Fire, Blast, Sound and Super Insulated Doors

Flammable Combustible Liquid Codes require the doors of a hazmat building to be a step above a regular commercial grade door. A hazmat building common fire rated door has either a 1-1/2 or 3 hour rated construction. In truth, most door vendors make and have tested only one door which they label either 1-1/2 or 3 hour. The "1-1/2" rated door is for 2 hour fire rated buildings and the "3" rated door is for a 4 hour building. In theory, the rated structure should last longer than the door in a 2000° F fire. Below are three different fire rated doors, or combinations, with ever-increasing capability for different applications. First, there's the common fire rated door and then two levels of fire and blast rated doors (also have super sound qualities). Haz-Safe Buildings installs all doors within the wall's 1/4" thick tubular steel openings.

 

Common Fire Rated Doors

The common fire rated door is not blast rated. Door has a frame of 16 gauge steel with an 18 gauge skin front and back. It comes with a U.L. approved "B" and "C" labeled 1-1/2 hour or "A" labeled 3 hour fire rating. Each door is equiped with doorknobs and keyed cylindrical locksets and (3) steel ball bearing hinges. Available Features:

  • Low profile panic hardware
  • Closure with fusible link release hold-open device
  • Manual or automatic operated coordination door-closing device
  • Automatic gravity operated coordinating door-closing device

Pictures above and below show common fire rated doors from the outside closed position in first row and interior doors in the next row:

 

Blast and Fire and Sound Rated Doors

 The codes require the floor, walls, and roof to be fire and blast rated, but the doors only have to be fire rated. The blast rated building construction has to be 100lbs ft 2. Common fire doors are not constructed for (nor tested for) blast resistance. In the photo on the left, this is supposedly a picture of blast relief panels being tested in an explosion. The photo also shows the door on the right (leads to an adjacent room with the explosion) responding to the blast by being forced open. This door should have been blast rated. There are places when it is recommended the doors be both fire and blast rated, such as doors that lead from one hazmat room to another or a door from an attached hazmat building to the main facility. The blast requirement for the doors should exceed the wall requirement. For example, a 100lbs ft.2 wall requires 150lbs ft.2 doors because a person could be outside the door when there is an explosion and the door cannot suddenly fail to stay closed.

Upgrading the specifications from a common fire-only rated door to include a blast rating also adds strength and weight (mass), resulting in the door having accoustical capabilities for sound rating. The pictures below are doors that have
1-3/4" thick stressed steel structures without point loading with 18 gauge steel skins on 16 gauge steel horizontal stiffness on 12" centers. Doors have continuous locking channel and hinge. Any standard cam mortise cylinder works with their door levers. The fire rating is 1-1/2 and 3 hour for these doors that also are 130lbs ft.2. blast rated with a sound rating of 35 STC - operational 160lbs ft.2, and an STC of 40.

Other options are:

  • Low profile panic hardware
  • Sound and weather seals
  • Standard continuous locking channel and hinge eliminate need for vertical rods, top and bottom bolts, automatic flash bolts, door coordinators, astragals, etc.

 

Custom Blast Rated Doors

When there is a need for high security, the explosion proof doors pictured below are custom designed to provide the amount of blast rating required. The doors are inherently fire rated with high acoustical capabilities. The doors have as a minimum 14 gauge frames and skins and are equipped with stainless steel cam operating self-closing hinges very capable of compressing rubber seals. Many optional features are available.

 
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