Associate Safety Professional Practice Exam

Why is 1,1,1-Trichloroethane sometimes substituted for Trichloroethylene?

1. It is less toxic

2. Its TLV is higher

3. It is less expensive

4. It evaporates faster

The correct answer is: Its TLV is higher

The correct choice for the reason why 1,1,1-Trichloroethane is sometimes substituted for Trichloroethylene is that its Threshold Limit Value (TLV) is higher. A higher TLV indicates that the substance can be safely exposed to workers at a higher concentration compared to substances with lower TLVs. This can make certain industrial applications more feasible, as it allows for greater flexibility in the amount used without exceeding safety standards for exposure. In practice, operating under conditions where a substance has a higher TLV can also mean reduced regulatory burdens and less stringent monitoring practices, because the permissible exposure levels are higher. This factor can be particularly attuned to the overall safety program of an organization, as it can help minimize the risks associated with exposure. The other options present various attributes of the substances involved but do not directly correlate with the common reasoning for substituting one chemical for another in workplace settings. For instance, considerations regarding toxicity, costs, and evaporation rates may influence selections but do not necessarily highlight the occupational exposure and regulatory impacts provided by the TLV measure.