This paper reviews the safety of the operation of conventional engines on various alternative fuels. It is shown that methane in the form of compressed natural gas (CNG) is a safer engine fuel than common gasoline or other alternative fuels such as propane or hydrogen. The paper also describes the safety procedures adopted in the design and operation of a conventional laboratory engine on rich mixtures of methane and oxygen enriched air for hydrogen and synthesis gas (i.e. CO + H2) production.