Double Leaf Blast Doors

American Safe Room manufactures these pre-hung blast resistant double leaf doors that are engineered to protect your shelter from the high pressure blast waves produced by a large conventional or nuclear detonation.

A double leaf blast resistant door has two swinging door leaves mounted on one frame. It is designed to allow vehicles to pass through while carrying the same pressure rating as our single leaf blast door. If your shelter has the ability to house a vehicle, you need this door. Please measure the height and width of your vehicle before ordering.

Standard and custom sizes

This door comes in two standard sizes – and we’ve built many customer sized doors. The standard sizes are 72 inches wide by 80 inches tall and 96 inches wide by 80 inches tall. The free opening when installed is nominally one half inch under the rated size.

Certified Load Rating

These doors are certified by a professional engineer to withstand a 50 PSI (3 bar) blast load in the seated condition and 14.5 PSI (1 bar) rebound load in the unseated condition.


Rebound Load

The door has been engineered to withstand the “negative pressure” force (less than atmospheric) that sucks the door outward right after the blast wave passes over. A detonation blasts all the atmosphere outward, leaving little or no atmosphere for a very short amount of time. This “negative pressure” has energy and can be as deadly as the high-pressure blast wave. That is why our blast doors have the rebound load rating and our automatic blast valves are double acting for both pressure and vacuum.

This is a custom 12 foot high double leaf blast door with no top frame rail and a flat threshold. It is used in a blast containment room in a foundry where crucibles can be either rolled over the flat threshold or hoisted through the open top with a bridge crane.

Protection

These doors are also designed to protect against malicious people and fires. The door features four inches of concrete that resists structural fires, cutting torches, and has a UL level 8 ballistic rating – multiple hits with a 7.62 NATO round with no penetration.

Latches

The cam latches are rotating handles on the inside of the door leaf that engage a cam welded on the top and bottom frame rail. They are fabricated from plasma cut and formed quarter inch steel plate. They operate in opposite directions in case the door is moved in a blast – one may loosen, but the other one will tighten, holding the door in place. They feature adjustable tension bolts that keeps the handle in whatever position you leave it.

Optional outside operators

A lot of our double leaf blast doors are installed in industrial applications that require the door latches to be operated from either side of the door. As an option, we install outside cam latch operators that feature a shaft that goes through the door leaf with a handle on the other side that rotates the cam latches. This door has four outside operators and two pull handles on the outside. Outside operators are not suitable for shelters or other high security installations.

Compression seal

Double leaf doors do not have an airtight seal between the leaves. They allow more air leakage than single leaf doors, but they do feature a synthetic rubber seal between the door and the frame allowing for the use of a positive pressure NBC filtration system inside the shelter. The inside cam latches draw the door into the seal as they are rotated. This puts the seal under compression between the door leaf and the frame. The strict tolerances we hold allow us to use a closed cell EPDM foam seal – not the bulb (automotive type) seal commonly used when manufacturers can’t hold the tolerance necessary for a solid seal. This seal is expertly applied without stretching it and the corners are cleanly chamfered to seal out airborne toxins. As an option, you can get a second, fire rated seal applied outside of this primary one. Any fires outside your shelter will have to burn through the fire seal before they get to the primary seal.

Prices, availability, and ordering
There are two standard sizes and seven options:

72 x 80 inch blast door – $7,050, plus options and shipping 
96 x 80 inch blast door – $7,650, plus options and shipping
Custom sizes – quoted upon request

Option – inward swinging door leaf – $550
Option – outside operators (cam handles) – $1,150
Option – assault resistant cam latches – $1,150
Option – security hasp assembly – $225
Option – wide angle viewer – no charge
Option – differential pressure gauge – $325
Option – additional fire rated door seal – $350

How to order: page five of the manual has a worksheet that walks you through generating a part number that shows the size and options. You can e-mail or FAX the part number in with a delivery address and we will return a quotation – usually the same day. Financing is available for this item – just send the one minute credit application in to Partners Capitol Group.

Special order item: We usually need four weeks of build time. You arrange a 50% deposit at time order, we build the part, you arrange payment for the balance due, and we ship it right out and send you the tracking number. See our policy page for the full set of terms.

We’ve placed a lot of these doors in industrial applications: chemical plants, foundries, ordnance storage magazines, ordnance testing ranges, refuge chambers, and even a rhinoceros enclosure at a zoo. See this page on our dedicated blast door website for a list of these doors. If you have an application that needs to protect from, or to contain a detonation, please contact our sales department at 541-459-1806 or sales@AmericanSafeRoom.com