Safety data sheet reference · CAS 7664-39-3
Hydrofluoric acid SDS
also: hydrofluoric acid MSDS · safety data sheet · HF · CAS 7664-39-3 · EC 231-634-8 · hydrogen fluoride
Official PDF from supplier
This page is a reference, not the legal document.
CAS number
7664-39-3
EC number
231-634-8
CLP Annex VI index
009-002-00-6
Molecular formula
FH
Structural formula
HF
Molar mass
20.006 g/mol
§ 02 · Hazards identification
Hydrofluoric acid harmonised EU classification
CLP Annex VI · Index 009-002-00-6. A supplier SDS may add self-classified hazards — this is the legal minimum.
Precautionary statements
Codes ending in a colon introduce the action that follows — on a label they are printed as combined statements, such as P305+P351+P338.
§ 03 · Composition and identifiers
Hydrofluoric acid molecular structure
Hydrofluoric acid is a molecular compound. The skeletal formula below is drawn from its PubChem SMILES string, and every value in this section is computed from that structure.
2D skeletal formula · HF
Hybridisation
F sp³
Electron count
8 valence e⁻ · 3 lone pairs
Identifiers from PubChem (NIH, public domain). Structure diagram drawn with RDKit from the SMILES string. Geometry and hybridisation are computed from the connection table, not measured.
§ 04 · First-aid measures
Hydrofluoric acid first aid measures
Call your national emergency number first. These are published first-aid measures, not medical advice, and they do not replace emergency services, a poison control centre or the supplier's safety data sheet.
§4–§6 below reproduce the CAMEO Chemicals entry HYDROFLUORIC ACID, SOLUTION. CAMEO publishes response data per product entry, so the entry can describe a solution, a refrigerated liquid or a molten form rather than the pure substance in §9 — check it matches what you are handling.
Refer to the ERG "General First Aid" instructions. Specific First Aid: For corrosives, in case of contact, immediately flush skin or eyes with running water for at least 30 minutes. Additional flushing may be required. In case of skin contact with Hydrofluoric acid (UN1790), if calcium gluconate gel is available, rinse 5 minutes, then apply gel. Otherwise, continue rinsing until medical treatment is available.
Source: ERG, 2024 — via CAMEO Chemicals (NOAA), public domain.
§ 05 · Fire-fighting measures
Hydrofluoric acid fire fighting measures
ERG 2024 · GUIDE 157 Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)ERG guidance is written per response guide, not per substance — Guide 157 covers every material assigned to it, so a few sentences reference other UN numbers in the same group.
Fire and explosion hazard
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. UN1802, UN2032, UN3084, UN3093, UN1796 (above 50%), UN1826 (above 50%), and UN2031 (above 65%) may act as oxidizers. Also consult ERG Guide 140. Vapors may accumulate in confined areas (basement, tanks, hopper/tank cars, etc.). Substance may react with water (some violently), releasing corrosive and/or toxic gases and runoff. Corrosives in contact with metals may evolve flammable hydrogen gas. Containers may explode when heated or if contaminated with water.
Extinguishing media and tactics
Note: Some foams will react with the material and release corrosive/toxic gases.
SMALL FIRECO2 (except for Cyanides), dry chemical, dry sand, alcohol-resistant foam.
LARGE FIREWater 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 TANKSFight 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.
Source: ERG, 2024 — via CAMEO Chemicals (NOAA), public domain. Entry: HYDROFLUORIC ACID, SOLUTION.
§ 06 · Accidental release measures
Hydrofluoric acid spill and leak response
Containment and clean-up
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 SPILLCover 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.
Initial isolation and evacuation
IMMEDIATE PRECAUTIONARY MEASUREIsolate 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.
SPILLIncrease the immediate precautionary measure distance, in the downwind direction, as necessary.
FIREIf 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.
Source: ERG, 2024 — via CAMEO Chemicals (NOAA), public domain. Entry: HYDROFLUORIC ACID, SOLUTION.
