10. Where an employer receives from a supplier at a workplace a container that in turn holds one or more containers of a controlled product which the supplier has not labelled, the employer himself shall affix to those containers the label required by the Hazardous Products Act (R.S.C. 1985, c. H-3), if he has given an undertaking in writing to that effect to the importer, as provided for in section 14(2)(a)(ii) of the Controlled Products Regulations (SOR/88-66).