Contact: Lisa Dry (202) 249-6523  

ACGIH Decision is Not Supported by Any New Scientific Information

WASHINGTON (March 28, 2016) - On February 1 the American Conference of Governmental Industrial Hygienists (ACGIH) lowered their recommended occupational exposure levels, known as threshold limit values (TLVs), for Toluene-2,4-diisocyanate and Toluene-2,6-diisocyanate (TDI). The lowered TLVs were adopted despite extensive scientific information that the Panel had provided to ACGIH over a ten year period clearly indicating that the previous TLV levels were satisfactorily protective of workers. TDI is a chemical used in the production of polyurethanes. The American Chemistry Council's (ACC) Diisocyanates Panel issued the following statement about the ACGIH action:

"ACC's Diisocyanates Panel is committed to the prevention of occupational asthma associated with the inhalation of excessive amounts of TDI. The best available science shows that the current OSHA Personal Exposure Level (PEL) ceiling value for TDI is appropriate to protect workers provided it is adhered to strictly. Accordingly, achieving full compliance with, and enforcement of, the current PEL is the best way to protect TDI-exposed workers from occupational asthma.

"We are not aware of any new scientific information introduced regarding TDI since ACGIH evaluated TDI levels in 2004. There is a lack of transparency in the ACGIH TLV development process, with no opportunity for the affected industry to participate, as evidenced by the fact that for ten years ACGIH has rebuffed repeated industry requests to meet and has also failed to respond to comments submitted by the Panel.

"ACGIH, as a private organization, has stated that it does not consider economic and technical feasibility when deriving chemical exposure levels as required by standard-setting agencies of the federal government, such as OSHA. ACGIH's decision to lower the TLVs has the potential to cause real economic harm to businesses that will be required to install expensive engineering controls without any perceived benefit to worker safety.

"The Panel, therefore, does not believe there is a need to reduce the TLVs for TDI. We continue to support reasonable and appropriate monitoring or other exposure assessments and medical surveillance of employees who are potentially exposed to significant levels of TDI.

"The Panel makes available extensive product stewardship resources ( and ) on workplace engineering controls, personal protective equipment and medical surveillance to help protect worker health. With the proper workplace practices, TDI can be used safely in occupational settings."

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