Blast resistant doors

The blast load and the required response. The load is normally given as peak reflected overpressure and positive-phase duration, or impulse, taken from the blast or siting study for the building. We also need the door size, swing direction, wall construction, whether the door must stay operable after the blast, and any fire rating or gas-tightness requirement. Without the load, any blast door is a guess.

Overpressure is the peak pressure the blast wave applies to the door face, and duration is how long the positive phase lasts. Impulse combines the two as the area under the pressure-time curve. A short, sharp load and a longer, lower load can do very different damage to the same door, so a peak pressure alone is not enough to specify it.

That is the owner's decision, written into the specification. Doors on control rooms and other occupied buildings are commonly required to stay operable so people can leave once the event is over, which makes them emergency exit doors in the most literal sense. That needs a stiffer leaf, hinges and locks that stay within their limits, and a frame that does not distort around the leaf.

Yes. Many control-room and substation doors combine blast resistance with a fire rating, and some need gas-tight seals so a positive-pressure room keeps out toxic or flammable gas. Each added function changes the construction, so state all requirements together at enquiry and ask for evidence that covers the complete door, not each function separately.

Lead time depends on the blast load, door size, any combined fire or gas-tight requirement and the level of design verification your project asks for. Within Jordan, doors are typically delivered within 1 to 2 weeks; for export, lead time depends on quantity. Send us the blast study data, door schedule and wall details, and we will confirm a programme with your quotation.