Most people's impressions of the inside of ducts come from action movies. Heroes gain access or victims find escape through rows of pristine ducts. However, movie ducts have no obstructions or protruding objects to inhibit travel within them. Ducts are connected at each joint with screws or steel rivets that protrude into the ducts.

 Steel rods may be placed at various intervals through the ducts to keep them from collapsing. Volume dampers may be placed at any point in a duct to moderate the air flow. Turning vanes are placed at elbow joints to assist air in turning corners. All of these obstructions assist in the buildup of contaminants inside ducts, so it's important you know what is inside your ducts and how you can handle it.

What contaminants can accumulate inside ducts?

​Although filters are used to clean the air that blows through ducts, microscopic allergens can still infiltrate ducts and create heath issues for individuals suffering from allergies or asthma.

Improperly sealed connections or loose screws can allow moisture to enter ducts, allowing mold to form around protrusions inside ducts, and then spread throughout the system. Mold spores can present a serious health hazard for infants and the elderly, as well as individuals with compromised immune systems.

Insects and other pests can infest ducts and create accumulations of excrement that can dry and become airborne with sufficient air flow. They can also build nests around protrusions inside ducts. 

Poorly installed fiberglass insulation inside ducts may allow fiberglass fibers to enter the air, causing skin and eye irritation.

Pet hair may accumulate around vents and inside return ducts that draw air from inside a home. Accumulated pet hair around vents and duct connections may cause a concentration of pet allergens.

How are contaminants removed by duct cleaning?

Professional duct cleaners have powerful vacuums with special attachments that can navigate through ducts, and they are familiar with the signs of mold or pest infestation. If there are blockages, duct cleaning specialists will use a camera equipped probe that can be snaked through a series of ducts to discover possible issues.

Duct cleaning services may not perform services such as mold remediation, pest control, or duct replacement. However, they can diagnose the problems for you so you can hire the appropriate contractor to eliminate the cause of duct contamination if one is present. If you need to hire a subcontractor for issues such as mold remediation, be sure to have your duct system sealed to keep moisture out. This will help to minimize future occurrences. Find more information here.