Mechanically, this Order declares that chlorinated polyvinyl chloride (CPVC) pipes for fire sprinkler systems (tariff classification 3917.23.00) are goods to which Part III, Schedule 4 item 50 of the Customs Tariff Act 1995 applies. It takes effect from 6 December 2010 and continues until revoked under sections 269SC or 269SD. This change affects importers, customs officers and suppliers of the specified CPVC sprinkler pipe by altering the tariff treatment and related compliance obligations tied to that Schedule 4 item.