Last week, Paula was delivering petrol to various garages in the South Wales area. This week she will be going up the coast to deliver heating oil to premises near Aberystwyth.
What must happen to the tank first?

Explanation: • It must be emptied of all petrol: No, this is not the best answer here.
• It must be washed out with water jetting equipment: No, water jetting may not be the best way of achieving a clean tank for these purposes.
• Nothing because it would be empty after her last delivery last week: No, this type of vehicle is not deemed "empty" until it has been "purged" of all traces of the previous load.
• It must be purged of its previous load: Yes, the proper term to use is "purged" - this ensures there is no element of the previous load remaining to contaminate any subsequent load. With ADR vehicles, they are not deemed "empty" until they have been "purged".

Category: CPC Case Studies: Technical Matters