Fire-resistant doors: Understanding E, EW and EI

• News
• 26 February 2020

Fire-resistant doors: Understanding E, EW and EI

Fire protection is one of the most important elements in construction. So, when purchasing a fire door, it’s important to understand the fire-resistant classes – as it could save lives. When a fire-resistant door has been tested, it is given a classification showing the duration of time it resists fire for. Split into different categories, the classes show how the door will prevent the passage of flames, smoke and heat transfer. This is represented as Integrity, Radiation or Insulation.

Integrity (E)

Integrity represents how long the door and its components can prevent the passage of flames and hot gases from the heated side of the door to the non-heated side. However, integrity ratings won’t prevent heat transferring through the door. Integrity is denoted as a letter “E”, followed by a number showing the number of minutes the door prevented flames and gases passing through to the non-heated side. For example, GLAS-DOR Glazed Doorsets are available with up to 90mins Integrity.

Radiation Control (EW)

Radiation maintains the same performance as Integrity – resisting flames and smoke when exposed to fire on one side. However, it will also prevent some of the heat from transferring from the heated side to the non-heated side. Radiation Control fire resistance is denoted as the letters “EW”, followed by a number showing the duration (in minutes) it will provide resistance. During the test, this is the duration it will keep radiant heat transfer below 15 kW/m² on the non-heated side.

Insulation

Insulation offers the highest level of protection from fire.  Maintaining the same performance as Integrity, Insulation also prevents any heat transferring from the heated side to the non-heated side. The letters “EI” represent Insulation, followed by the duration (in minutes) it provides fire resistance. For example, GLAS-DOR Glazed Wall Sections are available tested to EI 120 – meaning they will maintain both Integrity and Insulation for up to 120 minutes. Whereas GLAS-DOR Doorsets are available EI 90/60, meaning they will maintain integrity for 90 minutes, and Insulation for 60 minutes.  
Whether the building is residential, commercial or industrial, it is vital that the above standards are understood and followed. A fire door will compartmentalise a building, preventing a fire spreading and allowing people inside to evacuate. These standards are laid out in the UK building regulations and will go a long way to ensuring the protection of both people and property.