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Petroleum distillates (naphtha)

May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)

CAS number: 8002–05–9

NIOSH REL: 350 mg/m3 TWA, 1,800 mg/m3 15-minute CEILING

Current OSHA PEL: 500 ppm (2,000 mg/m3) TWA

1989 OSHA PEL: 400 ppm (1,600 mg/m3) TWA

1993-1994 ACGIH TLV: 400 ppm (1,590 mg/m3) TWA

Description of substance: Colorless liquid with a gasoline- or kerosene-like odor.

LEL: . . 1.1% (10% LEL, 1,100 ppm)

Original (SCP) IDLH: 10,000 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by AIHA [1963] that the atmospheric concentrations immediately hazardous to life are from 10,000 to 20,000 ppm [Henderson and Haggard 1943]. In addition, the short exposure tolerance to petroleum naphtha is based on a statement by AIHA [1963] that 4,000 to 7,000 ppm may be tolerated for 1 hour [Henderson and Haggard 1943], but not without development of definite symptoms of narcosis [Drinker et al. 1943].

Short-term exposure guidelines: None developed


Animal data: None relevant for use in determining the revised IDLH.

Human data: It has been reported that concentrations of 10,000 to 20,000 ppm are immediately dangerous to health [Henderson and Haggard 1943]. It has also been stated that concentrations of 4,000 to 7,000 ppm could be tolerated for 1 hour, but not without definite symptoms of narcosis [Drinker et al. 1943].


1. AIHA [1963]. Petroleum naphtha. In: Hygienic guide series. Am Ind Hyg Assoc J 24:427-428.

2. Drinker P, Yaglou CP, Warren MF [1943]. The threshold toxicity of gasoline vapor. J Ind Hyg Toxicol 25:225-232.

3. Henderson Y, Haggard HW [1943]. Noxious gases. 2nd ed. New York, NY: Reinhold Publishing Corporation, p. 192.