Substance profile
Phosphorus trichloride
Phosphorus trichloride is clear colorless, fuming liquid with a pungent odor.
01 · Identification
What Phosphorus trichloride is
Phosphorus trichloride is clear colorless, fuming liquid with a pungent odor. Its molecular formula is Cl3P and its molecular weight is 137.33 g/mol. It boils at 76.1 °C, melts at -93.6 °C, is soluble in water.
Under the GHS it carries the signal word Danger. It is classed as corrosives.
02 · Identifiers
Phosphorus trichloride identifiers and molecular data
Phosphorus trichloride CAS number and EC number
Phosphorus trichloride molecular formula and molecular weight
03 · GHS classification
Phosphorus trichloride hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
Phosphorus trichloride pictograms and signal word
Phosphorus trichloride hazard class and category
| Hazard class | Category | From code | Pictogram |
|---|---|---|---|
| Acute toxicity - oral GHS chapter 3.1 | Category 1 or 2 | H300 | GHS06 |
| Acute toxicity - inhalation GHS chapter 3.1 | Category 1 or 2 | H330 | 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 2 | H373 | GHS08 |
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.
Phosphorus trichloride hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H330 | Fatal if inhaled. |
| H300 | Fatal if swallowed. |
| H373 | May cause 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. |
Phosphorus trichloride 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 Phosphorus trichloride. 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 Phosphorus trichloride
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 Phosphorus trichloride 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
Phosphorus trichloride precautionary statements
CLP Annex VI assigns 10 precautionary statements to Phosphorus trichloride. 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.
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
Phosphorus trichloride 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 | фосфорен трихлорид |
| Spanish español | Tricloruro de fósforo |
| Czech čeština | chlorid fosforitý |
| Danish dansk | phosphortrichlorid |
| German Deutsch | Phosphortrichlorid |
| Estonian eesti | fosfortrikloriid |
| Greek ελληνικά | τριχλωριούχος φωσφόρος |
| English English | phosphorus trichloride |
| French français | trichlorure de phosphore |
| Croatian hrvatski | fosforov triklorid |
| Italian italiano | tricloruro di fosforo |
| Latvian latviešu | fosfora trihlorīds |
| Lithuanian lietuvių | fosforo trichloridas |
| Hungarian magyar | foszfor-triklorid |
| Maltese Malti | triklorur tal-fosforu |
| Dutch Nederlands | fosfortrichloride |
| Polish polski | trichlorek fosforu |
| Portuguese português | tricloreto de fósforo |
| Romanian română | triclorură de fosfor |
| Slovak slovenčina | chlorid fosforitý |
| Slovenian slovenščina | fosforjev triklorid |
| Finnish suomi | fosforitrikloridi |
| Swedish svenska | fosfortriklorid |
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
Phosphorus trichloride GHS label elements
Everything CLP Annex VI fixes for Phosphorus trichloride, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
Phosphorus trichloride
- Fatal if inhaled.
- Fatal if swallowed.
- May cause 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.
- 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.
- Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/…
- IF SWALLOWED:
- IF INHALED:
- Immediately call a POISON CENTER/doctor/…
- Get medical advice/attention if you feel unwell.
- Rinse mouth.
- Do NOT induce vomiting.
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open Phosphorus trichloride in the GHS label constructor →
07 · Health hazards
Phosphorus trichloride health hazards and exposure limits
Phosphorus trichloride hazard summary
Liquid causes second or third degree burns after short contact; [CHRIS] Highly corrosive to skin; [Quick CPC] Rats develop nephrosis and pulmonary edema after 4 hour exposures in the range of 100 ppm; 23 workers exposed to 1.8 to 27 ppm complained of eye and throat irritation; mild bronchitis was common and irritant asthma developed in some of the workers; [ACGIH] Toxic to the liver in a chronic study of animals; [Desai, H. Phosphorus and Phosphorus Compounds. In: Sullivan J, Krieger G (eds).Hazardous Materials Toxicology.Baltimore:Williams & Wilkins,1992;939] A corrosive substance that can cause pulmonary edema; [ICSC] A lachrymator; [CHEMINFO]
Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
Phosphorus trichloride occupational exposure limits
| Limit | Value | Source |
|---|---|---|
| PEL | 0.5 [ppm] | Haz-Map, Information on Hazardous Chemicals and Occupational Diseases |
| PEL | 0.5 ppm (3 mg/m³) | Occupational Safety and Health Administration (OSHA) |
| PEL | TWA 0.5 ppm (3 mg/m3) See Appendix G | The National Institute for Occupational Safety and Health (NIOSH) |
| REL | 0.2 ppm (1.5 mg/m³) | Occupational Safety and Health Administration (OSHA) |
| REL | 0.5 ppm (3 mg/m³) | Occupational Safety and Health Administration (OSHA) |
| REL | TWA 0.2 ppm (1.5 mg/m3) ST 0.5 ppm (3 mg/m3) | The National Institute for Occupational Safety and Health (NIOSH) |
| IDLH | 25 ppm (NIOSH, 2024) | CAMEO Chemicals |
| IDLH | 25.0 [ppm] | Haz-Map, Information on Hazardous Chemicals and Occupational Diseases |
| IDLH | 25 ppm | Hazardous Substances Data Bank (HSDB) |
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
Phosphorus trichloride 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.
