The devil is in the detail...

Richard Richardson-Derry of GEZE UK looks at how a properly fitted fire door with the appropriate components can give occupants vital time to escape in the event of a fire.

Despite what most people believe, toxic smoke is the cause of the most deaths in fires, as opposed to the fire itself. So what constitutes a fire door?

The BWF Fire Door Alliance states the term usually refers to a fire door leaf which is the main component installed into a fire-rated frame, along with ‘essential ironmongery’ to make the door perform correctly in the event of a fire.

However therein is the challenge – when not required to be a fire door it must still perform everyday functions of providing safety, security, privacy, separating different areas and reducing noise in a building.

When an architect specifies door products, it is imperative that as well as achieving the everyday design requirements, factors relating to fire resistance are also a key consideration in order to achieve regulatory compliance.

Under the spotlight

Apart from the frame and door leaf, a fire door includes a door closer, smoke seals, hinges, push pads or handles, signage, and maybe a vision panel. Each and every component must be fit for purpose; should any component fail then the whole fire door assembly could fail. And any item that is badly fitted or wrongly specified could contribute to the spread of fire.

For each part of the fire door there are standards that must be adhered to.

The door and frame should be installed securely and plumb and true with a maximum gap of 3 mm to all sides for a fire door with smoke protection (for a general fire door the gap can be up to 10 mm).

The door closer is an important part of the fire door assembly and it is critical to specify a suitable unit and ensure minimum size EN 3 is used.

All doors must be fitted with intumescent seals – they play a major role in fire safety as they will expand to around 10 times their volume when significant heat is applied.

Hinges are a critical part of a door, carrying its weight and allowing free movement of the door leaf but also helping to keep the door straight during a fire episode. There should be three hinges in a fire door up to 2,100 mm high. For doors over 2,100 mm high, exceeding 150 kg, or over 100 mm wide there should be four. All hinges for fire doors should be made of steel or stainless steel and have a melting point of no less than 800°C.

All relevant push pads, handles and kick plates must have the required test data and standards and should have a melting point of at least 800°C. Locks need to comply with BS EN 12209 and lever handles with BS EN 1906.

Signage on a fire door is required, such as ‘Fire Door Keep Shut’ or ‘Fire Door Keep Locked’. They need to conform to BS 5499: ISO 7010.

Vision panels can be introduced to a door specification for reasons of safety, aesthetics, or to allow transfer of light, however the relevant seals must still be used so as not to compromise the integrity of the fire door and only suitable fire tested glass should be used.

Specifying a closer for a fire door

There are four main types of closer – surface mounted with link arm, surface mounted with guide rail, concealed, and floor mounted closer. All should be tested, approved and certificated to harmonised standard EN 1154, BS EN 1634-1 and have Certifire or similarly approved testing. In addition, a closer should be CE marked or hold the new UKCA (UK Conformity Assessed) certificate (effective from

January 2023).

There is also the application to consider: which closer is best suited to the door type, size, location and intended use of the door? Another consideration is the best fitting arrangement, and again this is dependent on door type, size, location and use.

There are several different configurations for a variety of applications that also need to be taken into account including fitting configurations, using brackets, mounting plates or spindle extensions to overcome specific site details. All should be specified in accordance with test evidence.

Another consideration is being able to adjust the closer. The correct adjustment of the closing force is needed to ensure it meets the requirements for access under Part M and BS 8300 with Part B of the Building Regulations for fire as well. Correct adjustment refers to electro hold open, back check, closing speed, and latch action to ensure the door opens and closes safely and securely.

All door closers complying with EN 1154 will have a six figure classification which should be marked on the door closer.

The power of door closers according to the EN 1154 standard are rated from one to nine, for example a size three door closer has a closing force of 18 Nm (Newton Metres), where Nm is the closing force exerted by the door one metre from the hinge point. It should be noted that the minimum size allowed for any door closer on a fire door is size three.

In summary, while all the component parts of a fire door must be thoroughly tested and conform to all relevant standards, the most important aspect is that they must work together as a doorset.

Richard Richardson-Derry is national specification manager for GEZE UK