The Ontario Building Code | Crane-Supporting Structures and Impact of Machinery and Equipment
4.1.5.11. Crane-supporting Structures and Impact of Machinery and Equipment
(1) The minimum specified load due to equipment, machinery or other objects that may produce impact shall be the sum of the weight of the equipment or machinery and its maximum lifting capacity, multiplied by an appropriate factor listed in Table 4.1.5.11.
Table 4.1.5.11.
Factors for the Calculation of Impact Loads
Forming Part of Sentence 4.1.5.11.(1)
| Item | Column 1 Cause of Impact | Column 2 Factor |
| 1. | Operation of cab or radio-operated cranes | 1.25 |
| 2. | Operation of pendant or hand-operated cranes | 1.10 |
| 3. | Operation of elevators | (1) |
| 4. | 1.20 | |
| 5. | supports for reciprocating machinery (e.g. compressors) | 1.50 |
| 6. | supports for power-driven units (e.g. piston engines) | 1.50 |
Notes to Table 4.1.5.11.:
(1) See ASME A17.1 / CSA B44, "Safety Code for Elevators and Escalators."
(2) Crane-supporting structures shall be designed for the appropriate load combinations listed in Article 4.1.3.2.
(3) Crane runway structures shall be designed to resist a horizontal force applied normal to the top of the rails equal to not less than 20% of the sum of the weights of the lifted load and the crane trolley, excluding other parts of the crane.
(4) The force described in Sentence (3) shall be equally distributed on each side of the runway and shall be assumed to act in either direction.
(5) Crane runway structures shall be designed to resist a horizontal force applied parallel to the top of the rails equal to not less than 10% of the maximum wheel loads of the crane.