§ 07 · Handling and storage
Hydrofluoric acid computed storage compatibility
Derived from CLP Annex VI classification and CAMEO reactive-group data — not copied from a PDF.
⚠ Air-Reactive⚠ Water-Reactive
⛔ Never store with
↔ Keep separate
Full interactive verdict — reactions, gas release on contact, ADR forms →
§ 08 · Exposure controls
Hydrofluoric acid exposure limits (IDLH)
IDLH
Immediately Dangerous to Life or Health
30 ppm
Published for another entry
NIOSH published this value for Hydrogen fluoride, not for hydrofluoric acid under its own name.
NIOSH Pocket Guide — Hydrofluoric acid →
IDLH from the NIOSH Pocket Guide to Chemical Hazards (CDC, U.S. public domain), via CAMEO Chemicals. Occupational exposure limits — OSHA PEL, NIOSH REL and EU IOELV — are not published on this page yet.
§ 09 · Physical and chemical properties
Hydrofluoric acid physical properties
The full physical-property table (melting/boiling point, flash point, explosion limits, vapour pressure, density) is being populated for this substance from ECHA registration data and will appear here as it lands.
§ 10 · Stability and reactivity
Reactive group (CAMEO/NOAA): Acids, Weak, Fluoride Salts, Soluble, Water and Aqueous Solutions. Our database documents 48 incompatible and 65 caution reaction-partner groups for hydrofluoric acid — including which combinations release gas on contact. See the per-partner breakdown with gas release →
48
Incompatible
65
Caution
§ 13 · Disposal considerations
Dispose of waste and residues in accordance with local and national regulations — in the EU under the Waste Framework Directive 2008/98/EC. Never discharge to drains or municipal waste; hand contaminated packaging and unused product to an authorised waste-disposal company. The supplier's SDS section 13 lists the applicable waste codes for the specific product.
§ 14 · Transport information
Hydrofluoric acid road transport — ADR 2025
UN number
Proper shipping name
HYDROGEN FLUORIDE, ANHYDROUS
Class · PG
8 · I
Classification code
CT1
Transport category
1
ADR labels
8, 6.1
Hazard ID (Kemler) / UN plate
Top: hazard identification number (Kemler). Bottom: UN number — as carried on the orange plate of the transport unit.
Source: UN ADR 2025 (ECE/TRANS/352), Table A. Road (ADR) only — for sea (IMDG) and air (IATA), consult the supplier's SDS §14.
MSDS vs SDS
Hydrofluoric acid MSDS vs SDS: is there a difference?
MSDS (Material Safety Data Sheet) is the older name for the same document. In the US, OSHA's Hazard Communication Standard (2012) adopted the GHS-standardised 16-section Safety Data Sheet; in the EU the format is set by REACH Annex II. So a "hydrofluoric acid MSDS" and a "hydrofluoric acid SDS" refer to the same document — today it is issued as an SDS. Full breakdown of the differences →
Other mineral acids in our database
Substance profile
What hydrofluoric acid is
Physical and chemical properties with the conditions each value was measured under, synonyms, formula and the harmonised CLP classification →
Compliance hub
From classification to SDS
The classification above corresponds to Section 2 of a Safety Data Sheet. Learn how a compliant 16-section SDS is structured and authored →
GHS label maker
Build the label for hydrofluoric acid
Pictograms, signal word and H-statements combined into a compliant label layout →
§ 16 · Sources
- Classification: Regulation (EC) No 1272/2008 (CLP), Annex VI
- Transport: UN ADR 2025 (UNECE), Table A
- Reactivity: NOAA CAMEO Chemicals reactive-group matrix (public domain)
- Physical properties: CAMEO Chemicals (NOAA, public domain) — per-value source references stored in the database
- Emergency response (§4–§6): ERG 2024 (PHMSA) · NIOSH Pocket Guide (CDC) · CHRIS (USCG) · NTP · EPA — via CAMEO Chemicals (NOAA), all US federal public domain, reproduced verbatim
- Substance data: PubChem · ECHA
Reference aid only. This page summarises the harmonised EU classification and computed storage guidance — it is not a Safety Data Sheet and does not replace one. Always verify hazards, handling and storage against the supplier's SDS (sections 7 and 10) and local regulations before use. Page updated 2026-08-11.
