# NIOSH Pocket Guide to Chemical Hazards
Isophorone | CAS 78-59-1
C9H14O | RTECS GW7700000
Synonyms & Trade Names Isoacetophorone; 3,5,5-Trimethyl-2-cyclohexenone; 3,5,5-Trimethyl-2-cyclo-hexen-1-one | DOT ID & Guide 1993 128 (combustible liquid, n.o.s.)
Exposure Limits | NIOSH REL: TWA 4 ppm (23 mg/m3)
OSHA PEL†: TWA 25 ppm (140 mg/m3)
IDLH 200 ppm | Conversion 1 ppm = 5.65 mg/m3
Physical Description Colorless to white liquid with a peppermint-like odor.
MW: 138.2 | BP: 419°F | FRZ: 17°F | Sol: 1%
VP: 0.3 mmHg | IP: 9.07 eV |  | Sp.Gr: 0.92
Fl.P: 184°F | UEL: 3.8% | LEL: 0.8% |
Class IIIA Combustible Liquid: Fl.P. at or above 140°F and below 200°F.
Incompatibilities & Reactivities Oxidizers, strong alkalis, amines
Measurement Methods NIOSH 2508; OSHA 7
Personal Protection & Sanitation Skin: Prevent skin contact Eyes: Prevent eye contact Wash skin: When contaminated Remove: When wet or contaminated Change: No recommendation Provide: Eyewash | First Aid (See procedures) Eye: Irrigate immediately Skin: Soap wash promptly Breathing: Respiratory support Swallow: Medical attention immediately
Respirator Recommendations NIOSH Up to 40 ppm: (APF = 10) Any chemical cartridge respirator with organic vapor cartridge(s)*/(APF = 10) Any supplied-air respirator* Up to 100 ppm: (APF = 25) Any supplied-air respirator operated in a continuous-flow mode*/(APF = 25) Any powered, air-purifying respirator with organic vapor cartridge(s)* Up to 200 ppm: (APF = 50) Any chemical cartridge respirator with a full facepiece and organic vapor cartridge(s)/(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister/(APF = 50) Any powered, air-purifying respirator with a tight-fitting facepiece and organic vapor cartridge(s)*/(APF = 50) Any supplied-air respirator that has a tight-fitting facepiece and is operated in a continuous-flow mode*/(APF = 50) Any self-contained breathing apparatus with a full facepiece/(APF = 50) Any supplied-air respirator with a full facepiece Emergency or planned entry into unknown concentrations or IDLH conditions: (APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode/(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus Escape: (APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister/Any appropriate escape-type, self-contained breathing apparatus
Exposure Routes inhalation, ingestion, skin and/or eye contact
Symptoms Irritation eyes, nose, throat; headache, nausea, dizziness, lassitude (weakness, exhaustion), malaise (vague feeling of discomfort), narcosis; dermatitis; in animals: kidney, liver damage
Target Organs Eyes, skin, respiratory system, central nervous system, liver, kidneys
See also: INTRODUCTION