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Chemical Datasheet

HYDROCHLORIC ACID, SOLUTION

8 - Corrosive

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 7647-01-0   (HYDROGEN CHLORIDE)
  • 1789
  • Corrosive
  • HCL
NIOSH Pocket Guide International Chem Safety Card
Hydrogen chloride
  • HYDROGEN CHLORIDE
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
Colorless watery liquid with a sharp, irritating odor. Consists of hydrogen chloride, a gas, dissolved in water. Sinks and mixes with water. Produces irritating vapor. (USCG, 1999)

Hazards

Reactivity Alerts
Air & Water Reactions
An aqueous solution. Dilution may generate heat. Fumes in air.
Fire Hazard
Special Hazards of Combustion Products: Toxic and irritating vapors are generated when heated. (USCG, 1999)
Health Hazard
Inhalation of fumes results in coughing and choking sensation, and irritation of nose and lungs. Liquid causes burns. (USCG, 1999)
Reactivity Profile
HYDROCHLORIC ACID is an aqueous solution of hydrogen chloride, an acidic gas. Reacts exothermically with organic bases (amines, amides) and inorganic bases (oxides and hydroxides of metals). Reacts exothermically with carbonates (including limestone and building materials containing limestone) and hydrogen carbonates to generate carbon dioxide. Reacts with sulfides, carbides, borides, and phosphides to generate toxic or flammable gases. Reacts with many metals (including aluminum, zinc, calcium, magnesium, iron, tin and all of the alkali metals) to generate flammable hydrogen gas. Reacts violently with acetic anhydride, 2-aminoethanol, ammonium hydroxide, calcium phosphide, chlorosulfonic acid, 1,1-difluoroethylene, ethylenediamine, ethyleneimine, oleum, perchloric acid, b-propiolactone, propylene oxide, silver perchlorate/carbon tetrachloride mixture, sodium hydroxide, uranium(IV) phosphide, vinyl acetate, calcium carbide, rubidium carbide, cesium acetylide, rubidium acetylide, magnesium boride, mercury(II) sulfate [Lewis]. Mixtures with concentrated sulfuric acid can evolve toxic hydrogen chloride gas at a dangerous rate. Undergoes a very energetic reaction with calcium phosphide [Mellor 8:841(1946-1947)].
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

Response Recommendations

Isolation and Evacuation
Excerpt from ERG Guide 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

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 tank car or highway tank 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, 2024)
Firefighting
Excerpt from ERG Guide 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

Note: Some foams will react with the material and release corrosive/toxic gases.

SMALL FIRE: CO2 (except for Cyanides), dry chemical, dry sand, alcohol-resistant foam.

LARGE FIRE: Water spray, fog or alcohol-resistant foam. If it can be done safely, move undamaged containers away from the area around the fire. Avoid aiming straight or solid streams directly onto the product. Dike runoff from fire control for later disposal.

FIRE INVOLVING TANKS, RAIL TANK CARS OR HIGHWAY TANKS: 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 in direct contact with flames. (ERG, 2024)
Non-Fire Response
Excerpt from ERG Guide 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. A vapor-suppressing foam may be used to reduce vapors. DO NOT GET WATER INSIDE CONTAINERS. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material. Prevent entry into waterways, sewers, basements or confined areas.

SMALL SPILL: Cover with DRY earth, DRY sand or other non-combustible material followed with plastic sheet to minimize spreading or contact with rain. Use clean, non-sparking tools to collect material and place it into loosely covered plastic containers for later disposal. (ERG, 2024)
Protective Clothing
Excerpt from ERG Guide 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer when there is NO RISK OF FIRE. Structural firefighters' protective clothing provides thermal protection but only limited chemical protection. (ERG, 2024)
DuPont Tychem® Suit Fabrics
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP RC TK RF
Hydrochloric acid (37%) 7647-01-0 Liquid 54 140 >480 >480 >480 >480 >480 >480 >480
Hydrogen chloride (-90°C, liquid) 7647-01-0 Liquid >180
Hydrogen chloride (gaseous) 7647-01-0 Vapor imm >480 >480 >480 >480 >480 >480 >480
> indicates greater than.
"imm" indicates immediate; having a normalized breakthrough time of 10 minutes or less.

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, 2024)

First Aid
INHALATION: remove person to fresh air; keep him warm and quiet and get medical attention immediately; start artificial respiration if breathing stops.

INGESTION: have person drink water or milk; do NOT induce vomiting.

EYES: immediately flush with plenty of water for at least 15 min. and get medical attention; continue flushing for another 15 min. if physician does not arrive promptly.

SKIN: immediately flush skin while removing contaminated clothing; get medical attention promptly; use soap and wash area for at least 15 min. (USCG, 1999)

Physical Properties

Chemical Formula:
  • HCl (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: 413.6 mmHg (USCG, 1999)
Vapor Density (Relative to Air): data unavailable
Specific Gravity: data unavailable
Boiling Point: 123°F at 760 mmHg (USCG, 1999)
Molecular Weight: 36.46 (USCG, 1999)
Water Solubility: data unavailable
Ionization Energy/Potential: 12.74 eV [From NPG: Hydrogen chloride] (NIOSH, 2024)
IDLH: 50 ppm [From NPG: Hydrogen chloride] (NIOSH, 2024)

AEGLs (Acute Exposure Guideline Levels)

Final AEGLs for Hydrogen chloride (7647-01-0)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes 1.8 ppm 100 ppm 620 ppm
30 minutes 1.8 ppm 43 ppm 210 ppm
60 minutes 1.8 ppm 22 ppm 100 ppm
4 hours 1.8 ppm 11 ppm 26 ppm
8 hours 1.8 ppm 11 ppm 26 ppm
(NAC/NRC, 2024)

ERPGs (Emergency Response Planning Guidelines)

Chemical ERPG-1 ERPG-2 ERPG-3
Hydrogen Chloride (7647-01-0) 3 ppm star-in-circle icon indicates that odor should be detectable near ERPG-1. 20 ppm 150 ppm
star-in-circle icon indicates that odor should be detectable near ERPG-1.
(AIHA, 2022)

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Hydrogen chloride; (Hydrochloric acid) (7647-01-0) 1.8 ppm 22 ppm 100 ppm
(DOE, 2024)

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
Hydrochloric acid 7647-01-0 5000 pounds
Hydrochloric acid (aerosol forms only) 7647-01-0 5000 pounds 313
Hydrochloric acid (conc 37% or greater) 7647-01-0 5000 pounds 15000 pounds
Hydrogen chloride (anhydrous) 7647-01-0 500 pounds 5000 pounds 5000 pounds X 5000 pounds
Hydrogen chloride (gas only) 7647-01-0 500 pounds 5000 pounds 5000 pounds X 5000 pounds

(EPA List of Lists, 2024)

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

RELEASE THEFT SABOTAGE
Chemical of Interest CAS Number Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Hydrochloric acid (conc. 37% or greater) 7647-01-0 37.00 % 15000 pounds toxic
Hydrogen chloride (anhydrous) 7647-01-0 1.00 % 5000 pounds toxic ACG 500 pounds WME

(CISA, 2007)

OSHA Process Safety Management (PSM) Standard List

Chemical Name CAS Number Threshold Quantity (TQ)
Hydrochloric Acid, Anhydrous 7647-01-0 5000 pounds
Hydrogen Chloride 7647-01-0 5000 pounds

(OSHA, 2019)

Alternate Chemical Names