3(1)All sums received by a builder or contractor or a sub-contractor on account of the contract price are and constitute a trust fund in the hands of the builder or contractor, or of the sub-contractor, as the case may be, for the benefit of the proprietor, builder or contractor, sub-contractors, Workplace Health, Safety and Compensation Commission, workmen and persons who have supplied material on account of the contract or who have rented equipment to be used on the contract site, and the builder or contractor or the sub-contractor, as the case may be is the trustee of all such sums so received by him, and until all workmen and all persons who have supplied material on the contract or who have rented equipment to be used on the contract site and all sub-contractors are paid for work done or material supplied on the contract and the Workplace Health, Safety and Compensation Commission is paid any assessment with respect thereto, may not appropriate or convert any part thereof to his own use or to any use not authorized by the trust.