Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Physical & Chemical properties


Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Flammability: extremely flammable gas

Key value for chemical safety assessment

extremely flammable liquified gas

Additional information

The flammability in air of dichlorosilane was determined using the "bomb" method in accordance with DIN EN 1839 test method and in compliance with ISO 17025 quality system. A 10 L spherical pressure vessel which was electrically heated was used for the tests at a temperature of 25°C. Under the condition of the study, the Lower Explosion Limit (LEL) of dichlorosilane was observed to be 2.8 mol.% (± 0.1 vol.%).

In available secondary sources to which reliability could not be assigned, LEL of 3.0% at 35°C and UEL of 10% at 65°C were reported for dichlorosilane. Similarly, LEL of 2.5% (V) and UEL of 80% (V) were reported for the substance.

As the registration substance is an extremely flammable gas, it is not appropriate to test for flammability in contact with water; nor is it necessary to classify the substance for this endpoint. Nevertheless, the related substance trichlorosilane is known to produce a flammable gas (hydrogen) in contact with water at a rate of gas of more than 10 l/ (kg min), determined in a test conducted according to UN Test Method N.5. It is therefore reasonable to conclude that in contact with water, dichlorosilane would also liberate hydrogen gas at a rapid rate.

Justification for classification or non-classification

The substance is classified as follows:

Classification and Labelling according to EC Regulation (No.) 1272/2008: Flam. Gas 1; H220 Extremely flammable gas.

Classification and Labelling according to Regulation (EC) No. 1272/2008: Liquefied gas; H280: Contains gas under pressure; may explode if heated