(1) A digger derrick manufactured after 1 January 1987 must be designed and manufactured in accordance with ANSI/ASSP Standard A10.31, Safety Requirements, Definitions and Specifications for Digger Derrick, applicable at the time it was manufactured.A “digger derrick” means an apparatus equipped with a hydraulic boom, mounted on a carrier vehicle and designed specifically to drill holes and install posts in the ground and, by means of an aerial device, install the material to be supported by the posts.