56.-(1) In every factory in which, in connection with any process carried on, there is given off any dust or fume or other impurity of such a character and to such extent as to be likely to be injurious or offensive to the persons employed, or any substantial quantity of dust of any kind, all practicable measures shall be taken to protect the persons employed against inhalation of the dust or fume or other impurity and to prevent its accumulating in any workroom, and in particular, where the nature of the process makes it practicable, exhaust appliances shall be provided and maintained, as near as possible to the point of origin of the dust or fume or other impurity, so as to prevent it entering the air of any workrοom.
(2) No stationary internal combustion engine shall be used unless-
(a) provision is made for conducting the exhaust gases from the engine into the open air; and
(b) the engine (except when used for the purpose of being tested) is so partitioned off from any workroom or part of a workroom, in which persons are employed other than persons attending to the engine, as to prevent any injurious fumes from the engine entering the air of the room or part of the room.