Substance profile
Chloroacetyl chloride
Chloroacetyl chloride is a liquid with a sharp, pungent, irritating odor.
01 · Identification
What Chloroacetyl chloride is
Chloroacetyl chloride is a liquid with a sharp, pungent, irritating odor. Its molecular formula is C2H2Cl2O and its molecular weight is 112.94 g/mol. It boils at 106 °C, melts at -21.7 °C.
Under the GHS it carries the signal word Danger. It is classed as corrosives.
02 · Identifiers
Chloroacetyl chloride identifiers and molecular data
Chloroacetyl chloride CAS number and EC number
Chloroacetyl chloride molecular formula and molecular weight
03 · GHS classification
Chloroacetyl chloride hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
Chloroacetyl chloride pictograms and signal word
Chloroacetyl chloride hazard class and category
| Hazard class | Category | From code | Pictogram |
|---|---|---|---|
| Acute toxicity - oral GHS chapter 3.1 | Category 3 | H301 | GHS06 |
| Acute toxicity - dermal GHS chapter 3.1 | Category 3 | H311 | GHS06 |
| Acute toxicity - inhalation GHS chapter 3.1 | Category 3 | H331 | GHS06 |
| Skin corrosion/irritation GHS chapter 3.2 | Category 1A or 1B or 1C | H314 | GHS05 |
| Specific target organ toxicity - repeated exposure GHS chapter 3.9 | Category 1 | H372 | GHS08 |
| Hazardous to the aquatic environment - acute GHS chapter 4.1 | Category 1 | H400 | GHS09 |
Where two values are shown with “or”, the hazard statement is shared by more than one category or by more than one class, and the code alone does not say which. H272, for example, belongs to oxidising liquids and to oxidising solids — the physical state decides. The binding answer for a specific entry is in the CLP Annex VI table itself.
Chloroacetyl chloride hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H331 | Toxic if inhaled. |
| H311 | Toxic in contact with skin. |
| H301 | Toxic if swallowed. |
| H372 | Causes damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. |
| H314 | Causes severe skin burns and eye damage. |
| H400 | Very toxic to aquatic life. |
Chloroacetyl chloride supplemental EU statements (EUH)
| Code | Statement |
|---|---|
| EUH014 | Reacts violently with water. |
| EUH029 | Contact with water liberates toxic gas. |
This page lists only the codes assigned to Chloroacetyl chloride. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.
Safety Data Sheet
Getting an SDS for Chloroacetyl chloride
A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of Chloroacetyl chloride issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.
04 · Precautionary statements
Chloroacetyl chloride precautionary statements
CLP Annex VI assigns 15 precautionary statements to Chloroacetyl chloride. They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.
Prevention
What to do before and during handling so the hazard never happens.
Response
What to do once exposure, spillage or fire has already happened.
Disposal
What has to happen to the contents and the empty container.
Reading the notation. … is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.
05 · Names in the regulation
Chloroacetyl chloride name in 23 EU languages
CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.
| Language | Name in CLP Annex VI Part 3 |
|---|---|
| Bulgarian български | хлороацетилхлорид |
| Spanish español | Cloruro de cloroacetilo |
| Czech čeština | chloracetylchlorid |
| Danish dansk | chloracetylchlorid |
| German Deutsch | Chloracetylchlorid α-Chloressigsäurechlorid |
| Estonian eesti | kloroatsetüülkloriid |
| Greek ελληνικά | χλωροακετυλοχλωρίδιο |
| English English | chloroacetyl chloride |
| French français | chlorure de chloroacétyle |
| Croatian hrvatski | kloracetil-klorid |
| Italian italiano | cloruro di cloroacetile |
| Latvian latviešu | hloracetilhlorīds |
| Lithuanian lietuvių | chloracetilchloridas |
| Hungarian magyar | klóracetil-klorid |
| Maltese Malti | klorur tal-kloroaċetil |
| Dutch Nederlands | chlooracetylchloride |
| Polish polski | chlorek chloroacetylu chlorek kwasu chlorooctowego |
| Portuguese português | cloreto de cloroacetilo |
| Romanian română | clorură de cloroacetil |
| Slovak slovenčina | chlóracetylchlorid |
| Slovenian slovenščina | kloroacetil klorid |
| Finnish suomi | klooriasetyylikloridi |
| Swedish svenska | kloracetylklorid |
All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.