Phosphorus trichloride boiling point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 76.1 °C (169 °F) | HSDB | |
| 76.11 °C (169 °F) | NIOSH | ||
| 76.11 °C (169 °F) | at 760 mmHg | CAMEO |
Phosphorus trichloride melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | -93.6 °C (-136.5 °F) | HSDB | |
| -112.22 °C (-170 °F) | NIOSH |
Phosphorus trichloride density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 1.58 g/cm³ | NIOSH | |
| 1.574 g/cm³ | at 21 °C | HSDB |
Phosphorus trichloride solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | Reacts with water, ethanol; soluble in benzene, chloroform, ether | HSDB | |
| Soluble in carbon tetrachloride | HSDB | ||
| Reacts | NIOSH |
Phosphorus trichloride vapor pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor pressure | 100 mmHg | NIOSH | |
| 100 mmHg | at 21 °C | CAMEO | |
| 120 mmHg | at 25 °C | HSDB |
Phosphorus trichloride autoignition temperature
| Property | Value | Conditions | Source |
|---|---|---|---|
| Autoignition temperature | Not flammable (USCG, 1999) | CAMEO |
Phosphorus trichloride lower explosive limit (LEL)
| Property | Value | Conditions | Source |
|---|---|---|---|
| Lower explosive limit (LEL) | Noncombustible Liquid; however, a strong oxidizer that may ignite combustibles upon contact. | NIOSH | |
| Reacts violently with water producing heat and decomposition products including hydrochloric acid and phosphorous acid, causing fire and explosion hazard. | decomposes | HSDB |
Phosphorus trichloride vapor density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor density | 4.75 (air = 1) | HSDB |
Phosphorus trichloride odor threshold
| Property | Value | Conditions | Source |
|---|---|---|---|
| Odor threshold | Phosphorus trichloride ... can be detected at about 0.5 mg/cu m. | HSDB |
Phosphorus trichloride critical temperature and pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Critical temperature and pressure | 285.5 °C (545.9 °F) | HSDB |
Phosphorus trichloride corrosivity
| Property | Value | Conditions | Source |
|---|---|---|---|
| Corrosivity | Corrodes most common construction materials. | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Fire and explosion
Phosphorus trichloride 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.
Phosphorus trichloride fire potential
Reacts with water to form hydrochloric acid, which reacts with most metals to form flammable hydrogen gas.
Source: Hazardous Substances Data Bank (HSDB)
10 · Handling and storage
Phosphorus trichloride storage and handling
Phosphorus trichloride safe storage
Provision to contain effluent from fire extinguishing. Separated from food and feedstuffs. See Chemical Dangers. Dry. Well closed. Ventilation along the floor.
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Phosphorus trichloride storage conditions
Provision to contain effluent from fire extinguishing. Separated from food and feedstuffs. See Chemical Dangers. Dry. Well closed. Ventilation along the floor.
Source: Hazardous Substances Data Bank (HSDB)
Phosphorus trichloride incompatible materials
Reacts with water to form hydrochloric acid, which reacts with most metals to form flammable hydrogen gas.
Source: Hazardous Substances Data Bank (HSDB)
Planning storage for a mix of chemicals? Check Phosphorus trichloride in the storage compatibility matrix →
11 · Transport
Phosphorus trichloride 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.
Phosphorus trichloride under UN 1809 — shipping name, class and packing group
Europe · ADR 2025, Table A
| Proper shipping name (3.1.2) | Class | Classification code | PG | Labels (column 5) |
|---|---|---|---|---|
| PHOSPHORUS TRICHLORIDE | 6.1 | TC3 | 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) |
|---|---|---|---|
| Phosphorus trichloride | 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
Phosphorus trichloride — frequently asked questions
What is the CAS number of Phosphorus trichloride?
The CAS number of Phosphorus trichloride is 7719-12-2. Its EC number is 231-749-3.
What is the chemical formula of Phosphorus trichloride?
The molecular formula of Phosphorus trichloride is Cl3P and its molecular weight is 137.33 g/mol.
What does a Phosphorus trichloride label have to show?
Under CLP Annex VI the label for Phosphorus trichloride carries the pictograms Skull and crossbones, Health hazard and Corrosion and the signal word is Danger.
Is Phosphorus trichloride flammable?
CLP Annex VI assigns Phosphorus trichloride 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.
Is Phosphorus trichloride a carcinogen?
CLP Annex VI records no harmonised carcinogenicity classification for Phosphorus trichloride. 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 Phosphorus trichloride?
The US occupational exposure limit reported for Phosphorus trichloride is 0.5 [ppm] (Haz-Map, Information on Hazardous Chemicals and Occupational Diseases). 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 Phosphorus trichloride?
The boiling point reported for Phosphorus trichloride is 76.1 °C (169 °F) (HSDB).
What is the melting point of Phosphorus trichloride?
The melting point reported for Phosphorus trichloride is -93.6 °C (-136.5 °F) (HSDB).
How should Phosphorus trichloride be stored?
Provision to contain effluent from fire extinguishing. Separated from food and feedstuffs. See Chemical Dangers. Dry. Well closed. Ventilation along the floor. (Hazardous Substances Data Bank (HSDB))
Nearby
Substances next to Phosphorus trichloride
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