Regular inspections are required by OSHA and the CMAA (Crane Manufacturers Association of America). If you go 12 months without one, the manufacturer no longer has any liability, it all falls squarely on the owner.
Having worked for a large crane manufacturer and servicing companies such as International Paper, Duke Energy, GE, Airbus, and the U.S. Air Force, we have developed expertise in OSHA, CMAA, ANSI, and ASME compliance requirements.