R32 Difluoromethane Refrigerant · Safety Data Sheet (SDS)

1.1 Product identifier

1.2 Details of the supplier of the safety data sheet

1.3 Emergency telephone number

National Chemical Emergency Hotline (China): +86-532-83889090 (24 hours)

Supplier Emergency Contact: +86 551 6558 9290

2.1 GHS classification

2.2 GHS label elements

Signal word: Warning

2.3 Other hazards

• Vapor is heavier than air (vapor density ~1.8, air = 1) and may spread long distances along the ground; may flash back to ignition source.
• Decomposes at high temperatures (>250°C) producing toxic and corrosive gases (hydrogen fluoride, carbon monoxide, carbonyl fluoride, etc.).
• Cylinders may rupture or burst when heated due to increased internal pressure.
• A2L mildly flammable gas: very low burning velocity, relatively high ignition energy, but still presents a fire/explosion risk in confined or oxygen-enriched environments.

3.1 Substance/mixture

This product is a pure substance.

3.2 Composition information

3.3 Impurity information

4.1 Description of necessary first aid measures

General advice: Remove victim from contaminated area immediately. Keep warm and at rest. Show this SDS to attending physician.

Inhalation:

• Move victim to fresh air immediately. Keep airway clear.
• Administer oxygen if breathing is difficult.
• If not breathing, give artificial respiration (preferably with bag-valve-mask or pocket mask; avoid mouth-to-mouth).
• If no pulse, start cardiopulmonary resuscitation (CPR) immediately.
• Keep victim warm and at rest. Monitor condition closely.
• Seek medical attention immediately.

Skin contact (frostbite):

• Immediately flush affected area with large amounts of lukewarm water (37–40°C) to promote rewarming.
• Do NOT use hot water (>40°C) or direct heat (e.g., electric heaters).
• Do NOT rub or massage frostbitten area; this may worsen tissue damage.
• Carefully remove frozen clothing. If clothing sticks to skin, do NOT pull it off; cut around it.
• Cover with sterile dressing.
• Seek medical attention immediately.

Eye contact:

• Immediately hold eyelids open and rinse thoroughly with plenty of water or normal saline for at least 15 minutes.
• Ensure complete irrigation of all eye surfaces by lifting upper and lower lids.
• Remove contact lenses if present and easily removable.
• Seek medical attention immediately, preferably from an ophthalmologist.

Ingestion:

Not applicable. This substance is a gas at ambient temperature; ingestion exposure is not expected.

4.2 Most important symptoms and effects, both acute and delayed

• Acute inhalation: dizziness, drowsiness, headache, nausea, ataxia, loss of consciousness, cardiac arrhythmia.
• Skin contact (liquid): frostbite (pale, hard skin, pain, blistering).
• Eye contact (liquid): severe frostbite, corneal damage, visual impairment.
• Combustion exposure: if combustion occurs, inhalation of thermal decomposition products (HF, etc.) can cause severe respiratory burns and pulmonary edema.

4.3 Indication of any immediate medical attention and special treatment needed

5.1 Extinguishing media

Suitable extinguishing media: Use extinguishing agent appropriate for surrounding fire. Dry chemical, carbon dioxide, water fog, and foam are acceptable.

Unsuitable extinguishing media: Direct strong water jet onto leaking liquefied gas (accelerates evaporation and dispersion).

5.2 Special hazards arising from the substance or mixture

• R32 is a flammable gas; flammability limits 14.4%–29.3% (vol in air).
• Vapor is heavier than air and may accumulate in low-lying areas; flash back to ignition source.
• Thermal decomposition at high temperatures (>250°C) produces toxic and corrosive gases: hydrogen fluoride, carbon monoxide, carbonyl fluoride, etc.
• Cylinders may rupture or burst when heated. If a leaking gas fire cannot be stopped at the source, do not extinguish.

5.3 Hazardous combustion products

Hydrogen fluoride (HF), carbon monoxide (CO), carbonyl fluoride (COF₂), and other fluorinated compounds.

5.4 Advice for firefighters

• Firefighters must wear positive-pressure self-contained breathing apparatus (SCBA) and full protective fire-resistant clothing.
• If the leaking gas source is already on fire and cannot be shut off, DO NOT extinguish — let the gas continue to burn while cooling surrounding containers ("do not extinguish if source cannot be shut off" principle).
• If the source can be safely shut off, shut off then extinguish.
• If possible, move containers from fire area to a safe location.
• Cool containers with water spray from a safe distance until fire is extinguished.
• Immediately evacuate if containers show discoloration or if pressure relief devices begin to vent.
• Isolate the area; keep unauthorized personnel out; eliminate all ignition sources.

