Substance profile
Trichlorosilane
Trichlorosilane is a colorless liquid with an acrid odor.
01 · Identification
What Trichlorosilane is
Trichlorosilane is a colorless liquid with an acrid odor. It boils at 31.8 °C, melts at -126 °C.
Under the GHS it carries the signal word Danger. It is classed as corrosives.
02 · Identifiers
Trichlorosilane identifiers and molecular data
Trichlorosilane CAS number and EC number
Trichlorosilane molecular formula and molecular weight
03 · GHS classification
Trichlorosilane hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
Trichlorosilane pictograms and signal word
Trichlorosilane hazard class and category
| Hazard class | Category | From code | Pictogram |
|---|---|---|---|
| Flammable liquids GHS chapter 2.6 | Category 1 | H224 | GHS02 |
| In contact with water emits flammable gases GHS chapter 2.12 | Category 1 | H260 | GHS02 |
| Acute toxicity - oral GHS chapter 3.1 | Category 4 | H302 | GHS07 |
| 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 |
| Serious eye damage/eye irritation GHS chapter 3.3 | Category 1 | H318 | GHS05 |
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.
Trichlorosilane hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H224 | Extremely flammable liquid and vapour. |
| H260 | In contact with water releases flammable gases which may ignite spontaneously. |
| H331 | Toxic if inhaled. |
| H302 | Harmful if swallowed. |
| H314 | Causes severe skin burns and eye damage. |
| H318 | Causes serious eye damage. |
Trichlorosilane supplemental EU statements (EUH)
| Code | Statement |
|---|---|
| EUH014 | Reacts violently with water. |
| EUH029 | Contact with water liberates toxic gas. |
| EUH071 | Corrosive to the respiratory tract. |
This page lists only the codes assigned to Trichlorosilane. 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 Trichlorosilane
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 Trichlorosilane 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
Trichlorosilane precautionary statements
CLP Annex VI assigns 17 precautionary statements to Trichlorosilane. 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
Trichlorosilane 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 | трихлоросилан |
| Spanish español | Triclorosilano |
| Czech čeština | trichlorsilan |
| Danish dansk | trichlorsilan |
| German Deutsch | Trichlorsilan |
| Estonian eesti | triklorosilaan |
| Greek ελληνικά | τριχλωροσιλάνιο |
| English English | trichlorosilane |
| French français | trichlorosilane |
| Croatian hrvatski | triklorsilan |
| Italian italiano | triclorosilano |
| Latvian latviešu | trihlorsilāns |
| Lithuanian lietuvių | trichlorsilanas |
| Hungarian magyar | triklórszilán |
| Maltese Malti | triklorosilan |
| Dutch Nederlands | trichloorsilaan |
| Polish polski | trichlorosilan |
| Portuguese português | triclorossilano |
| Romanian română | triclorosilan |
| Slovak slovenčina | trichlórsilán |
| Slovenian slovenščina | triklorosilan |
| Finnish suomi | trikloorisilaani |
| Swedish svenska | triklorsilan |
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
Trichlorosilane GHS label elements
Everything CLP Annex VI fixes for Trichlorosilane, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
Trichlorosilane
- Extremely flammable liquid and vapour.
- In contact with water releases flammable gases which may ignite spontaneously.
- Toxic if inhaled.
- Harmful if swallowed.
- Causes severe skin burns and eye damage.
- Causes serious eye damage.
- Reacts violently with water.
- Contact with water liberates toxic gas.
- Corrosive to the respiratory tract.
- Keep away from heat, hot surfaces, sparks, open flames and other ignition sources. No smoking.
- Keep container tightly closed.
- Use explosion-proof [electrical/ventilating/lighting/…] equipment.
- Use only non-sparking tools.
- 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:
- IF IN EYES:
- Immediately call a POISON CENTER/doctor/…
- Call a POISON CENTER/doctor/… if you feel unwell.
- Rinse mouth.
- Do NOT induce vomiting.
- Remove contact lenses, if present and easy to do. Continue rinsing.
- Store in a well-ventilated place.
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open Trichlorosilane in the GHS label constructor →
07 · Health hazards
Trichlorosilane health hazards and exposure limits
Trichlorosilane hazard summary
Reacts with water to release HCl; Corrosive to skin and can produce pneumonitis after inhalation of high concentrations; May ignite on exposure to air; [CSH, p. 418] Highly corrosive to skin; [Quick CPC] A lachrymator; [HSDB] See the Process, Toxic Gas from Spilling Chemical in Water.
Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
08 · Physical and chemical properties
Trichlorosilane 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.