Frequently asked questions about hydrofluoric acid
Is an MSDS the same as an SDS?
In practice, yes. MSDS (Material Safety Data Sheet) is the older name for the same document. In the US, OSHA's Hazard Communication Standard (2012) adopted the GHS-standardised 16-section Safety Data Sheet; in the EU the SDS format is set by REACH Annex II. A document you find labelled "hydrofluoric acid MSDS" is today issued as an SDS.
What GHS pictograms does hydrofluoric acid require?
Under the harmonised EU classification (CLP Annex VI), hydrofluoric acid carries GHS05 and GHS06 with the signal word "Danger". Hazard statements: H310, H330, H300, H314. A supplier's SDS may add self-classified hazards on top of this harmonised minimum.
What should hydrofluoric acid never be stored with?
Based on its storage classes (Mineral acids, Acute toxics), hydrofluoric acid must not share storage with: Bases; Cyanides & sulfides; Organic peroxides & self-reactives; Oxidizing acids; Oxidizers; Reactive metals; Water-reactives. Verify against the supplier's SDS sections 7 and 10 before finalising storage.
Where can I download an official hydrofluoric acid SDS PDF?
From your own supplier — an SDS is issued per product and supplier, so the correct PDF for an inspection is the one matching the product you actually purchased. The supplier links on this page lead to the official SDS libraries of major distributors.
Call emergency services first
112 in the EU · 911 in the US. This screen is published response information, not medical advice, and it does not replace emergency services, a poison centre or the supplier's safety data sheet.
Text below is the CAMEO Chemicals entry HYDROFLUORIC ACID, SOLUTION — confirm it matches the form in front of you.
01 · First aid
What to do for the person
Refer to the "General First Aid" section. Specific First Aid: For corrosives, in case of contact, immediately flush skin or eyes with running water for at least 30 minutes. Additional flushing may be required. In case of skin contact with Hydrofluoric acid (UN1790), if calcium gluconate gel is available, rinse 5 minutes, then apply gel. Otherwise, continue rinsing until medical treatment is available.
02 · Fire
Extinguishing and tactics
Fire and explosion hazard
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. UN1802, UN2032, UN3084, UN3093, UN1796 (above 50%), UN1826 (above 50%), and UN2031 (above 65%) may act as oxidizers. Also consult ERG Guide 140. Vapors may accumulate in confined areas (basement, tanks, hopper/tank cars, etc.). Substance may react with water (some violently), releasing corrosive and/or toxic gases and runoff. Corrosives in contact with metals may evolve flammable hydrogen gas. Containers may explode when heated or if contaminated with water.
Extinguishing media and tactics
Note: Some foams will react with the material and release corrosive/toxic gases.
SMALL FIRECO2 (except for Cyanides), dry chemical, dry sand, alcohol-resistant foam.
LARGE FIREWater 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 TANKSFight 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.
03 · Spill
Containment, isolation, evacuation
Containment and clean-up
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 SPILLCover 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.
Initial isolation and evacuation
IMMEDIATE PRECAUTIONARY MEASUREIsolate 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.
SPILLIncrease the immediate precautionary measure distance, in the downwind direction, as necessary.
FIREIf 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.
Sources: ERG 2024 (PHMSA) · NIOSH Pocket Guide (CDC) · CHRIS (USCG) · NTP · EPA — via CAMEO Chemicals (NOAA), public domain. Text reproduced verbatim.