This British Standard specifies requirements for eight classes of
petroleum fuels for engines and boilers used in agricultural, domestic
and industrial applications.
This British Standard does not preclude lawful use of one class of fuel
in an application designed for use with a fuel of another class. However
it is strongly recommended that only class C1 burner fuel is used in
flueless domestic appliances, and it is advised that tests or consultation
with the equipment manufacturer is carried out if fuel is to be used for
a purpose other than that for which it is classified in this British
Standard.