Yearly if your use is seldom, i.e. 1 to 10 trips up and down a month or less. 10 to 30 ( one a day max) then inspect every 6 months, more than that
or if many or most loads are close to maximum, every 3 months. The last condition is unlikely in the entertainment industry but "could happen"!
The above is our company policy and our advice to clients. It is a compilation of the recommendations of StageMaker, CM and Chain master maintenance manuals, and over 200 combined years of rigging experience of our rigging techs.
We don't have any clients with "permanently installed, load bearing hoists". We do have some with the hoists mounted in a permanent manner, but the loads are per event. The hoists are mounted above suspended ceilings or similar, and per event rigging would be excessively difficult and time consuming. The "permanent" mounting allows the chain hooks to be run in on a moments notice. We do bring them down and do a complete service check and inspection annually. If we are asked to install a permanent load using chain hoists, we will recommend other solutions such as
Line shaft hoists, Package hoists (PowerLifts, Vortek,
Prodigy, et. al.) Motorized
Clew winch, and plain drum hoists. Each has it's niche and in that niche is the best choice. In our opinion, chain hoists for permanent loads are acceptable but usually not the best choice.
At this
point in time there is no specific (USA) code or regulation that regulates inspection time frames. If we, as an industry, maintain a diligent and encompassing practice of maintenance, record keeping and
safety, there will never be a reason for any government entity to step in and regulate the use of chain hoists. On the other
hand, in Europe there is a great deal of regulation and they have a sterling
safety record (AFAIK).