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Chemical Datasheet

CHLOROSULFONIC ACID

8 - Corrosive 6.1 - Poison Inhalation Hazard
Chemical Identifiers | Hazards | Response Recommendations | Physical Properties | Regulatory Information | Alternate Chemical Names

Chemical Identifiers

The Chemical Identifier fields include common identification numbers, the NFPA diamond, U.S. Department of Transportation hazard labels, and a general description of the chemical. The information in CAMEO Chemicals comes from a variety of data sources.
CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 7790-94-5   (CHLOROSULFONIC ACID)
  • Corrosive
  • Poison Inhalation Hazard
NIOSH Pocket Guide International Chem Safety Card
none
NFPA 704
Diamond Hazard Value Description
0
4 2
W ox
Blue Health 4 Can be lethal.
Red Flammability 0 Will not burn under typical fire conditions.
Yellow Instability 2 Readily undergoes violent chemical changes at elevated temperatures and pressures.
White Special W
OX
Reacts violently or explosively with water.
Possesses oxidizing properties.
(NFPA, 2010)
General Description
A colorless to yellow colored fuming liquid with a pungent odor. Density 14.7 lb / gal. Causes severe burns. Very toxic by inhalation. Corrosive to metals.

Hazards

The Hazard fields include special hazard alerts, air and water reactions, fire hazards, health hazards, a reactivity profile, and details about reactive groups assignments and potentially incompatible absorbents. The information in CAMEO Chemicals comes from a variety of data sources.
Reactivity Alerts
Air & Water Reactions
Fumes in air. Reacts exothermically and violently with water producing sulfuric acid, hydrochloric acid, and large quantities of dense white acid fumes [Merck, 11th ed., 1989]. Contact with water and metal produces explosive hydrogen gas (USCG, 1999). Chlorosulfonic acid reacts vigorously with water to generate gaseous HCl. Based on a scenario where the chemical is spilled into an excess of water (at least 5 fold excess of water), half of the maximum theoretical yield of Hydrogen Chloride gas will be created in 0.04 minutes. Experimental details are in the following: "Development of the Table of Initial Isolation and Protective Distances for the 2008 Emergency Response Guidebook", ANL/DIS-09-2, D.F. Brown, H.M. Hartmann, W.A. Freeman, and W.D. Haney, Argonne National Laboratory, Argonne, Illinois, June 2009.
Fire Hazard
Special Hazards of Combustion Products: Decomposes into irritating and toxic gases

Behavior in Fire: Although nonflammable, it may ignite other combustibles. Contact with water AND metal produces explosive hydrogen gas. (USCG, 1999)
Health Hazard
INHALATION: vapor extremely irritating to lungs and mucous membranes. Vapor has such a sharp and pentrating odor that inhalation of severely toxic quantities is unlikely unless it is impossible to escape the fumes. CONTACT WITH EYES OR SKIN: liquid acid will severely burn body tissue. (USCG, 1999)
Reactivity Profile
CHLOROSULFONIC ACID is a strong oxidizing acid. Reacts violently with water, strong mineral acids and bases, alcohols, finely dispersed organic matter. Dangerously incompatible with combustible materials, nitrates, chlorates, metallic powders, carbides, picrates, and fulminates. Undergoes possibly violent reactions with acetic acid, acetic anhydride, acetonitrile, acrolein, acrylic acid, acrylonitrile, alkali, allyl alcohol, allyl chloride, ammonium hydroxide, aniline, butyraldehyde, cresol, cumene, diethyleneglycol methyl ether, diisopropyl ether, diphenyl ether, ethyl acetate, ethyl acrylate, ethylene chlorohydrin, ethylenediamine, ethylene glycol, glyoxal, hydrocarbons (hexane, heptane), hydrogen peroxide, isoprene, powdered metals, methyl ethyl ketone, propylene oxide, vinyl acetate. When heated to decomposition, it emits toxic fumes of hydrogen chloride and oxides of sulfur [Sax, 9th ed., 1996, p. 831]. Reaction with phosphorus accelerates out of control and culminates in an explosion [Heumann, K. et al., Ber., 1882, 15, p. 417]. Mixing chlorosulfuric acid and 98% sulfuric acid may evolve HCl [Subref: Anon, Loss Prev. Bull. 1977, (013), 2-3].
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. More info about absorbents, including situations to watch out for...