6.1 Personal precautions, protective equipment and emergency procedures

• Evacuate personnel from the leak area to upwind locations immediately. Establish a perimeter and restrict access.
• Eliminate all ignition sources (open flame, sparks, static electricity); prohibit use of spark-generating equipment and tools.
• Emergency responders should wear SCBA, anti-static flame-retardant clothing, cryogenic gloves, and eye protection.
• Enter from upwind direction.
• Stop leak if it can be done safely.
• Do not touch or walk through spilled material.
• Maintain emergency contact personnel for external support.

6.2 Environmental precautions

• Prevent gas from entering sewers, basements, or confined spaces (flammable gas accumulation poses explosion risk).
• Ventilate the area to accelerate dispersion.
• Minimize releases to control greenhouse gas emissions; recover whenever possible.
• Avoid release to atmosphere, waterways, or soil.

6.3 Methods and materials for containment and cleaning up

• Small leak: Increase ventilation to accelerate gas dispersion. Monitor flammable gas concentration and oxygen levels to prevent fire and asphyxiation.
• Large leak:
  • Close source valve if safe to do so; eliminate nearby ignition sources.
  • Recover using dedicated gas recovery equipment.
  • If recovery is not possible, use water fog/mist to dilute (prevent water pollution).
  • If cylinder valve cannot be closed, move cylinder to a safe ventilated area and vent slowly.
• Cylinder leak: Move cylinder to a well-ventilated safe area and vent slowly. If valve cannot be closed, contact supplier for professional handling.

6.4 Reference

See Section 8 (Exposure controls/personal protection) and Section 13 (Disposal considerations).

7.1 Precautions for safe handling

• Handle in closed systems with adequate natural ventilation or local exhaust.
• Personnel must be specially trained and strictly follow operating procedures. Certified personnel only.
• Prevent gas leakage into workplace atmosphere.
• Flammable gas management: Keep away from fire, heat sources; no smoking in work areas; use explosion-proof ventilation systems and equipment; avoid static buildup, ensure equipment and piping are reliably grounded.
• Avoid contact with reactive metals and strong oxidizing agents.
• Handle cylinders carefully; do not drop, slide, roll, or bump cylinders. Use proper lifting equipment.
• Equip area with leak emergency response equipment.
• Wear insulated gloves and eye/face protection when handling liquid to prevent frostbite.
• Periodically inspect cylinders, valves, and piping for leaks.

7.2 Conditions for safe storage, including any incompatibilities

• Store in a cool, dry, well-ventilated flammable gas warehouse; store separately from oxidizing gases and oxidizers.
• Storage temperature should not exceed 30°C. Keep away from fire, heat sources, and direct sunlight.
• Store separately from oxidizers, reactive metals, halogens, etc. Do not co-store with incompatible materials.
• Storage area should be equipped with leak emergency response equipment and appropriate fire extinguishing equipment.
• Cylinders must be stored upright with valve caps and safety rings in place, properly secured to prevent falling.
• Use explosion-proof lighting and ventilation systems.
• Prohibit use of equipment and tools that can generate sparks.
• Storage area should be equipped with flammable gas detection alarms and clear safety warning signs.
• Implement two-person receiving/issuing and two-person custody system.

7.3 Specific end uses

For industrial use only. Primarily used in refrigeration systems (alone or as a blend component). Personnel must be professionally trained. Do not use for direct food contact, medical inhalation, or other unapproved applications. Systems using R32 must account for its mild flammability and incorporate appropriate explosion-proof and leak detection measures.

8.1 Control parameters

Note: Per GBZ 2.1-2019, this substance is not currently listed in the Chinese OEL table. International standards are recommended as reference.

8.2 Exposure monitoring methods

Gas chromatography with flame ionization detection (GC-FID) or mass spectrometry (GC-MS); combustible gas detectors (infrared or catalytic combustion type) for workplace flammable gas concentration monitoring.

8.3 Appropriate engineering controls

• Enclosed process design with general ventilation or local exhaust.
• Provide safety shower and eyewash station.
• Install flammable gas detection alarms in areas where leaks may occur, interlocked with ventilation systems.
• Use explosion-proof electrical equipment; all equipment and piping must be reliably grounded for static electricity protection.

