Dichlorodifluoromethane

Flammability

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

flammable gases

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

not specified

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

- Principle of test: the gas sample is mixed with air in pre-determined proportions and heated. The flammable potential is determined by observation of flame propagation after a source of ignition is introduced.
- Short description of test conditions: the gaseous sample is introduced as a gas-air mixture in a cylindrical steel vessel, heated externally by gas burners. A source of ignition is introduced at one end of the cyclinder.
- Parameters analysed / observed: flame propagation

GLP compliance:

no

Key result

Parameter:

lower explosion limit

Remarks:

No flame propagation at up to 100°C initial temperature

Remarks on result:

not determinable

Remarks:

No flammable range determined under the test conditions

Key result

Parameter:

upper explosion limit

Remarks:

No flame propagation at up to 100°C initial temperature

Remarks on result:

not determinable

Remarks:

No flammable range determined under the test conditions

Interpretation of results:

not classified based on GHS criteria

Reference 2

Endpoint:

flammable gases

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Principles of method if other than guideline:

- Principle of test: flammability testing according to ASTM standard E-681 (1985)
- Short description of test conditions: the refrigerant was tested in a spherical flask of 5 L volume at atmospheric temperature and 21°C. Ignition source: match
- Parameters analysed / observed: flame propagation criteria based on visual observation of the cone angle

GLP compliance:

no

Key result

Parameter:

lower explosion limit

Remarks:

No flame propagation observed

Remarks on result:

no flammable range with air at 20°C and 101.3 kPa

Remarks:

(tested at 21°C)

Key result

Parameter:

upper explosion limit

Remarks:

No flame propagation observed

Remarks on result:

no flammable range with air at 20°C and 101.3 kPa

Remarks:

(tested at 21°C)

Key result

Parameter:

other: Adiabatic flame temperature

Value:

1 308.2 other: Kelvin

Remarks on result:

not flammable based on calculation method

Remarks:

(1034.85 °C)

As a screening approach the flammability can be correlated to the adiabatic flame temperature. The adiabatic flame temperature for R-12 was determined to be 1308.2 K (1034.85°C). No flammability limit could be determined.

All common gaseous refrigerants known to be flammable at atmospheric pressure showed an adiabatic flame temperature above 2000°K.

Interpretation of results:

not classified based on GHS criteria

Conclusions:

R-12 did not show flame propagation when tested in air at 101 kPa and 21°C. No flammable range could be determined. It is therefore considered non-flammable at atmospheric pressure according to ANSI/ASHRAE standard.

Description of key information

No flammable range was determined at 21°C and standard atmospheric pressure.

Key value for chemical safety assessment

Flammability:

not classified

Additional information

Dichlorodifluoromethane has a history of use. It has been assessed under UN Transport Regulation (ADR/RID/ADN) and assigned UN Number 1028 in the Dangerous Good List. Gases under pressure are listed in Class 2. Dichlorodifluoromethane is assigned UN class 2.2 : non flammable, non-toxic gas, and with ADR/RID classification code 2A (asphyxiant).

Justification for classification or non-classification

Dichlorodifluoromethane is not capable of propagating flame, and is considered non-flammable and non-combustible based on historical data. No flammable range was determined at 21°C and standard atmospheric pressure.