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Sodium hydroxide

Synonyms & Trade Names
Caustic soda, Lye, Soda lye, Sodium hydrate
CAS No.
1310-73-2
RTECS No.
WB4900000
DOT ID & Guide
1823 154 (dry, solid)
1824 154 (solution)
Formula
NaOH
Conversion
IDLH
10 mg/m3
See: 1310732
Exposure Limits
NIOSH REL
: C 2 mg/m3
OSHA PEL
†: TWA 2 mg/m3
Measurement Methods

NIOSH 7401
See: NMAM or OSHA Methods
Physical Description
Colorless to white, odorless solid (flakes, beads, granular form).
MW:
40.0
BP:
2534°F		 MLT: 605°F
Sol:
111%
VP:
0 mmHg (approx)
IP:
NA
Sp.Gr:
2.13
Fl.P:
NA
UEL:
NA
LEL:
NA
Noncombustible Solid, but when in contact with water may generate sufficient heat to ignite combustible materials.
Incompatibilities & Reactivities
Water; acids; flammable liquids; organic halogens; metals such as aluminum, tin & zinc; nitromethane [Note: Corrosive to metals.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, mucous membrane; pneumonitis; eye, skin burns; temporary loss of hair
Target Organs
Eyes, skin, respiratory system
Personal Protection/Sanitation
(See protection codes)
Skin: Prevent skin contact
Eyes: Prevent eye contact
Wash skin: When contaminated
Remove: When wet or contaminated
Change: Daily
Provide: Eyewash, Quick drench
First Aid
(See procedures)
Eye: Irrigate immediately
Skin: Water flush immediately
Breathing: Respiratory support
Swallow: Medical attention immediately
Respirator Recommendations

NIOSH/OSHA

Up to 10 mg/m3:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode£
(APF = 50) Any air-purifying, full-facepiece respirator with an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters.
(APF = 25) Any powered, air-purifying respirator with a high-efficiency particulate filter.£
(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 with an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters.
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also: INTRODUCTION   See ICSC CARD: 0360   See MEDICAL TESTS: 0210
 
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