06 · Label elements
Chloroacetyl chloride GHS label elements
Everything CLP Annex VI fixes for Chloroacetyl chloride, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
Chloroacetyl chloride
- Toxic if inhaled.
- Toxic in contact with skin.
- Toxic if swallowed.
- Causes damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
- Causes severe skin burns and eye damage.
- Very toxic to aquatic life.
- Reacts violently with water.
- Contact with water liberates toxic gas.
- Do not breathe dust/fume/gas/mist/vapours/spray.
- Do not eat, drink or smoke when using this product.
- Use only outdoors or in a well-ventilated area.
- Avoid release to the environment.
- Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/…
- IF SWALLOWED:
- IF ON SKIN:
- IF INHALED:
- Immediately call a POISON CENTER/doctor/…
- Get medical advice/attention if you feel unwell.
- Rinse mouth.
- Do NOT induce vomiting.
- Wash with plenty of water/…
- Collect spillage.
- Dispose of contents/container to …
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open Chloroacetyl chloride in the GHS label constructor →
07 · Health hazards
Chloroacetyl chloride health hazards and exposure limits
Chloroacetyl chloride hazard summary
Liquid causes second or third degree burns after short contact; [CHRIS] Corrosive to skin; [Quick CPC] Hydrolysis of chloroacetyl chloride yields chloroacetic acid and hydrogen chloride gas. It causes clinical and pathologic evidence of respiratory effects at the lowest concentrations tested in experimental animals; [ACGIH] A lachrymator; [HSDB]
Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
Chloroacetyl chloride occupational exposure limits
| Limit | Value | Source |
|---|---|---|
| PEL | none See Appendix G | The National Institute for Occupational Safety and Health (NIOSH) |
| REL | 0.05 ppm (0.2 mg/m³) | Occupational Safety and Health Administration (OSHA) |
| REL | TWA 0.05 ppm (0.2 mg/m³) | The National Institute for Occupational Safety and Health (NIOSH) |
| IDLH | 1.3 ppm (NIOSH, 2024) | CAMEO Chemicals |
| IDLH | 1.3 [ppm] | Haz-Map, Information on Hazardous Chemicals and Occupational Diseases |
| IDLH | 1.3 ppm | The National Institute for Occupational Safety and Health (NIOSH) |
These are United States values. The European Union sets its own indicative and binding limits, and the figure that applies at a given workplace is the one in the local regulation — not the one shown here.
08 · Physical and chemical properties
Chloroacetyl chloride properties
Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.
Chloroacetyl chloride boiling point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 106 °C (222.8 °F) | HSDB | |
| 106.11 °C (223 °F) | NIOSH | ||
| 105 °C (221 °F) | at 760 mmHg | CAMEO |
Chloroacetyl chloride melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | -21.7 °C (-7.1 °F) | HSDB | |
| -21.67 °C (-7 °F) | NIOSH | ||
| -22.5 °C (-8.5 °F) | CAMEO |
Chloroacetyl chloride density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 1.42 g/cm³ | NIOSH | |
| 1.4202 g/cm³ | at 20 °C | HSDB |
Chloroacetyl chloride solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | Decomposed by water | decomposes | HSDB |
| Decomposes | decomposes | NIOSH | |
| Decomposes (NIOSH, 2024) | decomposes | CAMEO |
Chloroacetyl chloride vapor pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor pressure | 19 mmHg | NIOSH | |
| 25.2 mmHg | at 25 °C | HSDB |
Chloroacetyl chloride flash point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Flash point | 100 °C (212 °F) | HSDB |
Chloroacetyl chloride lower explosive limit (LEL)
| Property | Value | Conditions | Source |
|---|---|---|---|
| Lower explosive limit (LEL) | Noncombustible Liquid | NIOSH |
Chloroacetyl chloride vapor density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor density | 3.9 (air = 1) | ICSC |
Chloroacetyl chloride odor threshold
| Property | Value | Conditions | Source |
|---|---|---|---|
| Odor threshold | An industrial hygienist was not able to detect odor at 0.011 ppm, found 0.023 ppm barely detectable, and 0.140 ppm "strong". | HSDB |
Chloroacetyl chloride critical temperature and pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Critical temperature and pressure | 307.85 °C (586.1 °F) | HSDB |
Chloroacetyl chloride corrosivity
| Property | Value | Conditions | Source |
|---|---|---|---|
| Corrosivity | ... metals (corrosive) | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Fire and explosion
Chloroacetyl chloride fire and explosion behaviour
These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.