Response Recommendations

The Response Recommendation fields include isolation and evacuation distances, as well as recommendations for firefighting, non-fire response, protective clothing, and first aid. The information in CAMEO Chemicals comes from a variety of data sources.
Isolation and Evacuation
Excerpt from ERG Guide 137 [Substances - Water-Reactive - Corrosive]:

As an 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: See ERG Table 1 - Initial Isolation and Protective Action Distances on the UN/NA 1754 datasheet.

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, 2016)
Firefighting
Excerpt from ERG Guide 137 [Substances - Water-Reactive - Corrosive]:

When material is not involved in fire, do not use water on material itself.

SMALL FIRE: Dry chemical or CO2. Move containers from fire area if you can do it without risk.

LARGE FIRE: Flood fire area with large quantities of water, while knocking down vapors with water fog. If insufficient water supply: knock down vapors only.

FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Cool containers with flooding quantities of water until well after fire is out. Do not get water inside containers. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. (ERG, 2016)
Non-Fire Response
Excerpt from ERG Guide 137 [Substances - Water-Reactive - Corrosive]:

Fully encapsulating, vapor-protective clothing should be worn for spills and leaks with no fire. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Use water spray to reduce vapors; do not put water directly on leak, spill area or inside container. Keep combustibles (wood, paper, oil, etc.) away from spilled material.

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. Prevent entry into waterways, sewers, basements or confined areas. (ERG, 2016)
Protective Clothing
Acid-proof goggles or a rubber hood, long rubber gloves, rubber shoes, long rubber apron, shirt and trousers of wool or acrylic fiber, and a hat with a brim. For emergency use involving considerable exposure, a complete rubber suit with hood, gloves and boots of rubber should be used. In case of fire use self-contained breathing apparatus. (USCG, 1999)
DuPont Tychem® Suit Fabrics
Tychem® Fabric Legend
QS = Tychem 2000 SFR
QC = Tychem 2000
SL = Tychem 4000
C3 = Tychem 5000
TF = Tychem 6000
TP = Tychem 6000 FR
BR = Tychem 9000
RC = Tychem RESPONDER® CSM
TK = Tychem 10000
RF = Tychem 10000 FR
Testing Details
The fabric permeation data was generated for DuPont by independent testing laboratories using ASTM F739, EN369, EN 374-3, EN ISO 6529 (method A and B) or ASTM D6978 test methods. Normalized breakthrough times (the time at which the permeation rate is equal to 0.1 µg/cm2/min) reported in minutes. All liquid chemicals have been tested between approximately 20°C and 27°C unless otherwise stated. A different temperature may have significant influence on the breakthrough time; permeation rates typically increase with temperature. All chemicals have been tested at a concentration of greater than 95% unless otherwise stated. Unless otherwise stated, permeation was measured for single chemicals. The permeation characteristics of mixtures can deviate considerably from the permeation behavior of the individual chemicals. Chemical warfare agents (Lewisite, Sarin, Soman, Sulfur Mustard, Tabun and VX Nerve Agent) have been tested at 22°C and 50% relative humidity per military standard MIL-STD-282.
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP BR RC TK RF
Chlorosulfonic acid (>95%) 7790-94-5 Liquid >480 330 >480 17 180 >480 >480 180
> indicates greater than.
A blank cell indicates the fabric has not been tested. The fabric may or may not offer barrier.

