The removal of scale from hard water from sinks, taps, toilet bowls, washbasins, baths, kettles and steam irons. All use some form of acid as the active ingredient.

A polyester resin, dissolved in styrene, is hardened by mixing with a catalyst. The resin is often used with glass-fibre reinforcement to give glass-reinforced plastic (GRP). Small scale repair kits use similar materials but with the catalyst supplied as a paste.

This document gives guidance to teachers and technicians that will be supervising a welding or plasma cutting facility.

Guidance on controlling the fumes from these operations can be found in GL326

Explains the relative merits of three different ways of producing printed circuit boards by etching copper-clad boards.