Abstract: A combustion apparatus comprising: a device for mixing a fuel with an oxidant; a combustion chamber in which combustion of the fuel/oxidant mix takes place; a pre-chamber located between the device and the combustion chamber; and means for supplying a gas to the pre-chamber so as to form a film of gas on the interior surface of the pre-chamber so as to prevent a combustion flame from the combustion chamber attaching itself to this interior surface damaging the pre-chamber, the supply of gas to the pre-chamber being such that where the gas first reaches the interior surface of the pre-chamber it forms a substantially continuous film of gas over this interior surface.