Hydrogen fluoride (as F)
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 7664–39–3
NIOSH REL: 3 ppm (2.5 mg/m3) TWA, 6 ppm (5 mg/m3) 15-minute CEILING
Current OSHA PEL: 3 ppm TWA
1989 OSHA PEL: 3 ppm TWA, 6 ppm STEL
1993-1994 ACGIH TLV: 3 ppm (2.6 mg/m3) CEILING
Description of Substance: Colorless gas or fuming liquid (below 67°F) with a strong, irritating odor.
LEL:. . Nonflammable Gas/Noncombustible Liquid
Original (SCP) IDLH: 30 ppm
Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by Patty [1963] that 24 mg/m3 (30 ppm) was tolerated by animals for a total of 41 hours without a fatality [Machle et al. 1934]. A concentration of 50 ppm is obviously too high to be selected as the IDLH, because Deichmann and Gerarde [1969] stated that 50 ppm may be fatal when inhaled for 30 to 60 minutes.
Existing short-term exposure guidelines: National Research Council (NRC) Emergency Exposure Limits (EELs) recommended to military and space agencies [Smyth 1966]
10-minute EEL: 20 ppm
30-minute EEL: 10 ppm
60-minute EEL: 8 ppm
ACUTE TOXICITY DATA:
Lethal concentration data:
| Species | Reference | LC50 (ppm) | LCLo (ppm) | Time | Adjusted 0.5-hr LC (CF*) | Derived value |
| Rat | Darmer et al. 1972 | 1,276 | ----- | 1 hr | 1,799 ppm (1.41) | 180 ppm |
| Monkey | MacEwen & Vernot 1970 | 1,774 | ----- | 1 hr | 2,501 ppm (1.41) | 250 ppm |
| Rabbit | Treon et al. 1950 | ----- | 313 | 7 hr | 1,171 ppm (3.74) | 117 ppm |
| G. pig | Wohlslagel et al. 1976 | 4,327 | ----- | 15 min | 3,072 ppm (0.71) | 307 ppm |
*Note: Conversion factor (CF) was determined with "n" = 2.0 [ten Berge et al. 1986].
Other animal data: Guinea pigs and rabbits survived exposures to 30 ppm for 41 hours, but exposures to 300 ppm for 2 hours or more were fatal [Machle et al. 1934].
Human data:
It has been stated that 50 ppm may be fatal when inhaled for 30 to 60 minutes [Deichmann and Gerarde 1969]. Volunteers tolerated concentrations as high as 4.7 ppm for 6 hours per day for 10 to 50 days without severe adverse effects [Largent 1961].
| Revised IDLH: 30 ppm [Unchanged] Basis for revised IDLH: Based on acute inhalation toxicity data in humans [Deichmann and Gerarde 1969; Largent 1961] and animals [Machle et al. 1934], the original IDLH for hydrogen fluoride (30 ppm) is not being revised at this time. |
REFERENCES:
1. Darmer KI Jr, Haun CC, MacEwen JD [1972]. The acute inhalation toxicology of chlorine pentafluoride. Am Ind Hyg Assoc J 33:661-668.
2. Deichmann WB, Gerarde HW [1969]. Hydrofluoric acid (hydrogen fluoride, HF). In: Toxicology of drugs and chemicals. New York, NY: Academic Press, Inc., pp. 317-318.
3. Largent EJ [1961]. Fluorosis. The health aspects of fluorine compounds. Columbus, OH: Ohio State University Press, pp. 34-39, 43-48.
4. MacEwen JD, Vernot EH [1970]. Toxic hazards research unit annual report: 1970. Wright-Patterson Air Force Base, OH: Aerospace Medical Research Laboratory, AMRL-TR-70-77.
5. Machle W, Thamann F, Kitzmiller K, Cholak J [1934]. The effects of the inhalation of hydrogen fluoride. I. The response following exposure to high concentrations. J Ind Hyg Toxicol 16(2):129-145.
6. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 842.
7. Smyth HF Jr [1966]. Military and space short-term inhalation standards. Arch Environ Health 12:488-490.
8. ten Berge WF, Zwart A, Appelman LM [1986]. Concentration-time mortality response relationship of irritant and systematically acting vapours and gases. J Haz Mat 13:301-309.
9. Treon JF, Dutra FR, Cappel J, Sigmon H, Younker W [1950]. Toxicity of sulfuric acid mist. AMA Arch Ind Hyg Occup Med 2:716-734.
10. Wohlslagel J, Dipasquale LC, Vernot EH [1976]. Toxicity of solid rocket motor exhaust: effects of Hcl, HF, and alumina on rodents. J Combustion Toxicol 3:61-70.