File:Air duct.jpg

DescriptionAir duct.jpg English: Ducts (HVAC) in ceiling. 中文（繁體）：天花板的中央空調風道 Date 31 May 2011 Source Own work Author Mk2010

https://creativecommons.org/licenses/by-sa/4.0CC BY-SA 4.0 Creative Commons Attribution-Share Alike 4.0 truetrue English Industrial Air Duct Cleaning in Surrey

English Air duct pipes at Viborg Katedralskole, Denmark. Wikimedia username: W.carter URL: https://commons.wikimedia.org/wiki/user:W.carter author name

Creative Commons Attribution-Share Alike 2.0 Generic license. Attribution: Air Duct Manufacturing, Scotts Garage Services and K&S Recovery Services - Kilmarnock

BY-SA 4.0 Creative Commons Attribution-Share Alike 4.0 truetrue English Air duct cleaning is an essential aspect of maintaining a healthy and comfortable