Establishes minimum regulations for mechanical systems using prescriptive and performance-related provisions. First introduced in 1996, the IMC was developed with broad-based principles that make possible the use of new materials, methods and design. Changes include:
- New and existing mechanical systems must be maintained in accordance with ASHRAE/ACCA/ANSI Standard 180.
- Parking garage exhaust now defined as environmental air.
- Includes specifications for grease reservoirs in commercial cooking exhaust duct systems.
- Includes requirements for underground grease ducts.
- Requires any combustible material in a return air plenum to be listed and labeled to verify compliance with ASTM E-84 or UL 723.
- Air dispersion systems are now allowed.
- New requirements for evaporative coolers.
