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Chemical Datasheet

SODIUM HYDROXIDE SOLUTION

8 - Corrosive

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 1310-73-2
  • 1824
  • Corrosive
  • CSS
NIOSH Pocket Guide International Chem Safety Card
Sodium hydroxide
  • SODIUM HYDROXIDE
NFPA 704
Diamond Hazard Value Description
0
3 1
Blue Health 3 Can cause serious or permanent injury.
Red Flammability 0 Will not burn under typical fire conditions.
Yellow Instability 1 Normally stable but can become unstable at elevated temperatures and pressures.
White Special
(NFPA, 2010)
General Description
A colorless liquid. More dense than water. Contact may severely irritate skin, eyes, and mucous membranes. Toxic by ingestion. Corrosive to metals and tissue.

Hazards

Reactivity Alerts
none
Air & Water Reactions
Slowly absorbs carbon dioxide from the air to give solid products as crusts or precipitates. Water soluble. Dilution with water liberates heat, possibly enough to cause local boiling and spattering.
Fire Hazard
Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. For electric vehicles or equipment, ERG Guide 147 (lithium ion batteries) or ERG Guide 138 (sodium batteries) should also be consulted. (ERG, 2020)
Health Hazard
Causes severe burns of eyes, skin, and mucous membranes. (USCG, 1999)
Reactivity Profile
SODIUM HYDROXIDE SOLUTION refers to an aqueous solution of sodium hydroxide. Strongly basic. Reacts rapidly and exothermically with organic and inorganic acids, with organic and inorganic acid anhydrides, including oxides of nonmetals such as sulfur dioxide, sulfur trioxide, phosphorus trioxide, phosphorus pentaoxide, and with organic and inorganic acid chlorides. May react explosively with maleic anhydride [MCA Case History 622 1960]. Attacks aluminum and zinc with evolution of hydrogen, a flammable gas. May initiate polymerization in polymerizable organic materials: a violent polymerization results if acetaldehyde contacts alkaline materials such as sodium hydroxide; an extremely violent polymerization results from contact of acrolein with alkaline materials such as sodium hydroxide [Chem. Safety Data Sheet SD-85 1961]. A violent explosion resulted when a quantity of pentol was accidentally brought in contact with a caustic cleaning solution chemically similar to aqueous sodium hydroxide [MCA Case History 363 1964]. Aqueous solutions of reducing sugars other than sucrose, when heated (above 84°C.), evolve toxic levels of carbon monoxide in the presence of alkalis or alkaline salts, such as sodium phosphate (also potassium hydroxide, sodium hydroxide, calcium hydroxide, etc.) [Bretherick 5th ed. 1995]. Hot and/or concentrated NaOH can cause hydroquinone to decompose exothermically at elevated temperature. (NFPA Pub. 491M, 1975, 385)
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

Use caution: Liquids with this reactive group classification have been known to react with the absorbents listed below.

Response Recommendations

Isolation and Evacuation
Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.

FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2020)
Firefighting
Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

SMALL FIRE: Dry chemical, CO2 or water spray.

LARGE FIRE: Dry chemical, CO2, alcohol-resistant foam or water spray. If it can be done safely, move undamaged containers away from the area around the fire. Dike runoff from fire control for later disposal.

FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Do not get water inside containers. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. (ERG, 2020)
Non-Fire Response
Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. DO NOT GET WATER INSIDE CONTAINERS. (ERG, 2020)
Protective Clothing
Wide-brimmed hat; safety goggles with rubber side shields; tight-fitting cotton clothing; rubber gloves under shirt cuffs; rubber boots and apron. (USCG, 1999)
DuPont Tychem® Suit Fabrics
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP RC TK RF
Caustic soda (50% at 50°C) 1310-73-2 Liquid >480
Caustic soda (50%) 1310-73-2 Liquid >480 >480 >480 >480 >480 >480 >480 >480 >480
Sodium hydroxide (50% at 50°C) 1310-73-2 Liquid >480
Sodium hydroxide (50%) 1310-73-2 Liquid >480 >480 >480 >480 >480 >480 >480 >480 >480
> indicates greater than.

Special Warning from DuPont: Tychem® and Tyvek® fabrics should not be used around heat, flames, sparks or in potentially flammable or explosive environments. Only...

(DuPont, 2022)

First Aid
(Act quickly)

EYES: flush with water at once for at least 15 min.

SKIN: flush with water, then rinse with dilute vinegar (acetic acid).

INGESTION: give water and milk. Do NOT induce vomiting. Call physician at once, even when injury seems to be slight. (USCG, 1999)

Physical Properties

Chemical Formula:
  • NaOH (aqueous)
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: Not flammable (USCG, 1999)
Melting Point: data unavailable
Vapor Pressure: data unavailable
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 1.5 at 68°F (USCG, 1999)
Boiling Point: greater than 266°F at 760 mmHg (USCG, 1999)
Molecular Weight: data unavailable
Water Solubility: data unavailable
Ionization Energy/Potential: data unavailable
IDLH: 10 mg/m3 [From NPG: Sodium hydroxide] (NIOSH, 2022)

AEGLs (Acute Exposure Guideline Levels)

No AEGL information available.

ERPGs (Emergency Response Planning Guidelines)

Chemical ERPG-1 ERPG-2 ERPG-3
Sodium Hydroxide (1310-73-2) 0.5 mg/m3 5 mg/m3 50 mg/m3
(AIHA, 2020)

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Sodium hydroxide (1310-73-2) 0.5 mg/m3 5 mg/m3 50 mg/m3
(DOE, 2018)

Regulatory Information

EPA Consolidated List of Lists

Regulatory Name CAS Number/
313 Category Code
EPCRA 302
EHS TPQ
EPCRA 304
EHS RQ
CERCLA RQ EPCRA 313
TRI
RCRA
Code
CAA 112(r)
RMP TQ
Sodium hydroxide 1310-73-2 1000 pounds

(EPA List of Lists, 2022)

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

No regulatory information available.

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names