Circumstances requiring issuance.

The owner or lessee of a crane which is used to erect or dismantle a tower crane shall ensure that such a crane has been issued a valid certificate of operation by a certifying authority: 1. Before the crane is operated; and 2. Each time a crane which is used to erect or dismantle a tower crane is repaired or modified in any way which affects the structural integrity of the crane other than the addition of components which are a permanent part of the tower crane in its working condition, such as the jib, sections of the boom, a load block or rigging.