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2-Butanone

Synonyms & Trade Names
Ethyl methyl ketone, MEK, Methyl acetone, Methyl ethyl ketone
CAS No.
78-93-3
RTECS No.
EL6475000
DOT ID & Guide
1193 127
Formula
CH3COCH2CH3
Conversion
1 ppm = 2.95 mg/m3
IDLH
3000 ppm
See: 78933
Exposure Limits
NIOSH REL
: TWA 200 ppm (590 mg/m3) ST 300 ppm (885 mg/m3)
OSHA PEL
†: TWA 200 ppm (590 mg/m3)
Measurement Methods

NIOSH 2500 , 2555 , 3800;
OSHA 16 , 84 , 1004
See: NMAM or OSHA Methods
Physical Description
Colorless liquid with a moderately sharp, fragrant, mint- or acetone-like odor.
MW:
72.1
BP:
175°F
FRZ:
-123°F
Sol:
28%
VP:
78 mmHg
IP:
9.54 eV
Sp.Gr:
0.81
Fl.P:
16°F		 UEL(200°F): 11.4% LEL(200°F): 1.4%
Class IB Flammable Liquid: Fl.P. below 73°F and BP at or above 100°F.
Incompatibilities & Reactivities
Strong oxidizers, amines, ammonia, inorganic acids, caustics, isocyanates, pyridines
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, nose; headache; dizziness; vomiting; dermatitis
Target Organs
Eyes, skin, respiratory system, central nervous system
Personal Protection/Sanitation
(See protection codes)
Skin: Prevent skin contact
Eyes: Prevent eye contact
Wash skin: When contaminated
Remove: When wet (flammable)
Change: No recommendation
Provide: Eyewash
First Aid
(See procedures)
Eye: Irrigate immediately
Skin: Water wash immediately
Breathing: Fresh air
Swallow: Medical attention immediately
Respirator Recommendations

NIOSH/OSHA

Up to 3000 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)£
(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 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

See also: INTRODUCTION   See ICSC CARD: 0179   See MEDICAL TESTS: 0133
 

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