18. The types of heating fuel oil are as follows:(1) type 0: intended for use in fuel domestic oil burning appliances that have outside storage in regions where ambient temperatures may reach - 48 °C;
(2) type 1: intended primarily for use in sleeve-type and wick feed burners and in most vapourizing pot-type and atomizing burners that cannot use type 2 heating fuel oil;
(3) type 2: primarily for use in domestic atomizing-type burners and is also intended for medium capacity commercial and industrial burners;
(4) type 4: an industrial type of fuel intended primarily for use in burners equipped with limited preheating devices or without preheating devices;
(5) type 5: a residual type of heating fuel oil for use in burners equipped with limited preheating facilities requiring a fuel oil of lower viscosity than type 6 heating fuel oil;
(6) type 6: a high-viscosity residual oil intended for use in burners equipped with preheating facilities.
All types of heating fuel oil must comply with Canadian General Standards Board standard CAN/CGSB-3.2-2013 - Heating Fuel Oil (Types 0, 1, 2, 4, 5 and 6).