Standard Refrence

If you don't have any local safety codes to follow, you could follow:

ASME B30.20 Below the Hook Lifting Devices

• Volume B30.20 includes provisions that apply to the marking, construction, installation, inspection, testing, maintenance, and operation of below-the-hook lifting devices, other than slings, used for attaching loads to hoist. The devices are arranged in four chapters as follows: Chapter 20-1: Structural and Mechanical Lifting Devices. Chapter 20-2: Vacuum Lifting Devices. Chapter 20-3: Operated Close Proximity Lifting Magnets. Chapter 20-4: Remotely Operated Lifting Magnets.

ASME BTH-1 Design of Below the Hook Lifting Devices

• BTH-1 provides minimum structural and mechanical design and electrical component selection criteria for ASME B30.20 below-the-hook lifting devices. The provisions in this Standard apply to the design or modification of below-the-hook lifting devices. Compliance with requirements and criteria that may be unique to specialized industries and environments is outside of the scope of this Standard. Lifting devices designed to this Standard shall comply with ASME B30.20, Below-the-Hook Lifting Devices. ASME B30.20 includes provisions that apply to the marking, construction, installation, inspection, testing, maintenance, and operation of below-the-hook lifting devices. ASME BTH-1 addresses only design requirements. As such, this Standard should be used in conjunction with ASME B30.20, which addresses safety requirements. ASME BTH-1 does not replace ASME B30.20. The design criteria set forth are minimum requirements that may be increased at the discretion of the lifting device manufacturer or a qualified person.