Special Warnings from DuPont

  1. Serged and bound seams are degraded by some hazardous liquid chemicals, such as strong acids, and should not be worn when these chemicals are present.
  2. CAUTION: This information is based upon technical data that DuPont believes to be reliable. It is subject to revision as additional knowledge and experience are gained. DuPont makes no guarantee of results and assumes no obligation or liability...
    ... in connection with this information. It is the user's responsibility to determine the level of toxicity and the proper personal protective equipment needed. The information set forth herein reflects laboratory performance of fabrics, not complete garments, under controlled conditions. It is intended for informational use by persons having technical skill for evaluation under their specific end-use conditions, at their own discretion and risk. Anyone intending to use this information should first verify that the garment selected is suitable for the intended use. In many cases, seams and closures have shorter breakthrough times and higher permeation rates than the fabric. Please contact DuPont for specific data. If fabric becomes torn, abraded or punctured, or if seams or closures fail, or if attached gloves, visors, etc. are damaged, end user should discontinue use of garment to avoid potential exposure to chemical. Since conditions of use are outside our control, we make no warranties, express or implied, including, without limitation, no warranties of merchantability or fitness for a particular use and assume no liability in connection with any use of this information. This information is not intended as a license to operate under or a recommendation to infringe any patent or technical information of DuPont or others covering any material or its use.

(DuPont, 2018)

First Aid
Call a physician in all cases.

INHALATION: remove victim to fresh air; if he is not breathing, apply artificial respiration; give oxygen if breathing is difficult; do NOT induce vomiting.

SKIN: flush with plenty of water for at least 15 min. while removing contaminated clothing and shoes. (USCG, 1999)

Physical Properties

The Physical Property fields include properties such as vapor pressure and boiling point, as well as explosive limits and toxic exposure thresholds. The information in CAMEO Chemicals comes from a variety of data sources.
Chemical Formula:
  • ClHO3S
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: Not flammable (USCG, 1999)
Melting Point: -112 ° F (USCG, 1999)
Vapor Pressure: 1.55 mm Hg (USCG, 1999)
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 1.75 at 68 ° F (USCG, 1999)
Boiling Point: 311 ° F at 760 mm Hg (USCG, 1999)
Molecular Weight: 116.53 (USCG, 1999)
Water Solubility: data unavailable
Ionization Potential: data unavailable
IDLH: data unavailable

AEGLs (Acute Exposure Guideline Levels)

Interim AEGLs for Chlorosulfonic acid (7790-94-5)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes 0.1 mg/m3 4.4 mg/m3 45 mg/m3
30 minutes 0.1 mg/m3 4.4 mg/m3 31 mg/m3
60 minutes 0.1 mg/m3 4.4 mg/m3 25 mg/m3
4 hours 0.1 mg/m3 4.4 mg/m3 6.1 mg/m3
8 hours 0.1 mg/m3 4.4 mg/m3 6.1 mg/m3
(NAC/NRC, 2017)

ERPGs (Emergency Response Planning Guidelines)

Chemical ERPG-1 ERPG-2 ERPG-3
Chlorosulfonic Acid (7790-94-5) 2 mg/m3 star-in-circle icon indicates that odor should be detectable near ERPG-1. 10 mg/m3 30 mg/m3
star-in-circle icon indicates that odor should be detectable near ERPG-1.
(AIHA, 2016)

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Chlorosulfonic acid; (Chlorosulfuric acid) (7790-94-5) 0.1 mg/m3 4.4 mg/m3 25 mg/m3
(DOE, 2016)

Regulatory Information

The Regulatory Information fields include information from the U.S. Environmental Protection Agency's Title III Consolidated List of Lists, the U.S. Department of Homeland Security's Chemical Facility Anti-Terrorism Standards, and the U.S. Occupational Safety and Health Administration's Process Safety Management of Highly Hazardous Chemicals Standard List (see more about these data sources).

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
Chlorosulfonic acid 7790-94-5 1000 pounds

(EPA List of Lists, 2015)

DHS 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
Chlorosulfonic acid 7790-94-5 ACG APA sabotage/ contamination

(DHS, 2007)

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names

This section provides a listing of alternate names for this chemical, including trade names and synonyms.