Establishes the Missouri Statewide Mechanical Contractors Licensing Act

SB 957 creates a statewide licensing system for mechanical contractors in Missouri, replacing local licenses with uniform requirements. It defines "mechanical work" broadly to include HVAC systems, boilers, fuel piping, and refrigeration (excluding wood stoves, fire sprinklers, and some residential replacements), and establishes statewide licenses for contractors, journeyworkers, and apprentices. The Division of Professional Registration will manage licensing, including education requirements, fees, and renewals, while exempting minor residential repairs in single-family homes or small apartments. This bill directly affects contractors, apprentices, and businesses performing mechanical work across all Missouri jurisdictions.