8.4 Individual protection measures

Respiratory protection:

• Normal conditions (below exposure limit): no special protection required.
• Elevated concentrations: half-face respirator with organic vapor cartridge is recommended.
• High concentration or emergency rescue/evacuation: positive-pressure self-contained breathing apparatus (SCBA) must be worn.

Eye/face protection:

• General handling: chemical safety goggles.
• When handling liquid or potential liquid exposure: goggles/face shield must be worn to prevent frostbite.

Skin protection:

• Hand protection: anti-static gloves for normal handling; cryogenic-insulated gloves (e.g., dry ice gloves, leather cold gloves) for liquid contact.
• Body protection: anti-static flame-retardant work clothing; cold-resistant clothing for liquid contact.
• Other: no smoking in work areas; avoid high-concentration inhalation; use a buddy system when entering tanks, confined spaces, or other high-concentration areas; use explosion-proof tools.

8.5 Hygiene measures

• Remove contaminated clothing and wash skin thoroughly after work.
• Maintain good personal hygiene.
• Ensure eyewash and emergency shower are available in the workplace.

9.1 Basic physical and chemical properties

9.2 Thermodynamic properties

9.3 Other safety data

10.1 Reactivity

Chemically stable under normal temperature and pressure conditions; not readily reactive. However, it has a flammable range in air (14.4%–29.3%) and can burn with an ignition source.

10.2 Chemical stability

Stable under normal conditions of temperature and pressure. Within the flammable concentration range, it can burn with an ignition source (A2L mildly flammable; very low burning velocity).

10.3 Possibility of hazardous reactions

• In air (14.4%–29.3% by volume), can burn with an ignition source (open flame, high heat, electric spark). Burning velocity is very low and ignition energy is relatively high.
• Thermal decomposition at high temperatures (>250°C) produces toxic hydrogen fluoride, carbon monoxide, and carbonyl fluoride.
• May react with alkali metals, alkaline earth metals, and aluminum powder under high temperature or specific conditions.
• May undergo oxidation-reduction reactions with strong oxidizing agents.

10.4 Conditions to avoid

High temperature, open flame, ignition sources (electric sparks, static electricity), direct heat sources, cylinder overpressure

10.5 Incompatible materials

Reactive metals (sodium, potassium, calcium, aluminum powder, magnesium powder, etc.), strong oxidizing agents, halogens

10.6 Hazardous decomposition products

Hydrogen fluoride (HF), carbon monoxide (CO), carbonyl fluoride (COF₂), and other fluorinated compounds

10.7 Hazardous polymerization

Will not occur.

11.1 Information on toxicological effects

Acute toxicity:

11.2 Skin irritation/corrosion

Liquid contact can cause frostbite (physical injury), but is not a chemical corrosive. GHS classification: no skin corrosion/irritation classification (physical frostbite only).

11.3 Eye irritation/corrosion

Liquid contact can cause severe frostbite and corneal damage. Based on physical cryogenic injury effect.

11.4 Respiratory or skin sensitization

No sensitization reported. Available animal test data and human epidemiology data show no sensitization effect.

11.5 Germ cell mutagenicity

In vitro and in vivo tests (Ames test, chromosome aberration test, mouse micronucleus test, etc.) show no mutagenic effect.

11.6 Carcinogenicity

Insufficient evidence for carcinogenicity.

• IARC (International Agency for Research on Cancer): Not listed
• ACGIH (American Conference of Governmental Industrial Hygienists): Category A4 (Not classifiable as a human carcinogen)

11.7 Reproductive toxicity

Animal studies show no significant reproductive or developmental toxicity at high concentrations. No human reproductive toxicity data available.

11.8 STOT-single exposure

• Narcotic effect (Category 3): Inhalation of high concentrations may cause central nervous system depression, manifested as dizziness, drowsiness, headache, and impaired consciousness.
• Cardiac effects: High-concentration exposure may cause cardiac arrhythmia, especially under stress or exercise (catecholamine sensitization).

11.9 STOT-repeated exposure

Repeated low-concentration exposure shows no significant target organ toxicity. Long-term animal inhalation studies (high concentrations) have not shown clear organ damage.

