You probably don't
think about door closers very much in your lifetime,
but they are a very important piece of machinery in
fire prevention. They do not just close doors - which
may seem obvious, but they have a variety of functions.
 Opening
the door compresses a spring or a nest of springs which
are then permitted to decompress at a controlled rate
by the flow of hydraulic fluid through a piston and
valves thus closing the door. Of course there is a variety
of standards in the door closer market. A good door
closer should be efficient, smooth, easy to operate
and last for many years. If it is poorly made it will
be unreliable and difficult to use. To be efficient
the door must not require too much force to pull it
open - just enough so the hydraulics have enough power
to close the door and keep it closed. The closer should
have a controlled closing method which can be adjusted
for the environment that it is in.
There are many other functions that
a door closer can perform, such as holding the door
open until a fire alarm is triggered, cushioning the
opening action of the door to prevent it slamming into
an adjacent wall and delaying the closing action to
allow trolleys etc. through.
When choosing which door
closer to buy there are several things to consider:
- Back up service and advice from
the vendor/manufacturer
- Price, high price does not necessarily
mean high quality, but if it is really cheap be careful
- Suitability for use on fire doors
- Standards
New European standards include
two performance standards for door closers - BS EN 1154
is for all door closing devices including surface mounted
overhead, concealed, floor springs etc. If it closes the
door in a controlled manner you can apply this standard.
BS EN 1155 is for door closers with integral electrically
powered hold open devices which hold the door open until
either the power fails or the fire alarm is activated.
The recommended text or format to look for on a product
to see if it has passed the European standards is - "this
product has been successfully type tested for conformity
to all the requirements of BS EN 1154 (or 1155)."
The manufacturers should also have test certificates.
 Of
course there are its aesthetic qualities to consider
as well. Who wants a great hunk of metal above their
well designed door frames. There have been great developments
in this area of design. Specifiers can now choose from
a wide selection of miniaturised door controls and operators.
There has also been improvements in safety issues such
as fire door control and smoke and heat ventilation.
The development of miniature chain drive units that
can be completely concealed within the window frame,
together with ventilation control gear that can be fitted
flush to window frames, provides a practical, safe and
unobtrusive solution to the automatic opening and closing
of windows. This ensures rapid evacuation of smoke and
heat in the event of a fire. Architects now have much
more freedom to design because the hardware mechanism
hardly enters into the room because it is so small.
Specially designed spindle drives
can now be fitted in almost any type of curtain walling.
The development of a super slim electric sliding door
opener should soon be available, at only 7cm high it
will not even be noticeable in the building façade.
Swing door operators have also been miniaturised. They
can enable you to open a 160 kilo door with one hand.
Soon, door closers will be invisible, built into the
door itself. As an industry many individuals are striving
to reach new goals and technologies. We are currently
going through an architectural revolution and many new
innovative technologies are being developed. It has
been shown that if one manufacturer has a cutting edge
technology door closer available he is likely to be
given the ironmongery contract for the rest of the building.
To be at the forefront of technology requires concentration,
dedication and specialisation, there must be trust between
a progressive manufacturer and the architectural ironmonger.
|
