No explosives shall be shipped from, discharged at, brought to, or deposited upon any wharf or place except such place as the port captain or his authorised deputy shall from time to time direct and such wharf or place shall be barricaded off to the satisfaction of the port captain or his authorised deputy and the quantity of explosives to be conveyed to and allowed on such wharf or place shall be regulated by the port captain or his authorised deputy; no other goods or articles shall be handled in such wharf or place at the same time with explosives, and
no persons other than those actually engaged in or superintending the work of loading or unloading shall be allowed within the barricades.