Trichlorosilane boiling point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 31.8 °C (89.2 °F) | at 760 mmHg | HSDB |
| 32.22 °C (90 °F) | at 760 mmHg | CAMEO | |
| 31.8 °C (89.2 °F) | ICSC |
Trichlorosilane melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | -126.5 °C (-195.7 °F) | HSDB | |
| -127.22 °C (-197 °F) | CAMEO |
Trichlorosilane density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 1.34 g/cm³ | ICSC | |
| 1.3417 g/cm³ | at 20 °C | HSDB | |
| 1.344 g/cm³ | at 20 °C | CAMEO |
Trichlorosilane solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | Sol in benzene, carbon disulfide, chloroform, carbon tetrachloride | HSDB | |
| Sol in ether, heptane, perchloroethylene | HSDB | ||
| Solubility in water: reaction | ICSC |
Trichlorosilane vapor pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor pressure | 493.541 mmHg | at 20 °C | ICSC |
| 750 mmHg | at 31.6 °C | DOE PAC | |
| 594 mmHg | Haz-Map |
Trichlorosilane flash point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Flash point | -13.89 °C (7 °F) | HSDB | |
| -27 °C (-16.6 °F) | ICSC | ||
| -50 °C (-58 °F) | above this value | CAMEO |
Trichlorosilane autoignition temperature
| Property | Value | Conditions | Source |
|---|---|---|---|
| Autoignition temperature | 182.22 °C (360 °F) | HSDB | |
| 104.44 °C (220 °F) | CAMEO | ||
| 185 °C (365 °F) | ICSC |
Trichlorosilane lower explosive limit (LEL)
| Property | Value | Conditions | Source |
|---|---|---|---|
| Lower explosive limit (LEL) | 1.2 % by volume | HSDB |
Trichlorosilane upper explosive limit (UEL)
| Property | Value | Conditions | Source |
|---|---|---|---|
| Upper explosive limit (UEL) | 90.5 % by volume | HSDB |
Trichlorosilane vapor density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor density | 4.67 (air = 1) | HSDB | |
| 4.7 (air = 1) | ICSC |
Trichlorosilane corrosivity
| Property | Value | Conditions | Source |
|---|---|---|---|
| Corrosivity | Corrodes metal after reacting with moisture to form hydrochloric acid | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Fire and explosion
Trichlorosilane 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.
Trichlorosilane fire potential
A very dangerous fire hazard when exposed to heat, flame, or by chemical reaction.
Source: Hazardous Substances Data Bank (HSDB)
10 · Handling and storage
Trichlorosilane storage and handling
Trichlorosilane safe storage
Fireproof. Separated from food and feedstuffs and incompatible materials. See Chemical Dangers. Cool. Dry. Well closed. Ventilation along the floor.
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Trichlorosilane storage conditions
Fireproof. Separated from food and feedstuffs and incompatible materials ... Cool. Dry. Well closed. Ventilation along the floor.
Source: Hazardous Substances Data Bank (HSDB)
Trichlorosilane incompatible materials
... Water reactive. Hydrochloric acid is released ... Reacts violently with water and aqueous soln, alcohols, organic acids, peroxides, amines, and oxidizing materials ...
Source: Hazardous Substances Data Bank (HSDB)
Trichlorosilane reactivity
TRICHLOROSILANE reacts with alcohols, acetone, light metals with generation of heat and combustible (H2) and corrosive (HCl) gases [Handling Chemicals Safely 1980. p. 924].
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Trichlorosilane in the storage compatibility matrix →
11 · Transport
Trichlorosilane 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.
Trichlorosilane under UN 1295 — shipping name, class and packing group
Europe · ADR 2025, Table A
| Proper shipping name (3.1.2) | Class | Classification code | PG | Labels (column 5) |
|---|---|---|---|---|
| TRICHLOROSILANE | 4.3 | WFC | I | |
Source: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE). Class 4.3 is “Substances which, in contact with water, emit flammable gases” (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) |
|---|---|---|---|
| Trichlorosilane | 4.3 | I | |
Source: 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03. Class 4.3 is “Dangerous when wet material” (49 CFR 173.2).
12 · Questions
Trichlorosilane — frequently asked questions
What is the CAS number of Trichlorosilane?
The CAS number of Trichlorosilane is 10025-78-2. Its EC number is 233-042-5.
What does a Trichlorosilane label have to show?
Under CLP Annex VI the label for Trichlorosilane carries the pictograms Flame, Skull and crossbones and Corrosion and the signal word is Danger.
Is Trichlorosilane flammable?
Yes. CLP Annex VI assigns Trichlorosilane H224 and H260 — extremely flammable liquid and vapour. The flash point reported for it is -13.89 °C (7 °F) (HSDB).
Is Trichlorosilane a carcinogen?
CLP Annex VI records no harmonised carcinogenicity classification for Trichlorosilane. 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 boiling point of Trichlorosilane?
The boiling point reported for Trichlorosilane is 31.8 °C (89.2 °F), at 760 mmHg (HSDB).
What is the melting point of Trichlorosilane?
The melting point reported for Trichlorosilane is -126.5 °C (-195.7 °F) (HSDB).
How should Trichlorosilane be stored?
CLP Annex VI assigns Trichlorosilane the storage statement P403. Fireproof. Separated from food and feedstuffs and incompatible materials ... Cool. Dry. Well closed. Ventilation along the floor. (Hazardous Substances Data Bank (HSDB))
Nearby
Substances next to Trichlorosilane
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