(a) Notwithstanding subdivisions (3) and (4) of § 29-221, the following items are excluded from the scope of this chapter: (1) Machinery included in subdivisions (3) and (4) of § 29-221 while it has been converted or adapted for a nonhoisting or nonlifting use, including power shovels, excavators and concrete pumps, (2) power shovels, excavators, wheel loaders, backhoes, loader backhoes and track loaders, including when this machinery is used with chains, slings or other rigging to lift suspended loads, (3) automotive wreckers and tow trucks including rotators registered as wreckers and operated by a person, firm or corporation licensed as a motor vehicle dealer or repairer in accordance with the provisions of subpart (D) of part III of chapter 246 when used in such licensed business, whose functions may include consensual or nonconsensual vehicle recovery and load transfer and consensual or nonconsensual towing and transportation of wrecked or disabled vehicles from the point at which the accident occurred or the vehicle became disabled, (4) digger derricks when used for augering holes for poles carrying electric and telecommunication lines, placing and removing the poles and handling associated materials to be installed on or removed from the poles, (5) machinery originally designed as vehicle-mounted aerial devices for lifting personnel and self-propelled elevating work platforms, (6) telescopic or hydraulic gantry systems, (7) stacker cranes, (8) powered industrial forklifts, except when configured to hoist and lower, by means of a winch or hook, and horizontally move a suspended load, (9) mechanic trucks with a hoisting device when used in activities related to equipment maintenance and repair, (10) machinery that hoists by using a come-a-long or chain fall, (11) gin poles when used for the erection of communication towers, (12) anchor handling or dredge-related operations with a vessel or barge using an affixed A-frame, (13) roustabouts, (14) helicopter cranes, (15) propane service vehicles that are equipped with a crane to load or offload Department of Transportation (DOT) approved propane tanks or American Society of Mechanical Engineers (ASME) approved propane tanks having a capacity of two thousand gallons or less, (16) overhead and gantry cranes when used for non-construction-related work, and (17) dedicated drill rigs.

(b) Articulating or knuckle-boom truck cranes that deliver material to a construction site are excluded from the scope of this chapter when used to (1) transfer materials from the truck crane to the ground without arranging the materials in a particular sequence for hoisting, or (2) transfer building supply sheet goods or building supply packaged materials including, but not limited to, sheets of sheetrock, sheets of plywood, bags of cement, sheets or packages of roofing shingles and rolls of roofing felt from the truck crane onto a structure, using a fork or cradle at the end of the boom, but only when the truck crane is equipped with a properly functioning automatic overload prevention device.

(c) The exclusion set forth in subsection (b) of this section does not apply when (1) the articulating or knuckle-boom crane is used to hold, support or stabilize the material to facilitate a construction activity, such as holding material in place while it is attached to the structure, (2) the material being handled by the articulating or knuckle-boom crane is a prefabricated component including, but not limited to, precast concrete members or panels, roof trusses, prefabricated building sections such as floor panels, wall panels, roof panels, roof structures or similar items, (3) the material being handled by the crane is a structural steel member such as joists, beams, columns and steel decking or a component of a systems-engineered metal building, or (4) the activity is not otherwise excluded under subsection (b) of this section.