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        Syndicate





Sodium hydroxide																				Related Pages
Synonyms & Trade Names
			Caustic soda, Lye [Sodium hydroxide], Soda lye, Sodium hydrate
CAS No.
			1310-73-2
	RTECS No.
			WB4900000
	DOT ID & Guide
			1823 154(dry, solid)1824 154(solution)

FormulaNaOH
	Conversion
	IDLH
			10 mg/m3See: 1310732

Exposure Limits
			NIOSH RELC 2 mg/m3OSHA PEL TWA 2 mg/m3See Appendix G
	Measurement Methods
			**NIOSH** 7401
					
					See: NMAM or OSHA Methods
										
Physical Description
			Colorless to white, odorless solid (flakes, beads, granular form).													
										
Molecular Weight40.0	
	Boiling Point2534°F
	Melting Point605°F
	Solubility111%
	Vapor Pressure0 mmHg (approx)
	Ionization PotentialNA											
Specific Gravity2.13	
	Flash PointNA
	Upper Explosive LimitNA
	Lower Explosive LimitNA
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
					  ICSC CARD: 0360
					  MEDICAL TESTS: 0210

			
							

			Page last reviewed:  October 30, 2019						Content
							source: 	National Institute for Occupational Safety and Health NIOSH Pocket Guide to Chemical Hazards
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Appendices
A – NIOSH Potential Occupational Carcinogens
B – Thirteen OSHA-Regulated Carcinogens
C – Supplementary Exposure Limits
D – Substances with No Established RELs
E – OSHA Respirator Requirements for Selected Chemicals
F – Miscellaneous Notes
G – 1989 Air Contaminants Update Project: Exposure Limits NOT in Effect
Type C & CE – Definitions for Type C and Type CE Respirators
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