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

CAS number: 108–94–1

NIOSH REL: 25 ppm (100 mg/m3) TWA [skin]

Current OSHA PEL: 50 ppm (200 mg/m3) TWA

1989 OSHA PEL: 25 ppm (100 mg/m3) TWA [skin]

1993-1994 ACGIH TLV: 25 ppm (100 mg/m3) TWA [skin]

Description of Substance: Water-white to pale-yellow liquid with a peppermint- or acetone-like odor.

LEL(@212 F): 1.1% (10% LEL(@212 F), 1,100 ppm)

Original (SCP) IDLH: 5,000 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by AIHA [1965] that a 4-hour exposure of rats to 4,000 ppm did not produce death but 8,000 ppm caused anesthesia and death [Smyth 1956]. In addition, Patty [1963] reported that typical narcotic symptoms have been observed in guinea pigs exposed for 6 hours to 4,000 ppm [Specht et al. 1940].

Short-term exposure guidelines: None developed


Lethal concentration data:






Adjusted 0.5-hr







Gupta et al. 1979

NPIRI 1974

Smyth 1956



LC100: 4,000




1.5 hr

4 hr

4 hr

6,776 ppm (1.44)

16,000 ppm (2.0)

8,000 ppm (2.0)

678 ppm

1,600 ppm

800 ppm

Other animal data: RD50 (mouse), 756 ppm [DeCeaurriz et al. 1981].

Human data: It has been reported that exposure to 75 ppm for 3 to 5 minutes has resulted in pronounced irritation of the eyes, nose, and throat [Nelson et al. 1943].

Revised IDLH: 700 ppm

Basis for revised IDLH: The revised IDLH for cyclohexanone is 700 ppm based on acute inhalation toxicity data in animals [Gupta et al. 1979; Smyth 1956].



1. AIHA [1965]. Cyclohexanone. In: Hygienic guide series. Am Ind Hyg Assoc J 26:630-633.

2. DeCeaurriz JC, Micillino JC, Bonnet P, Guenier JP [1981]. Sensory irritation caused by various industrial airborne chemicals. Toxicol Lett 9:137-143.

3. Gupta PK, Lawrence WH, Turner JE, Autian J [1979]. Toxicological aspects of cyclohexanone. Toxicol Appl Pharmacol 49:525-533.

4. Nelson KW, Ege JF Jr, Ross M, Woodman LE, Silverman L [1943]. Sensory response to certain industrial solvent vapors. J Ind Hyg Toxicol 25(7):282-285.

5. NPIRI [1974]. Raw materials data handbook, physical and chemical properties, fire hazard and health hazard data. Vol. 1. Organic solvents. Bethlehem, PA: National Printing Ink Research Institute, p. 18.

6. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1767.

7. Smyth HF Jr [1956]. Improved communication: hygienic standards for daily inhalation. Am Ind Hyg Assoc Q 17(2):129-185.

8. Specht H, Miller JW, Valaer PJ, Sayers RR [1940]. Acute response of guinea pigs to the inhalation of ketone vapors. Washington, DC: U.S. Government Printing Office, Federal Security Agency, U.S. Public Health Service, NIH Bulletin 176:1-66.

Page last reviewed: December 4, 2014