Sec. 23-1.27. Mechanical, hydraulic and pneumatic jacks

(a) Capacity marking.

The rated capacity of every jack in pounds or tons shall be legibly marked in a conspicuous location on the jack by casting, stamping, etching or other suitable permanent means. Such marking shall not affect the structural integrity of any jack.

(b) Overtravel.

Every jack shall be provided with a positive stop to prevent overtravel.

(c) Lubrication.

Every jack shall be maintained properly lubricated.

(d) Loads.

When an object or structure has been raised to a desired height by means of a jack, such object or structure shall be immediately blocked or cribbed.

(e) Use.

The use of any jack shall be at all times under the direct supervision of a designated person.