Safety & Security
The common perception of glass as a dangerous material is not unfounded.
Standard annealed glass breaks relatively easily and fractures into potentially lethal shards or splinters. With safety being of paramount importance, it is perhaps not surprising that there are standards and regulations which govern the major areas of concern when glass is used in safety critical locations.
The architectural use of safety glazing is primarily governed by British Standard BS 6262: Part 4. BS 6262 is a national standard applying to all glazing work, including replacement glazing. BS 6262 identifies critical locations in general terms only and sets the minimum standards of glazing materials acceptable for use in these areas.
Additional guidance is also provided by Building Regulations appropriate to the country – i.e. Approved Document K for England, Approved Document N for Wales, Part V for Northern Ireland and Part P for of the Building Standards for Scotland. Compliance with BS 6262: Part 4 will also satisfy the requirements of Regulation 14 of the Health and Safety atWork Act.
Safety glass is defined by EN 12600 as glass which must have passed an impact test and either must not break or must break safely.
In both old and new buildings, glass sometimes used as guarding to “protect a change in level” and to stop people from falling. Such guarding may be a balustrade but can also be a window or screen close to floor level.
These situations are controlled by BS 6180 and must resist the loading determined in EN 1991-1-1 and its National Annex and PD 6688, as well as the relevant Building Regulations for the country involved.
The safe use of glass in tables and other furniture is controlled by EN 12521 and EN 14749. These are complex documents that should be held by furniture manufacturers.
The use of glass in overhead situations is not directly governed by a British Standard but guidance is provided by BS 5516: Code of practice for design and installation of sloping and vertical patent glazing.
There is no statute or British Standard that requires the use of security glazing. Rather, the building user or designer will specify its use.
The specifier must, therefore, identify whether a risk exists and decide upon the appropriate level of protection. There are however standards for different types of security glass. Security glasses are defined as glasses that afford protection against a specified level of attack.
They can be divided into three main groups:
1) Glass resistant to manual attack
2) Bullet-resistant glass
3) Explosion-pressure-resistant glazing
Glass resistant to manual attack is designed to provide protection against attack for example such as might be made by a person armed with an axe, crowbar or pick axe, and to delay access to the protected space for a short period of time. This type of glass is governed by the European Standard EN 356.
For more detail on the use of security glass and for product information please contact Dual Seal Glass technical advice centre.
Bullet resistant glass is designed to provide protection in two ways:
1) By preventing the passage of bullets from handguns, rifles and shotguns.
2) By protecting personnel against injury from splinters of glass which may fly from the rear surface of the glass.
This type of glass is governed by the European Standard BS EN 1063.
The explosion-pressure-resistant glazing category of security glazing is governed by the new European Standard EN 13541: Testing and classification of resistance against explosion pressure. Although this standard is in place, it remains the responsibility of the specifier to identify the level of risk of explosion and decide on the appropriate level of protection.
While there is no statutory requirement to use security glazing, there is a British Standard that covers its installation. BS 5357: Code of practice for installation of security glazing, provides guidance to glazing, framing and support for the following:
1) Security glazing resistant to manual attack
2) Bullet-resistant glazing
3) Complete installations
It places particular emphasis on: frame strength and its ability to hold the glass in place; the support to the frame; the protection provided by other elements such as counter fronts and tops.
The installation of glazing and fixing techniques other than that for security must comply with the recommendations of BS 8000: Part 0 & 7 Workmanship on building sites, and of BS 6262, and those of the manufacturers of the framing and sealant systems. Further detail on the recommendations for the installation of glazing is provided in “Glazing” section of technical pages.