Unauthorized personnel should not be permitted to ride on powered industrial trucks. Workers should never be lifted on the forks, a pallet, or any other inappropriate lifting device.
Also, hard hats are required where falling objects may create a hazard.
30 CFR § 56.9200 Transporting persons.
30 CFR § 56.14211 Blocking equipment in a raised position.
30 CFR § 56.15005 Safety belts and lines.
30 CFR § 77.405 Performing work from a raised position; safeguards.
30 CFR § 77.1601 Transportation of persons; restrictions.
30 CFR § 77.1710 Protective clothing; requirements. [see subparts (d) & (g)]