When it comes to air duct repairs, there are certain regulations that must be followed in order to ensure safety and efficiency. According to Section 608 of the Clean Air Act, it is prohibited to intentionally release (ventilate) any refrigerant when maintaining, repairing, or discarding air conditioning or refrigeration equipment, including MVAC systems. Technicians who repair or service MVAC systems must be certified under Section 609 of the CAA and must use refrigerant handling equipment that has been certified by the EPA or by an independent standards testing organization approved by the EPA. New service shops or workshops servicing MVAC systems for the first time must certify to their regional EPA office that they have properly purchased and are using approved refrigerant handling equipment. Air duct cleaning service providers may suggest applying a chemical biocide to the inside of the ducts to kill bacteria (germs) and fungi (mold) and prevent future biological growth.
Some pipeline cleaning service providers may propose introducing ozone to remove biological contaminants. Ozone is a highly reactive gas that is regulated in outdoor air as a lung irritant, and there is still considerable controversy over the need and appropriateness of introducing chemical biocides or ozone into pipelines. When it comes to air conditioning and mechanical ventilation systems, Clause 7.1 of the Code states that they must meet all relevant requirements for mechanical ventilation systems. The air conditioning system must have a surface flame spread index not lower than class 1, generate a minimum amount of smoke and toxic gases when involved in a fire, and be at least 1 m away from a fire absorber. Flexible joints and connections must not exceed 4 m.Fire dampers are not required in ducts that penetrate vestibule enclosures if a masonry slab is constructed below the duct to serve as the roof of the compartment.
The masonry slab above the vestibule completes the compartmentalization, making the vestibule a safe area. Ventilation ducts must not pass through smoke-free vestibules or fire elevators. Air conditioning ducts or other ventilation ducts must be constructed of steel, aluminum, fiberglass wadding or mineral wool, or other approved materials. They must also be properly supported. When it comes to penetrating separating walls, ducts are prohibited from doing so in order to prevent fire from spreading from one building to another. In commercial houses with a terrace, air conditioning ducts should not be shared.
The control panels that serve smoke control and smoke purge systems must be clearly visible and located in a common place easily accessible for operation and maintenance, preferably within the circulation space with a mounting height of not less than 1.5 m and not more than 1.8 m from the finished floor level. If it is not possible to find a commonly accessible place, the control panels must be protected with a fire resistance index of at least 1 h.Plastic and foam insulation used in air conditioning systems must be self-extinguishing and covered or enclosed in a metal sheath or hybrid plaster or other fireproof coating material. This is due to the fact that fires occurring in hidden spaces can be difficult to detect and can produce smoke and toxic gases.
