ketone peroxide (MEK peroxide), dissolved in dimethyl phthalate. Styrene is a strong respiratory irritant and narcotic, and requires very good local exhaust ventilation. MEK peroxide is a strong skin irritant and can cause blindness from even a few drops splashed in the eye. It is also heat and shock sensitive if the solvent evaporates. The hardener should never be mixed with acetone, since it will react with acetone to form the explosive acetone peroxide. Epoxy systems include resins, glues and paints. The epoxy resin itself usually contains diglycidyl ethers which are skin, eye and respiratory irritants and suspect carcinogens. The epoxy hardeners can include amines, anhydrides and several other chemicals. These chemicals cause skin irritation and allergies. Other plastic resins are used for props, for example in making break- away glass. Fire hazards from the solvents can be a particular hazards (see Solvents and Thinners section). 1. Polyurethane foam resins should not be sprayed due to their extreme toxicity, except in a spray booth. If absolutely essential, self-contained breathing apparatus (SCBA) should be worn if a spray booth is not available, or the piece is too large. SCBA should only be worn by personnel trained in its use. 2. Casting or hand layup with polyurethane foam, polyester or epoxy resins should take place inside a walk-in spray booth. The operator should wear a full-face, air-purifying respirator with organic vapor canister. 3. Large scale application of plastics resins outside a spray booth requires excellent dilution ventilation and air-supplied respirators. 4. Wear gloves, goggles, and protective clothing when working with plastics resins. Goggles or full-face respirator are needed especially when mixing polyester resin because of the risk of blindness if the MEK peroxide hardener is splashed in the eyes. 5. See Solvents and Thinners section for other precautions when working with plastics resins. Fabricating Plastics The hazards involved in working with finished plastics come mostly from the methods used to work the plastic. Burning of plastic can result in the release of carbon monoxide and other toxic gases from the decomposition of the plastic. This can also occur during sawing or machining. Heating of plastics can result in the release of unreacted monomer, plasticizers or other chemicals which are trapped in the plastic. The glues and cements used to bond plastics often contain toxic solvents and plastic monomers. See the Adhesives section for detailed information. 1. Sanding, cutting and other heating of finished polyurethane foam causes decomposition of the foam to yield toxic gases such as hydrogen cyanide. Working in a spray booth or wearing SCBA is recommended. 2. Celastic is a nitrocellulose plastic that can often be used as a substitute for polyurethane AB foams. Hand layup with celastic and acetone can be done inside a spray booth or with dilution ventilation. Although acetone is only slightly toxic, it is extremely flammable, and all OSHA requirements for handling flammable liquids must be strictly observed, especially with respect to electrical wiring and equipment. If dilution ventilation is not adequate protection due to having to work very close to the acetone, then wearing an air-purifying respirator with organic vapor cartridges is recommended. 3. Styrofoam carving, cutting and other finishing processes do not present major hazards. Dilution ventilation suitable for solvent use will exhaust any toxic gases produced by decomposition of the styrofoam. When using hot wire cutting, use lowest temperature possible to minimize decomposition. If large amounts of dust are generated, then wearing a NIOSH-approved, toxic dust respirator is recommended. 4. When cutting, sanding or otherwise creating dust when fabricating plastics, frequent vacuuming should be done to remove accumulated dust. 5. If respiratory protection is used, make sure you have the correct cartridges and filters. For polyvinyl chloride (PVC) use acid gas cartridge plus dusts and mists filter; for plexiglas use organic vapor cartridge, plus dusts and mists filter. Adhesives Many adhesives contain solvents that are toxic by inhalation and skin contact. For example, rubber cements and contact adhesives usually contain n-hexane, which can cause peripheral neuropathy (damage to nerves of hands, feet, arms, legs). Glues used in furniture repair, model making or leatherwork often contain hazardous solvents like toluene and naphthas. These are hazardous by skin contact and inhalation, and most are flammable. See Solvents and Thinners section for more information. Some adhesives work by polymerization of hazardous monomers. Epoxy glues were discussed under plastics resins. Acrylic plastic glues can contain methyl methacrylate, and instant bonding glues contain cyanoacrylates. These ingredients are skin sensitizers and irritants, and the vapors may cause headaches, loss of appetite and low blood pressure. Cyanoacrylate glues can bond skin. Woodworking glues range from polyvinyl acetate (PVA) emulsion glues that are water-based, to hazardous resorcinol formaldehyde resins that release formaldehyde gas. Formaldehyde is a skin, eye and respiratory irritant and sensitizer, and is a suspected human carcinogen. Other wood glues may contain toxic phenol preservatives. Aerosol adhesives are sprayed, resulting in the inhalation of rubber or plastic particles, along with the inhalation of various solvent and propellent ingredients. N-hexane, which can cause nerve damage, is a common solvent used in these spray formulations. Both solvents and aerosol propellants are fire hazards. 1. Substitute the safest glue possible. 2. Use solvent-based glues in a well-ventilated space (e.g. window exhaust fan). If large amounts are being used, local exhaust ventilation such as a slot exhaust hood is necessary. Placing the work table up against a window with an exhaust fan at work level is also effective. Eliminate all sources of ignition such as flames, sparks or lit cigarettes. 3. Spray adhesives could be used outdoors for occasional projects, or in a sparkproof spray booth that exhausts to the outside. 4. See also precautions under Solvents and Thinners. REFERENCES American Conference of Governmental Industrial Hygienists. (1990). Threshold Limit Values for Chemical Substances and Physical Agents in the Work Environment. ACGIH, Cincinnati. American National Standards Institute. (1983). ANSI Z49.1-1983. Safety in Welding and Cutting. ANSI, New York. Canadian Centre for Occupational Health and Safety. (1988). Infograms on Abrasive Wheels, Chain Saws, Hand tools, Materials Handling, Power Hand tools, Welding, Woodworking. CCOHS, Hamilton. Clark, N., Cutter, T., and McGrane, J. (1984). Ventilation. Lyons and Burford Books, New York. Industrial Hygiene Subcommittee, Alliance of American Insurers. (1986). Handbook of Organic Industrial Solvents, 6th Edition. Alliance of American Insurers, Chicago. McCann, M. (1979). Artist Beware: The Hazards and Precautions in Working With Art and Craft Materials. Watson-Guptill Publications, New York. National Fire Protection Association. (1962). NFPA 51B-1962 Standard for Fire Prevention in Use of Welding and Cutting Operations. NFPA, Quincy, MA. Occupational Safety and Health Administration. (1989). Occupational Safety and Health Standards For General Industry, 29 CFR Part 1910. OSHA, U.S. Department of Labor, Washington, DC. Occupational Safety and Health Administration. (1989). Occupational Safety and Health Standards For Construction, 29 CFR Part 1926. OSHA, U.S. Department of Labor, Washington, DC. Patty, F. (Editor). (1982). Industrial Hygiene and Toxicology. Volume Two (3 Parts), Third Edition. Interscience Publishers, New York. Rossol, M. (1986). Stage Fright: Health and Safety in the Theater. Allsworth Press, New York.