11.10 Aspiration hazard

Not expected to cause aspiration pneumonia in gaseous form. However, high-concentration inhalation can cause CNS depression and cardiac sensitization. If combustion occurs, inhalation of thermal decomposition products (HF) can cause severe respiratory burns and pulmonary edema.

12.1 Ecotoxicity

12.2 Persistence and degradability

• Atmospheric degradation: Primarily degraded by reaction with hydroxyl radicals; atmospheric lifetime ~5.2 years.
• Biodegradability: Poorly biodegradable (not readily degraded by microorganisms).
• Hydrolysis: Not readily hydrolyzed at ambient temperature.
• Photodegradation: Can be photochemically degraded in the atmosphere.

12.3 Bioaccumulative potential

log P = 0.21. Low bioaccumulation potential (below the bioconcentration threshold of log P = 4.5).

12.4 Mobility in soil

Highly volatile in gaseous form. Low water solubility. High mobility. Volatilizes readily to atmosphere when released to soil.

12.5 Results of PBT and vPvB assessment

Does not meet PBT (persistent, bioaccumulative, and toxic) / vPvB (very persistent and very bioaccumulative) criteria.

12.6 Other adverse effects

• Ozone Depletion Potential (ODP): 0 (does not deplete the ozone layer; HFC-class non-ODS substance)
• Global Warming Potential (GWP, 100-year time horizon): ~677 (relative to CO₂ = 1)
• Large releases contribute to global warming; emissions should be controlled with priority on recovery and reuse. R32 has a relatively low GWP among HFC refrigerants and is regarded as a more environmentally friendly transitional refrigerant.
• Not a controlled substance under the Montreal Protocol, but is a greenhouse gas listed under the Kyoto Protocol and Paris Agreement. Under the Kigali Amendment to the Montreal Protocol, HFC substances are being phased down.

13.1 Waste treatment methods

Product/residues:

• Do NOT release directly to atmosphere (greenhouse gas and flammable gas).
• Recovery and recycling (purification and reuse) is the preferred approach.
• If recovery is not feasible, dispose of through a licensed hazardous waste treatment facility.
• High-temperature incineration with alkaline scrubber for fluoride removal is an acceptable method. Incineration must ensure complete combustion and address flammable gas risks.
• Do not discharge to sewers, waterways, or soil.

Contaminated packaging:

• Empty cylinders must be returned to supplier or a qualified facility for disposal. Do not discard or cut empty cylinders.
• Empty cylinders with residual pressure are managed as hazardous waste. Residual flammable gas must be safely vented under ventilation before disposal.

13.2 Special precautions for disposal

• Refer to national and local regulations before disposal (e.g., Solid Waste Pollution Prevention and Control Law, Hazardous Waste Storage Pollution Control Standards, etc.).
• Personnel should wear appropriate personal protective equipment (see Section 8).
• Ensure good ventilation to prevent asphyxiation and flammable gas accumulation. No ignition sources at the disposal site.
• Disposal must be performed by a qualified and licensed facility.
• Disposal records should be maintained.

14.1 UN number

3252 (Difluoromethane, flammable liquefied gas)

14.2 UN proper shipping name

DIFLUOROMETHANE

14.3 Transport hazard class(es)

Class 2.1 Flammable gas

14.4 Packing group

Not applicable (Class 2 gases are not assigned a packing group)

14.5 Packing mark / Hazard label

• Primary hazard label: Flammable gas (red, Class 2.1)
• Subsidiary hazard label: None

14.6 Methods and materials for containment and packaging

• Seamless steel cylinders. Cylinders must comply with applicable national standards (e.g., GB 5099).
• Common package sizes: 13.6 kg, 50 kg, 100 kg, 400 kg, 800 kg cylinders, and ISO tank containers.
• Cylinder valve outlet thread direction: left-hand thread for flammable gases.

14.7 Special requirements for different modes of transport

Road transport (GB/T 12268 / ADR):

• Vehicles must have hazardous cargo transport license and be fitted with spark arrestors.
• Cylinders must have valve caps and safety rings in place.
• Cylinders generally laid flat with valves pointing in same direction; do not stack crosswise. Height must not exceed vehicle guardrail.
• Transport during early morning/evening in summer to avoid direct sunlight.
• Follow designated routes; do not stop in residential or densely populated areas.
• Vehicle must be equipped with fire extinguishing equipment and leak emergency response gear.

Rail transport (RID):

• Prohibit hump shunting (no free-roll classification).
• Transport in boxcars; cylinders upright or laid flat and secured.

