New to the 2009 International Mechanical Code:

• The outdoor air ventilation requirements of Chapter 4 have been significantly revised to more closely reflect the requirements of ASHRAE 62. This will improve the indoor air quality performance of systems designed to the International Mechanical Code and allow for some reductions in the amount of outdoor air required.
• The maximum length of a clothes dryer duct was increased from 25 feet to 35 feet to provide more flexibility in the location of clothes dryers in a building.
• A new Section 1101.10 was added to require locking access caps on outdoor refrigerant systems to prevent children from having easy access to the refrigerant for purposes of inhaling. In an attempt to get "a buzz," many children have died from inhaling the refrigerants.