Hazards substitution

Arsine (ASH3) and phosphine (PH3) are extremely toxic, so less hazardous substitutes such as tertiary butyl arsine, C4H1 j As, and tertiary butyl phosphine, C4H11P, are being considered. 

The chemical process industries employ many substances that contribute to air and water pollution, hazardous waste generation, soil contamination, fire and explosion risks, and the exposure of humans, animals and plants to hazardous and/or toxic substances. This article discusses which substances are hazardous and identifies the opportunities for replacing these substances with less-hazardous substitutes. 

If REACH allows the continued production of chemicals of very high concern under a provision for adequate control, even when intrinsically less hazardous substitutes are available, it will not provide the high level of protection for human health and the environment required underthe EU Treaty. 

DMAP [(4-(A/,A-dimethylamino)pyridine, DMAP-H" 9.70] is a versatile hypernucleophilic catalyst for the preparation of ethers and esters. Toxicological data of DMAP show that the compound should be handled with care. DABCO (1,4-diazabicy-clo[2.2.2]octane) appears to be a less hazardous substitute for the widely used DMAP. 

The substitution principle , adopted in Sweden s 1990 Act on Chemical Products, which reads, in part, Anyone handling or importing a chemical product must take such steps and otherwise observe such precautions as are needed to prevent or minimize harm to man or the environment. This includes avoiding chemical products for which less hazardous substitutes are available . 

Indeed the principle has been enshrined in many international forums, particularly those that have set the generational goal to achieve the elimination of hazardous substances (Thorpe, 2003). The Nordic countries, in particular, have based many of their chemical policies round the principle of substitution. Most notable is the Swedish Chemicals Products Act of 1985, which puts the onus on anyone handling or importing a chemical to avoid chemical products for which less hazardous substitutes are available (Geiser and Tickner, 2003). 

The QSAR-partial order ranking system further appears as an appropriate tool to give specific molecules an identity in relation to others and thus constitute as a support tool in the development of less hazardous substitutes to acknowledged harmful substances. In this connection partial order ranking potentially also constitute a rather strong tool to solve inverse QSAR problems, e.g., to develop suitable synthetic pathways for new substances. 

Notwithstanding the fact that whether or not a work area is exenqjted from exposure measurements, other obligations of the employer according to the Ordinance of Hazardous Susbstances remain in force such as its obligation to use less hazardous substitutes if... 

Hazardous Material Properties Prevent/ Mitigate Identify less hazardous substitutes Less hazardous substitutes may have cost implications that do not justify the risk reduction benefits... 

Use of non-hazardous or less hazardous substitutes when appropriate ... 

Solvents are widely used in organic reactions. These liquids are often flammable and have varying degrees of toxicity. As illustrated in Incident 1.2.2.1 there is always the possibility of fires when handling flammable solvents, especially if there are unrecognized ignition sources in the vicinity. While we really don t know speciflcally what the researcher was doing or why the particular 10% ethyl acetate/90% petroleum ether solvent was chosen for her work, one can speculate that perhaps a less hazardous substitute or a smaller scaled experiment could have been considered for her experiments. 

Less hazardous substitute. Ask if it is possible to substitute a less hazardous chemical before you order. 

The primary philosophy is to follow the principles of inherent safety. This implies a systematic effort to apply the principles of hazard elimination, minimization/ intensification, hazard substitution, moderation/attenuation, and simplification. However, additional controls will still be required to control a hazardous situation, prevent escalation, and mitigate the risk to people, to the environment, asset, and reputation. Preferably, these safeguards will be passive- or active-engineered controls rather than administrative controls (i.e., dependent on direct human intervention). 

Reduce Your Hazards Find ways to make your operation safer. You could reduce your inventory ofhazardous substances, find less hazardous substitutes, or change your processes. 

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-... 

The most desirable solution to preventing chemical releases is to reduce or eliminate the hazard where possible, not to control it. This can be achieved by modifying processes where possible to minimize the amount of hazardous material used, lower the temperatures and pressures required, replace a hazardous substance with a less hazardous substitute, or minimize the complexity of a chemical process. 

According to Public Services Health and Safety Association (2011), hazard/risk prevention or control measures can be implemented at the source level (e.g. elimination of the hazard, substitution, and redesign), along the path (e.g. during processing and transporting of the drilling waste), and at the worker. 

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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