Substitution of less hazardous materials

Substitution means the replacement of a hazardous material or process with an alternative which reduces or eliminates the hazard. Process designers, line managers, and plant technical staff should continually ask if less hazardous alternatives can be effectively substituted for all hazardous materials used in a manufacturing process. Examples of substitution in two categories are discussed—reaction chemistry and solvent usage. There are many other areas where opportunities for substitution of less hazardous materials can be found, for example, materials of construction, heat transfer media, insulation, and shipping containers. 

A. Elimination or reduction of further exposure is a key treatment intervention in occupational toxicology. This includes prevention of exposure of coworkers. The Occupational Safety and Health Administration (OSHA) may be of assistance and should be notified immediately about an ongoing, potentially life-threatening workplace exposure situation. Contact information for region OSHA offices is listed in Table IV-3. Workplace modification and control, especially the substitution of less hazardous materials, should always be the first line of defense. Worker-required personal protective equipment is, in general, less preferred. 

B. Substitution of less hazardous materials, processes, operations, or equipment... 

B. Substitution of Less Hazardous Materials, Processes, Operations, or Equipment Processes... 

While minimization possibilities are being investigated, substitutions should also be considered as an alternative or companion concept that is, safer materials should be used in place of hazardous ones. This can be accomplished by using alternative chemistry that allows the use of less hazardous materials or less severe processing conditions. When possible, toxic or flammable solvents should be replaced with less hazardous solvents (for example, water-based paints and adhesives and aqueous or dry flowable formulations for agricultural chemicals). 

It may be possible to substitute a less hazardous material for a hazardous product. For example, bleaching powder can be used in swimming pools instead of chlorine.4 Benzoyl peroxide, an initiator used in polymerization reactions, is available as a paste in water, which makes it much less shock-sensitive than the dry form. Other substitutions that have been used to make transportation, storage, and processing safer include ... 

Substitution of the processing route with one using less hazardous material. Or, substitution of toxic process materials with non-toxic, or less toxic materials. 

The combination of toxic hazard and high price (itself in part due to the extra measures needed in production processes to ensure the workers safety) has been an effective brake on commercial development of beryllium chemistry. Where possible substitute, albeit less effective, materials are often used titanium as an alternate lightweight metal or carbon fiber composites, phosphor-bronzes in place of beryllium alloys, aluminum nitride in place of BeO (1). 

The Substitution Principle is closely tied to the general goal of elimination, which is manifested in Article 5. A direct consequence of the employment of the Substitution Principle is the application of best Available Technologies (BAT) and Best Environmental Practice (BEP) when dealing with unintentional sources as classified in Annex C. BAT as such also requires the use of less hazardous substances. (Annex C, part V, (A (b)) again refers to the Substitution Principle demanding in para (d) the replacement of feed materials which are POPs or where there is a direct link between the materials and releases of POPs from the source and consequently health effects and harm for humans and the environment. 

Substitution Sometimes substitution of a less hazardous material is feasible. For example, many chlorinating systems for water purification have recently converted from pressurized cylinders of liquid chlorine to a pelletized, hypochlorite salt. 

Basic or detailed changes in the way the process is permitted to operate can eliminate or reduce exposure. For example, rather than handling a material as a dry powder, it might be handled as a slurry or in solution. A special case of process change involves the substitution of a less hazardous material in the process for a more hazardous one. If such a substitution is not possible, then it may be necessary to completely isolate the process from the worker, as has been done in the manufacture of HCN (prussic acid). 

The hazard characteristics of materials will affect exposure and risk. More hazardous materials inherently have a greater probability of adverse health outcomes upon exposure. Sometimes employees will be more careful when using materials that they know have a high hazard potential. But this can only be true when they are knowledgeable about the material s hazard level. If a material is very hazardous, often less-hazardous materials available can be substituted. The same is true for hazardous work processes. Proper substitution can decrease the risk of injury or illness, but care must be taken to ensure that the material or process being substituted is really safer and that it mixes well with the entire product formulation or production/assembly process. 

For situations where less hazardous materials cannot be substituted in the process, engineering methods are the most important method of control and should be applied in all cases. Engineering methods are defined as any aspects... 

Substitution — Means using less hazardous materials in your operation. For example, try using abrasives containing a lower percentage of crystalline silica during blasting operations. 

Substitution Replacing a hazardous material with a nonhazardous materials removes the danger of a hazardous material exposure. Replacing a hazardous material with one that is less hazardous may be a desirable substitution. If an alternate material does not perform as well as the original material, substitution may not produce a desirable solution. 

A good way to minimize the dangers of hazardous waste is to prevent their generation. This may be possible by substituting less hazardous material in a process or using materials that do not produce hazardous waste. One may also change a process. This may prevent the generation of hazardous waste or reduce the amount of hazardous material used or created. 

Refer to Chapter 11 for a detailed review of this program. You should minimize hazards by substituting less hazardous materials or equipment whenever possible and engineering controls that distance the worker from the hazard. For the remaining hazards, design safe work practices, train your employees adequately in these practices, and enforce the practice consistently. In some cases, you may also need to establish other administrative controls, such as employee rotation or more frequent work breaks where needed. 

In 2012, OSHA changed the HCS drastically, using the concept that the employees have a right to understand about the hazards of chemicals they are exposed to. They also need to know what they can do to protect themselves. Additionally, when employers have information about the chemicals being used, they can take steps to reduce exposures, substitute less hazardous materials, and establish safe work practices to prevent illnesses and injuries caused by these substances. 

Substitution is sometimes possible by ublising a less hazardous material instead of a more hazardous one. An example is in the replacement of benzene (WEL1 ppm) that is a proven human carcinogen by toluene (WEE 50 ppm) which is in many cases as good a solvent. This option requires a good xmderstanding of the hazardous properties of both materials to ensure that new or addibonal hazards are not introduced into the workplace by the replacement material. 

A emunon mistake wben substimting materials is to replace a chemical of known toxicity with one t ch has not been adequately or completely evaluated for toxicity, under the assumption diat lack of information implies that a chemical is s. The identification of less hazardous substitutes will depend on having adequate and current data and to-... 

Controlling exposure is the best method of protecting range worters and shooters. Generally this means elimination of the hazard, substitution of a less hazardous material, engineering controls, administrative controls (to reduce time of exposure) and personal protective equipment. 

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