Marine transport (IMDG Code):

• UN 3252, Class 2.1
• Marine pollutant: No
• Stowage category: D (on deck only)
• Keep away from heat sources; isolate from ignition sources

Air transport (ICAO/IATA DGR):

• UN 3252, Class 2.1
• Flammable liquefied gas
• Forbidden on passenger aircraft (cargo aircraft only, subject to quantity limits)

14.8 Special precautions for user

• Do not co-transport with oxidizers, reactive metals, halogens, or food/feed products.
• Vehicles must be equipped with appropriate fire extinguishing equipment and leak emergency response gear.
• Transport personnel must be specially trained and certified.
• Protect from sunlight, rain, and high temperature during transit.
• When stopping en route, stay away from fire, heat sources, and high-temperature areas.
• Exhaust pipes of vehicles carrying this product must be fitted with spark arrestors.
• Load and unload carefully to prevent damage to cylinders and fittings; use explosion-proof tools and prevent static buildup.

15.1 Safety, health and environmental regulations/legislation specific for the substance or mixture

Chinese regulations:

• Regulation on the Safety Management of Hazardous Chemicals (State Council Decree No. 591)
• Catalog of Hazardous Chemicals (2015 edition): listed
• GB 30000 series (Rules for classification and labelling of chemicals)
• GB/T 16483-2008 (Content and order of sections in safety data sheet for chemical products)
• Regulation on Safe Use of Chemicals in the Workplace (Labor Ministry, 1996)
• GBZ 2.1-2019 (Occupational exposure limits for hazardous agents in the workplace — Part 1: Chemical agents)
• TSG 23-2021 (Safety Technical Regulation for Gas Cylinders)
• Regulations on Road Transport of Dangerous Goods
• Law of the People's Republic of China on Work Safety
• Law of the People's Republic of China on the Prevention and Control of Atmospheric Pollution (incl. greenhouse gas control)
• Law of the People's Republic of China on Prevention and Control of Environmental Pollution by Solid Waste
• Regulation on Ozone-Depleting Substances: not a controlled substance (ODP = 0)

International regulations:

• UN GHS (Globally Harmonized System of Classification and Labelling of Chemicals): 8th revised edition
• Montreal Protocol: Not a controlled ozone-depleting substance (ODP = 0)
• Kigali Amendment to the Montreal Protocol: HFC substances listed for phase-down
• Kyoto Protocol / Paris Agreement: Listed as greenhouse gas (HFC class)
• EU REACH Regulation (EC 1907/2006): Registered substance
• EU CLP Regulation (EC 1272/2008): Classification, labelling and packaging regulation
• EU F-Gas Regulation (EC 517/2014): Fluorinated greenhouse gas controls, including quota management
• US EPA SNAP Program: Approved for various refrigeration applications
• US OSHA HCS 2012: Hazard Communication Standard
• US DOT 49 CFR: Hazardous Materials Transportation Regulations
• ADR/RID: European Agreement concerning the International Carriage of Dangerous Goods by Road/Rail
• IMDG Code: International Maritime Dangerous Goods Code
• IATA DGR: International Air Transport Association Dangerous Goods Regulations

16.1 References

• NIOSH Pocket Guide to Chemical Hazards
• NOAA CAMEO Chemicals Database
• PubChem Compound Database (CID 6225)
• ASHRAE Handbook - Refrigeration Systems and Applications
• ASHRAE Standard 34 - Designation and Safety Classification of Refrigerants
• GB/T 16483-2008 (Content and order of sections in safety data sheet for chemical products)
• GB 30000 series (Rules for classification and labelling of chemicals)
• United Nations GHS (Globally Harmonized System of Classification and Labelling of Chemicals), 8th revised edition
• OSHA Hazard Communication Standard (29 CFR 1910.1200)

16.2 Abbreviations

16.3 Disclaimer

This Safety Data Sheet (SDS) has been prepared in accordance with the UN GHS standard and applicable regulatory requirements. The information contained herein is based on publicly available chemical databases, technical literature, and national standards, and is believed to be accurate and complete as of the date of issuance. However, no warranty, express or implied, is made as to the absolute accuracy, completeness, or reliability of the information. Users should verify the applicability of the information for their specific use conditions and refer to the official SDS provided by the manufacturer/supplier for compliance purposes. The information in this document may be updated as new research findings and regulatory changes become available; periodic review of the latest version is recommended.