NIOSH Publication No. 2005-151:

NIOSH Pocket Guide to Chemical Hazards

September 2005

Diacetone alcohol

CAS
123-42-2

CH3COCH2C(CH3)2OH

RTECS
SA9100000
Synonyms & Trade Names

Diacetone, 4-Hydroxy-4-methyl-2-pentanone, 2-Methyl-2-pentanol-4-one
DOT ID & Guide
1148 / 129

Exposure
Limits

NIOSH REL: TWA 50 ppm (240 mg/m3)
OSHA PEL: TWA 50 ppm (240 mg/m3)
IDLH
1800 ppm [10%LEL] See: 123422
Conversion
1 ppm = 4.75 mg/m3
Physical Description
Colorless liquid with a faint, minty odor.
MW: 116.2
BP: 334°F
FRZ: -47°F
Sol: Miscible
VP: 1 mmHg
IP: ?

Sp.Gr: 0.94
Fl.P: 125°F
UEL: 6.9%
LEL: 1.8%

Class II Combustible Liquid: Fl.P. at or above 100F and below 140F.
Incompatibilities & Reactivities

Strong oxidizers, strong alkalis
Measurement Methods
NIOSH 1402, 1405; OSHA 7
See: NMAM or OSHA Methods
Personal Protection & Sanitation
(See protection)
Skin: Prevent skin contact
Eyes: Prevent eye contact
Wash skin: When contaminated
Remove: When wet or contaminated
Change: No recommendation

First Aid
(See procedures)
Eye: Irrigate immediately
Skin: Water flush promptly
Breathing: Respiratory support
Swallow: Medical attention immediately
Respirator Recommendations
NIOSH/OSHA
Up to 1250 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 1800 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 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
Important additional information about respirator selection
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
Irritation eyes, skin, nose, throat; corneal damage; in animals: narcosis, liver damage
Target Organs
Eyes, skin, respiratory system, central nervous system, liver
See also: INTRODUCTION   See MEDICAL TESTS: 0067