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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
explosive properties of explosives
Type of information:
experimental study
Adequacy of study:
key study
Study period:
05.02.2019
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
test procedure in accordance with national standard methods
Qualifier:
according to guideline
Guideline:
other: CLP, Annex I, Part 2, paragraphs 2.1.4.2 and 2.1.4.3
Qualifier:
according to guideline
Guideline:
other: Appendix 6 of the UN Recommendations on the Transport of Dangerous Goods, Manual of Tests and Criteria
Qualifier:
according to guideline
Guideline:
other: Technical Guidance Document on the Information Requirements for REACH, Part 2 EWG 1-7, REACH Implementation Project (RIP) 3.3 Phase 2, chapter 7.1.11.3
GLP compliance:
no
Key result
Parameter:
other: Oxygen balance
Remarks on result:
other: oxygen balance is calculated to -24.99
Key result
Parameter:
other: Decomposition energy
Remarks on result:
other: The curve displays one exothermic peak between about 80 °C and 115 °C with a total energy release of about 150 g/J

Screening evaluation

No experimental test data according to EU Method A.14 or comparable methods for methylphosphonic acid are available.

Considering that explosive properties are associated with the presence of certain chemical groups in the molecule, a screening evaluation can be conducted aimed to identify the presence of such reactive groups within the molecular structure harvesting the capability for a rapid high energy release.

According to CLP Regulation examples of groups which may indicate explosive properties are:

-       C-C unsaturation (e.g. acetylenes, acetylides, 1,2-dienes);

-       C-Metal, N-Metal (e.g. Grignard reagents, organo-lithium compounds);

-       Contiguous nitrogen atoms (e.g. azides, aliphatic azo compounds, diazonium salts, hydrazines, sulphonylhydrazides);

-       Contiguous oxygen atoms (e.g. peroxides, ozonides);

-       N-O (e.g. hydroxyl amines, nitrates, nitro compounds, nitroso compounds, N-oxides, 1,2-oxazoles);

-       N-halogen (e.g. chloramines, fluoroamines);

-       O-halogen (e.g. chlorates, perchlorates, iodosyl compounds).

Analysis of the molecular structure revealed, that no chemical structures representing chemical alert structures for explosive properties are present in the molecule.

Calculation of the oxygen balance according to the above-mentioned formula is -24.99 and therefore higher than the trigger value of -200.

Determination of the exothermic decomposition energy

In order to assess if the substance methyl phosphonic acid possesses the potential to rapidly release huge amounts of energy a thermal analysis (Differential Scanning Calorimetry) has been performed. The results of the measurement are shown in Annex 1.

The curve displays one exothermic peak between about 80 °C and 115 °C with a total energy release of about 150 g/J. This peak is considered to represent the release of water. As a result, energy release is below the critical trigger level of 500 J/g and the onset of energy release is below 500 °C.

Interpretation of results:
GHS criteria not met
Conclusions:
In summary, analysis of the chemical structure reveals no alerts for explosive properties. The calculated chemical oxygen balance is above the trigger value of -200 but the determination of the exothermic decomposition energy demonstrated an energy release below the critical value of 500 J/g. Therefore, the substance is considered to be non-explosive according to Directive 67/548/EEC and Regulation (EC) 1272/2008 and no further testing is required.
Executive summary:

In summary, analysis of the chemical structure reveals no alerts for explosive properties. The calculated chemical oxygen balance is above the trigger value of -200 but the determination of the exothermic decomposition energy demonstrated an energy release below the critical value of 500 J/g. Therefore, the substance is considered to be non-explosive according to Directive 67/548/EEC and Regulation (EC) 1272/2008 and no further testing is required.

Description of key information

Methylphosphonic acid (MPA) is an organic phosphorous substance with a very low volatility. The purified chemical is solid at room temperature forming white crystals. MPA has a flash point >200 °C. MPA does not contain chemical groups associated with explosive properties. Therefore, MPA is considered to be non-explosive.

Key value for chemical safety assessment

Explosiveness:
non explosive

Additional information

Justification for classification or non-classification

MPA does not contain chemical groups associated with explosive properties, therefore classification of the substance for explosive properties is not considered.