Propanenitrile, 2,3,3,3-tetrafluoro-2-(trifluoromethyl)-

Flammability

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

flammable gases

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 Aug 2020 - 24 Aug 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.11 (Flammability (Gases))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch number of test material: Lot 40
- Expiration date of the lot/batch: 17 Dec 2021

Key result

Parameter:

lower explosion limit

Remarks on result:

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

Key result

Parameter:

upper explosion limit

Remarks on result:

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

Remarks:

Spark suppression at concentrations ≥46% v/v

Spark Energy (mJ)	Gas Concentration (%v/v)	Ignition? y (yes) / n (no)	Comments
C/A	15	n	-
C/A	14	n	Multiple sparks observed
C/A	13	n	Multiple sparks observed
C/A	12	n	Multiple sparks observed
C/A	11	n	Multiple sparks observed
C/A	10	n	Multiple sparks observed
C/A	9	n	-
C/A	8	n	Multiple sparks observed
C/A	7	n	-
C/A	6	n	-
C/A	5	n	-
C/A	4	n	-
C/A	3	n	-
C/A	2	n	-
C/A	1	n	-
C/A	16	n	-
C/A	17	n	-
C/A	18	n	-
C/A	19	n	-
C/A	20	n	-
C/A	22	n	-
C/A	24	n	-
C/A	26	n	-
C/A	28	n	-
C/A	30	n	-
C/A	32	n	Forked sparking observed
C/A	34	n	Forked sparking observed
C/A	36	n	Forked sparking, red glow
C/A	38	n	Forked sparking, red glow
C/A	40	n	Forked sparking
C/A	42	n	Delayed forked sparking
C/A	44	n	Forked sparking
C/A	46	n	Spark supressed (no spark)
C/A	48	n	-
C/A	50	n	Spark supressed (no spark)

C/A = Constant (high energy) Arc from 15 kV transformer

Interpretation of results:

GHS criteria not met

Conclusions:

C4 F-isonitrile was determined to have no flammable range with air at 20 °C and 101.3 kPa (EU method A.11).

Executive summary:

The flammability of C4 F-isonitrile was evaluated according to EU Method A.11. Mixtures from 1% v/v to 50% v/v were tested. The test mixture suppressed the ignition spark at concentrations above 46% v/v and further testing was not feasible. No ignition was observed. This test was performed following EU guidance and was GLP compliant; therefore it is considered reliable without restriction.

Reference 2

Endpoint:

flammable gases

Type of information:

calculation (if not (Q)SAR)

Adequacy of study:

supporting study

Study period:

2020

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

Qualifier:

no guideline available

Principles of method if other than guideline:

Thermodynamic and quantum mechanical calculations

GLP compliance:

no

Remarks:

(Calculation method)

Parameter:

lower explosion limit

Remarks on result:

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

Parameter:

upper explosion limit

Remarks on result:

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

Interpretation of results:

GHS criteria not met

Conclusions:

C4 F-isonitrile has no flammable range in air at 25 °C and 101.325 kPa based on adiabatic flame temperatures calculations. No ignition is possible in atmospheres containing less than 25% oxygen.

Executive summary:

Upper and lower explosion limits were estimated for C4 F-isonitrile using thermodynamic calculation of the adiabatic flame temperature. This property measures the temperature attained on ignition of a flammable air-gas mixture when no energy is lost to the system. It is therefore the maximum theoretical temperature that can be attained. The temperature is a function of the enthalpy of reaction and the sum of the heat capacities of the components of the mixture (itself a function of temperature). Heat capacity was calculated for C4 F-isonitrile using ab initio molecular dynamics simulations. Reaction stoicheometry was assumed using results of thermal decomposition experiments. Critical reaction temperatures to define the lower and upper explosion limits were taken from the literature to be 1500 K and 1800 K, respectively. The approach was validated by comparison to methane. C4 F-isonitrile has no flammable range in air at 25 °C and 101.325 Pa. The limiting oxygen concentration for ignition of any mixture is 25.2%, below which ignition is not possible.

Description of key information

C4 F-isonitrile was determined to have no flammable range with air at 20 °C and 101.3 kPa (EU Method A.11).

Key value for chemical safety assessment

Flammability:

not classified

Additional information

The flammability of C4 F-isonitrile was evaluated according to EU Method A.11. Mixtures from 1% v/v to 50% v/v were tested. The test mixture suppressed the ignition spark at concentrations above 46% v/v and further testing was not feasible. No ignition was observed. This test was performed following EU guidance and was GLP compliant; therefore it is considered reliable without restriction. In support of this observation, thermodynamic calculations indicate that combustion of C4 F-isonitrile does not produce enough energy to attain a critical temperature for sustained reaction at any ratio in air. This agrees with the weight of handling experience, in that use of C4 F-isonitrile as an insulating gas in high voltage switchgear does not result in ignition despite arcing in the switchgear.

Justification for classification or non-classification

Not classified - conclusive but not sufficient for classification