Safety Tidbit 4.23 – ACGIH TLVs – What they are not

Safety Tidbit 4.23 – ACGIH TLVs – What they are not

Reference: ACGIH TLV/BEI Guidelines - Overview

Industrial hygienists routinely reference the Threshold Limit Values when evaluating air contaminants in the workplace. But what are these TLVs?  ACGIH states:

 “TLVs^® and BEIs^® are health-based values established by committees that review existing published and peer-reviewed literature in various scientific disciplines (e.g., industrial hygiene, toxicology, occupational medicine, and epidemiology). Since TLVs^® and BEIs^® are based solely on health factors, there is no consideration given to economic or technical feasibility.”

Furthermore, the TLVs represent the opinion of the scientific community which has reviewed the data described in the ACGIH’s documentation publications, that exposure at or below the level of the TLV^® or BEI^® does not create an unreasonable risk of disease or injury.  Ultimately, industrial hygienists are strongly warned to only use the TLVs^® and BEIs^® as a part of their consideration when evaluating specific workplace situations and conditions.

So, what are the TLVs not?

a.     The TLVs are not a fine line between safe and dangerous conditions and therefore are not a common denominator for safety.

b.     Not proof of injury when exposure is at or above the TLV. Many workers will have no ill effects if exposed to the level of the TLV. The TLV is meant to protect nearly all workers.

c.     Not to be used as air pollution values where the source of the contaminant may be from a continuous, uninterrupted source. TLVs are designed for workplace situations.

d.     No legal standards as neither economic nor technologic feasibility are taken into consideration. They are purely determined based on health effects and the available data.

Ultimately, the TLVs “refer to airborne concentrations of chemical substances and represent conditions under which it is believed that nearly all workers may be repeatedly exposed, day after day, over a working lifetime, without adverse health effects.”

Hope this was helpful and thank you for reading my Safety Tidbits! Comments and questions are always welcome. ~ Bryan

P.S. If you have a new safety or health question, please let me know.