Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 110–54–3
NIOSH REL: 50 ppm (180 mg/m3) TWA
Current OSHA PEL: 500 ppm (1,800 mg/m3) TWA
1989 OSHA PEL: 50 ppm (180 mg/m3) TWA
1993-1994 ACGIH TLV: 50 ppm (176 mg/m3) TWA
Description of Substance: Colorless liquid with a gasoline-like odor.
LEL:. . 1.1% (10% LEL, 1,100 ppm)
Original (SCP) IDLH: 5,000 ppm
Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by Patty  that a 10-minute exposure to 5,000 ppm caused dizziness and a sensation of giddiness [Patty and Yant 1929]. Because these symptoms could impede escape, 5,000 ppm is judged to be the IDLH.
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA
Lethal dose data:
|Rat||Kimura et al. 1971||oral||28,710||56,137||5,614 ppm||-----|
Human data: It has been reported that a 10-minute exposure to 5,000 ppm caused dizziness and a sensation of giddiness [Patty and Yant 1929].
|Revised IDLH: 1,100 ppm [LEL]
Basis for revised IDLH: Based on health considerations and acute toxicity data in humans [Patty and Yant 1929], a value of about 2,500 ppm would have been appropriate. However, the revised IDLH for n-hexane is 1,100 ppm based strictly on safety considerations (i.e., being 10% of the lower exposure limit of 1.1%).
1. Kimura ET, Ebert DM, Dodge PW . Acute toxicity and limits of solvent residue for sixteen organic solvents. Toxicol Appl Pharmacol 19:699-704.
2. Patty FA, ed. . Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1198.
3. Patty FA, Yant WP . Odor intensity and symptoms produced by commercial propane, butane, pentane, hexane, and heptane vapor. Pittsburgh, PA: Department of Commerce, U.S. Bureau of Mines, Report of Investigations, No. 2979, pp. 1-10.