Chloroacetyl chloride fire potential
Not combustible, but if involved in a fire decomposes to produce hydrogen chloride.
Source: Hazardous Substances Data Bank (HSDB)
10 · Handling and storage
Chloroacetyl chloride storage and handling
Chloroacetyl chloride safe storage
Separated from food and feedstuffs. See Chemical Dangers. Dry. Keep in a well-ventilated room.
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Chloroacetyl chloride storage conditions
Store under nitrogen. Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Keep away from water. Never allow product to get in contact with water during storage. Hydrolyzes readily.
Source: Hazardous Substances Data Bank (HSDB)
Chloroacetyl chloride incompatible materials
Incompatible materials: Strong oxidizing agents, strong bases, alcohols, water.
Source: Hazardous Substances Data Bank (HSDB)
Chloroacetyl chloride reactivity
CHLOROACETYL CHLORIDE reacts rapidly with water. Incompatible with strong oxidizing agents, alcohols, bases (including amines). May react vigorously or explosively if mixed with diisopropyl ether or other ethers in the presence of trace amounts of metal salts [J. Haz. Mat., 1981, 4, 291].
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Chloroacetyl chloride in the storage compatibility matrix →
11 · Transport
Chloroacetyl chloride UN number and transport classification
Transport classification is a separate system from the GHS classification above. It decides how a package is marked and how a load may be carried; it does not follow from the workplace label, and the workplace label does not follow from it. The entries below are linked by CAS number, never by name.
Chloroacetyl chloride under UN 1752 — shipping name, class and packing group
Europe · ADR 2025, Table A
| Proper shipping name (3.1.2) | Class | Classification code | PG | Labels (column 5) |
|---|---|---|---|---|
| CHLOROACETYL CHLORIDE | 6.1 | TC1 | I | |
Source: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE). Class 6.1 is “Toxic substances” (ADR 2.1.1.1).
United States · 49 CFR 172.101 Hazardous Materials Table
| Proper shipping name (column 2) | Class or division | PG | Labels (column 6) |
|---|---|---|---|
| Chloroacetyl chloride | 6.1 | I | |
Source: 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03. Class 6.1 is “Poisonous materials” (49 CFR 173.2).
12 · Questions
Chloroacetyl chloride — frequently asked questions
What is the CAS number of Chloroacetyl chloride?
The CAS number of Chloroacetyl chloride is 79-04-9. Its EC number is 201-171-6.
What is the chemical formula of Chloroacetyl chloride?
The molecular formula of Chloroacetyl chloride is C2H2Cl2O and its molecular weight is 112.94 g/mol.
What does a Chloroacetyl chloride label have to show?
Under CLP Annex VI the label for Chloroacetyl chloride carries the pictograms Skull and crossbones, Health hazard, Corrosion and Environment and the signal word is Danger.
Is Chloroacetyl chloride flammable?
CLP Annex VI assigns Chloroacetyl chloride no flammability hazard class. That is not a statement that it cannot burn: the harmonised list only records the hazards that were assessed for it. The flash point reported for it is 100 °C (212 °F) (HSDB).
Is Chloroacetyl chloride a carcinogen?
CLP Annex VI records no harmonised carcinogenicity classification for Chloroacetyl chloride. Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health.
What is the exposure limit for Chloroacetyl chloride?
The US occupational exposure limit reported for Chloroacetyl chloride is none See Appendix G (The National Institute for Occupational Safety and Health (NIOSH)). Limits differ by country: the EU sets its own indicative and binding values, and the figure that applies at a given workplace is the one in the local regulation.
What is the boiling point of Chloroacetyl chloride?
The boiling point reported for Chloroacetyl chloride is 106 °C (222.8 °F) (HSDB).
What is the melting point of Chloroacetyl chloride?
The melting point reported for Chloroacetyl chloride is -21.7 °C (-7.1 °F) (HSDB).
How should Chloroacetyl chloride be stored?
Store under nitrogen. Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Keep away from water. Never allow product to get in contact with water during storage. Hydrolyzes readily. (Hazardous Substances Data Bank (HSDB))
Nearby
Substances next to Chloroacetyl chloride
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