Page 237 - IGC BOOK

Elimination or Substitution of Hazardous Substances

Elimination

The first priority for control of any significant risk to health is to try to eliminate completely
the agent responsible in the first place. For each of the agents we have examined, the option
usually exists to eliminate the hazard at source by replacement with materials which do the
same job but present no risk to health. Improvements in technology often present the
opportunity to replace older hazardous processes or activities with those involving no risk to
health; for example, the use of new water-based materials such as paints or adhesives can
eliminate completely the risk to health of exposure to solvents.

Elimination requires a careful examination of the work activity and process, and demands a
good understanding of the properties and behaviour of alternative substances and materials.
It may also be the costliest method of risk control, since it may involve a radical change in the
way in which the work is carried out. However, the elimination of hazards is the key objective
of the health and safety programme and the opportunities available should be re- examined
every time an assessment is reviewed.

Substitution

Although elimination of risk is the ideal it is often not practicable. The next option then
becomes reducing the risk by substituting the hazard with a different one with less potential
for harm; for example:

• Using the same material but in a different physical form, such as using granulated pottery
glazes rather than powders to reduce the risk of dust inhalation.
• Using a similar, but different substance altogether, such as one with a lower volatility
and/or higher WEL.

Since the risk is not completely eliminated but only reduced, it is essential to ensure that the
potentially harmful properties of any proposed replacement are fully taken into account to
ensure substitution does not introduce different but equally unacceptable risks.

Process Changes

In some circumstances an analysis of the process itself may identify specific activities which
produce harmful substances or agents. In these cases, changing the work method may
minimise or suppress the generation of the agents of concern; for example:

• Brush painting rather than spraying will considerably reduce the level of airborne
contaminant.

ENSIGN| Unit IG2 – Element 7 – Chemical and Biological 32
Agents