Carbon dioxide

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-hr LC (CF)	Derived Value
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 ppm Basis 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).