Beware of Duct Cleaning companies that use inferior equipment !
DO NOT hire a duct cleaning company that uses equipment that is similar to the equipment shown, as it will not perform to the standards outlined below.
Below is an excerpt taken from the National Air Duct Cleaners Association's website...
"The most effective way to clean air ducts and ventilation systems is to employ Source Removal methods of cleaning. This requires a contractor to place the system under negative pressure (vacuum), through the use of a specialized, powerful vacuum. While the vacuum draws air through the entire ventilation system, devices are inserted into the ducts to dislodge any debris that might be stuck to interior surfaces. The debris can then travel down the ventilation system to the vacuum, which removes it from the system and the home".
A vacuum collection device alone will not get a ventilation system clean. The use of methods and tools designed to agitate debris adhered to the surfaces within the system, in conjunction with the use of the powerful vacuum collection device(s), is required to clean ventilation systems. (For example: brushes, whips, & skipper balls.)
Be Sure that your Duct Cleaning Contractor is using equipment that adheres to the above standards.