Protection against impact with glazing. Part K identifies that impacts with glazing, particularly glazing in doors and side screens can result in cutting and piercing injuries, the risk being greatest between floor and shoulder level when near to the door handle or push plate. Critical location. In particular locations, glazing materials within doors or associated screens must limit the risk of cutting or piercing injuries in the event of breakage. Part K of the Building Regulations identifies these ‘critical locations’ and appropriate measures, including use of safety glass as defined in BS EN 12600 Section 4 and BS 6206 clause 5.3. In these locations, glazing should: a) A small opening only, with detached particles no larger than specified maximum size. b) Disintegration into small detached particles c) Broken glazing in separate pieces that are not large or pointed.
These requirements for glazing in doors and side screens are achieved, respectively, by: a) Minimum Class 3 of BS EN 12600 or Class C of BS 6206 (Class 2 or Class B respectively if the panel exceeds 900 mm in width) b) Use of inherently strong materials or annealed glass (subject to thickness/area limits), or small panes each no wider than 250mm and larger than 0.5m2 (minimum 6 mm thick for annealed glass, unless traditional lead or copper lights where 4 mm is permitted) c) Protection by an unclimbable, robust screen 800mm high from floor level which prevents a 75mm diameter sphere coming into contact with the glass. Part K also calls for the use of manifestation on large uninterrupted areas of transparent glazing, however, manifestation is not a requirement for flush or timber framed doors, or timber screens with less than 400 mm visible width, or a timber rail between 850 mm to 1000 mm and 1400 mm to 1600 mm above the floor. Protection against impact from and trapping by doors. Part K requires that to prevent the risk of impact or trapping, vision panels must be incorporated in door leaves and side panels wider than 450mm. Vision panels should be towards the leading edge and have minimum glazed zone(s) as shown, either with or without a horizontal rail.