由於葵青區缺少由長安邨來往葵盛及荃灣並途經葵泰路，此路線可吸納一些葵青工業區前往葵盛及荃灣等地，路線 42 是由長安邨至荃灣西站，路線 42A 則由長安邨至葵盛東。並於 2011 年 3 月 23 日正式開辦。此兩條路線均設有空調巴士及非空調巴士行走。

       As Kwai Tsing Disctrict lack of route from Cheung On Estate to Tsuen Wan and Kwai Shing and via Kwai Tai Road , this routes can attract some of the Kwai Tsing Industrial Area citizen to Kwai Shing and Tsuen Wan etc. , Route 42 is from Cheung On Estate to Tsuen Wan West Station , Route 42A is from Cheung On Estate to Kwai Shing East . This routes will open on 23/3/2011 . The routes are with Air-Conditioner Bus and Non-Air-Conditioner Bus .