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May 1994

Documentation for Immediately Dangerous To Life or Health Concentrations (IDLHs)


CAS number: 7782–41–4

NIOSH REL: 0.1 ppm (0.2 mg/m3) TWA

Current OSHA PEL: 0.1 ppm (0.2 mg/m3) TWA

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 1 ppm (1.6 mg/m3) TWA, 2 ppm (3.1 mg/m3) STEL

Description of Substance: Pale-yellow to greenish gas with a pungent, irritating odor.

LEL: . . Nonflammable Gas

Original (SCP) IDLH: 25 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by AIHA [1965] that "2 men were able to tolerate 25 ppm very briefly but both developed sore throats and chest pains lasting 6 hours; 50 ppm could not be tolerated [Rickey 1959]."

Existing short-term exposure guidelines: National Research Council [NRC 1984] Emergency Exposure Guidance Levels (EEGLs):

10-minute EEGL: 15 ppm

30-minute EEGL: 10 ppm

60-minute EEGL: 7.5 ppm


Lethal concentration data:







Adjusted 0.5-hr







G. pig

Keplinger and Suissa 1968

Keplinger and Suissa 1968

Keplinger and Suissa 1968

Keplinger and Suissa 1968









1 hr

1 hr

30 min

1 hr

231 ppm (1.25)

188 ppm (1.25)

270 ppm (1.0)

213 ppm (1.25)

23 ppm

19 ppm

27 ppm

21 ppm

Human data: It has been reported that 2 men were able to tolerate 25 ppm very briefly but both developed sore throats and chest pains that lasted 6 hours; 50 ppm could not be tolerated [Rickey 1959]. Volunteers tolerated 10 ppm for 15 minutes with a minimum of irritation [Ricca 1970]. Intermittent exposures to 10 ppm were repeated every 3 to 5 minutes for 15 minutes over 2 to 3 hours with only slight irritation of the eyes and skin noted [Ricca 1970]. Much irritation of the eyes have been noted at 100 ppm, but with no aftereffects after only 30 seconds [Grant 1974]. It has been observed that exposures up to 30 ppm for 5 to 30 minutes had no ill effects [Lyon 1962].


Revised IDLH: 25 ppm [Unchanged]

Basis for revised IDLH: Based on acute inhalation toxicity data in humans [Grant 1974; Lyon 1962; Ricca 1970; Rickey 1959], the original IDLH for fluorine (25 ppm) is not being revised at this time.


1. AIHA [1965]. Fluorine (revised 1965). In: Hygienic guide series. Am Ind Hyg Assoc J 26:624-627.

2. Grant WM [1974]. Toxicology of the eye. 2nd ed. Springfield, IL: C.C. Thomas, p. 499.

3. Keplinger ML, Suissa LW [1968]. Toxicity of fluorine short-term inhalation. Am Ind Hyg Assoc J 29:10-18.

4. Lyon JS [1962]. Observations on personnel working with fluorine at a gaseous diffusion plant. J Occup Med 4:199-201.

5. NRC [1984]. Emergency and continuous exposure limits for selected airborne contaminants. Vol. 1. Washington, DC: National Academy Press, Committee on Toxicology, Board on Toxicology and Environmental Health Hazards, Commission on Life Sciences, National Research Council, pp. 77-88.

6. Ricca PM [1970]. A survey of the acute toxicity of elemental fluorine. Am Ind Hyg Assoc J 3:22-29.

7. Rickey RP [1959]. Decontamination of large liquid fluorine spills. Arlington, VA: Edwards Air Force Base, ASTIA Document Service Center, Air Force Flight Test Center Technical Report 59-31.

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