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Carbon dioxide
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 124–38–9
NIOSH REL: 5,000 ppm (9,000 mg/m3) TWA,
30,000 ppm (54,000 mg/m3) STEL
Current OSHA PEL: 5,000 ppm (9,000 mg/m3) TWA
1989 OSHA PEL: 10,000 ppm (18,000 mg/m3) TWA,
30,000 ppm (54,000 mg/m3) STEL
1993-1994 ACGIH TLV: 5,000 ppm (9,000 mg/m3) TWA,
30,000 ppm (54,000 mg/m3) STEL
Description of Substance: Colorless, odorless gas.
LEL: . . Nonflammable Gas
Original (SCP) IDLH: 50,000 ppm
Basis for original (SCP) IDLH: The chosen IDLH is based on the statements by ACGIH [1971] that a 30-minute exposure at 50,000 ppm produces signs of intoxication, and a few minutes of exposure at 70,000 ppm and 100,000 ppm produces unconsciousness [Flury and Zernik 1931]. AIHA [1971] reported that 100,000 ppm is the atmospheric concentration immediately dangerous to life. In addition, Hunter [1975] noted that exposure to 100,000 ppm for only a few minutes can cause loss of consciousness.
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA
Lethal concentration data:
| Species | Reference | LC50(ppm) | LCLo(ppm) | Time | Adjusted 0.5-hrLC (CF) | DerivedValue |
|---|---|---|---|---|---|---|
| Human | Tab Biol Per 1933 | —– | 90,000 | 5 min | 49,500 ppm (0.55) | 4,950 ppm |
Other human data: Signs of intoxication have been produced by a 30-minute exposure at 50,000 ppm [Aero 1953], and a few minutes exposure at 70,000 to 100,000 ppm produces unconsciousness [Flury and Zernik 1931]. It has been reported that submarine personnel exposed continuously at 30,000 ppm were only slightly affected, provided the oxygen content of the air was maintained at normal concentrations [Schaefer 1951]. It has been reported that 100,000 ppm is the atmospheric concentration immediately dangerous to life [AIHA 1971] and that exposure to 100,000 ppm for only a few minutes can cause loss of consciousness [Hunter 1975].
| Revised IDLH: 40,000 ppmBasis for revised IDLH: The revised IDLH for carbon dioxide is 40,000 ppm based on acute inhalation toxicity data in humans [Aero 1953; Flury and Zernik 1931; Schaefer 1951]. |
REFERENCES:
1. ACGIH [1971]. Carbon dioxide. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, p. 39.
2. Aero Medical Association [1953]. Committee on Aviation Toxicology, Blakiston, New York.
3. AIHA [1964]. Carbon dioxide. In: Hygienic guide series. Am Ind Hyg Assoc J 25:519-521.
4. Flury F, Zernik F [1931]. Schädliche gase dämpfe, nebel, rauch- und staubarten. Berlin, Germany: Verlag von Julius Springer, pp. 218-219 (in German).
5. Hunter D [1975]. The diseases of occupations. 5th ed. London, England: Hodder and Stoughton, p. 618.
6. Schaefer KE [1951]. Studies of carbon dioxide toxicity. New London, CT: Navy Department, Bureau of Medicine and Surgery, Medical Research Laboratory, U.S. Naval Submarine Base, Vol. 10, Report No. 181, pp. 156-189.
7. Tab Biol Per [1933]; 3:231 (in German).