## Facts

- Durez Division of Occidental Chemical Corporation manufactured “Durez 153,” a phenol-formaldehyde compound sold to downstream manufacturers for molding into heat-resistant products.
- During downstream molding, Durez 153 released small quantities of phenol vapor into workplace air.
- OSHA’s Hazard Communication Standard (HCS) required chemical manufacturers to investigate hazards, label hazardous chemicals, and provide a Material Safety Data Sheet (MSDS) listing health hazards, signs and symptoms of exposure, and conditions aggravated by exposure.
- Phenol was a regulated air contaminant under OSHA regulations and therefore subject to HCS hazard-communication requirements.
- Durez’s MSDS disclosed relatively minor phenol effects (e.g., irritation) but omitted more serious chronic/systemic effects associated with phenol overexposure (e.g., potential liver, kidney, and heart damage).
- OSHA cited Durez for failing to disclose all potential phenol hazards on the MSDS; the Occupational Safety and Health Review Commission upheld the citation, reading the HCS to require disclosure of all potential hazards regardless of expected downstream exposure levels.
- Durez petitioned for judicial review, arguing the HCS required disclosure only of hazards tied to foreseeable downstream exposure levels posing a realistic risk.

## Issues

1. Whether the HCS requires an MSDS to disclose all potential health hazards associated with a hazardous chemical, including serious chronic effects, even if the manufacturer believes downstream exposure levels will not realistically cause those harms.
2. Whether circuit precedent foreclosed Durez’s challenge to the Commission’s interpretation, requiring deference to the Secretary of Labor’s construction of the HCS in this enforcement context.

## Decision

- The court denied the petition for review and left the citation affirmed.
- The court held that prior circuit precedent foreclosed Durez’s attempt to challenge the Commission’s interpretation of the HCS.
- As a result, the court accepted the agency’s interpretation that the MSDS must include all potential health hazards of phenol, not a subset filtered by the manufacturer’s expected downstream exposure assessment.

## Legal Principles

- Under the HCS, an MSDS for a hazardous chemical must disclose the chemical’s health hazards, including acute and chronic effects supported by scientifically valid evidence.
- For chemicals covered by the HCS, disclosure duties are not limited to hazards the manufacturer believes are likely to occur under particular downstream conditions of use.
- In enforcement review proceedings involving OSHA standards, the court will defer to the Secretary’s reasonable interpretation of the agency’s own standard where controlling circuit precedent limits relitigation of that interpretive question.

## Conclusion

The D.C. Circuit upheld OSHA’s citation requiring Durez to expand its MSDS to include serious chronic phenol hazards, concluding that controlling circuit precedent required deference to the Secretary’s interpretation that the HCS mandates disclosure of all potential chemical health risks.


Durez Div. of Occidental Chem. Corp. v. Occupational Safety & Health Admin., 906 F.2d 1 (D.C. Cir. 1990)