Mandatory inspection intervals - none in the direct standard however there are some in the standards that rae incorporated by reference.
I have listed a few below.
Standards that include inspection information are incorporated by reference as specified in Sec. 1910.6:
National Fire Protection Association Standard for Drycleaning Plants, NFPA No. 32-1970;
National Fire Protection Association Standard for the Manufacture of Organic Coatings, NFPA No. 35-1970;
National Fire Protection Association Standard for Solvent Extraction Plants, NFPA No. 36-1967;
National Fire Protection Association Standard for the Installation and Use of Stationary Combustion Engines and Gas Turbines, NFPA No. 37-1970;
ASME Boiler & Pressure Vessel Code
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Obtain a copy of "National Board Inspection Code -- 2001 Edition --- NB-23"
This American National Standard is a required code in many jurisdictions of the United States and Canada. Provides rules and guidelines for inservice inspection of boilers, pressure vessels, piping and pressure relief valves. Also provides rules for the repair, alteration, and rerating of pressure-retaining items and repair of pressure relief valves. Serves as a manual for inspectors to help maintain uniform administration of boiler and pressure vessel rules. Now also includes "VR" requirements. (Technical) Required for all "R", "NR", "VR" and O/U certificate holders.
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You might want to contact your juridision's chief boiiler & pressure vessel inspector or your insurance company to find out what their requirements are.