About EW Rating
Class EW (Integrity & Radiation) rating is also a measure of Integrity performance, the ability to stop the spread of flames, smoke, and gasses through the unexposed side of a fire, with the addition of the ability to minimize radiant heat transfer from the fire side to the unexposed side. Class EW glass reduces the risk of fire transmission caused by radiant heat and thereby can allow for safer passage of building occupants making exit past the glass.
Class EW (Integrity & Radiation) rated glass is classified in accordance with European standard EN 13501-2, Fire classification of construction products and building elements, to withstand fire exposure from one side and ensure that the radiant heat transfer measured on the unexposed side of the glass remains below a specific value for a certain period of time. This time (the classification period) is declared in minutes using specific periods (30, 60, 90, etc…). A Class EW fire-rated glass with a 30 min classification period will be declared as EW30.
Performance criteria for EW = Integrity plus Radiation rating:
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No sustained flames on the side not exposed to fire
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No openings larger than Ø 25 mm or 6 x 150 mm
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Heat flux (radiation) not exceeding 15 kW/m² measured at 1 m distance
Related Classification
EI classification
Class EI (Insulation) fire-rated glass is the highest performance classification and acts as a barrier to heat transfer.
E classification
In the event of a fire, Class E (or Integrity only) fire-rated glass provides a barrier against the passage of flames, smoke, and hot, toxic gases.