AMBICO blast resistant steel doors and frames combine blast and air pressure resistance with the functionality of standard hollow metal products. Our entire range of blast resistant products are readily available complete with builders hardware that provides an easy-to-operate door system.
Full engineering capability to design and manufacture blast products to meet the safety requirements of the end-user. Testing of units by independent laboratories complies with the most up to date test standards on the continent. Fire labelled products have been tested in accordance with NFPA-80 and are certified by Underwriters Laboratories and Warnock Hersey International. Blast resistant doors are available with glazing that is factory pre-installed.
Blast Resistant Doors & Frames for US Military Projects
The DoD Minimum Antiterrorism Standards for Buildings is designed to protect DoD personnel from terrorist attacks. Whether retrofitting an existing building or building a new one there are minimum blast pressure requirements that all door assemblies must meet. The specific requirements depend on building location, type, and occupancy. The October 1, 2013 version of UFC 4-010-01 makes it clear that unless a door failure in response to the applied blast load does not pose a risk to occupants (i.e. the door is intercepted by a suitably strong wall before entering an occupied area) all doors must be evaluated for blast resistance at the applicable charge weights & standoff distances.
Blast Resistant Doors & Frames for Industrial Projects
The petrochemical industry invests heavily in designing process plants to minimize the likelihood of accidental explosions. Although the probability of an accidental explosion is very low all buildings located within the range of accidental explosions are designed to be blast resistant. Other common industrial applications are flammable and/or pressurized materials storage and handling, paint booths, and ETO sterilization for medical and pharmaceutical products.
For further details on our industry-leading product and service, please communicate with us at your earliest opportunity.
What is a blast resistant door and frame assembly?
AMBICO offers pressure resistant openings in a wide variety of configurations that can withstand static pressure load ranging from 50 pounds per square foot (psf) to more than 100 pounds per square inch (psi) and are independently tested in accordance with the ASTM E-330 test standard or engineered in accordance with the most appropriate industry standards and guidelines. In addition, AMBICO offers blast resistant openings in a wide variety of configurations that are tested in accordance with ASTM F-2927 or ASTM F2247 for a variety of applications ranging from government or military applications subject to the Minimum Antiterrorism Standard for Buildings UFC-4-010-01, petrochemical or industrial applications meeting ASCE, PIP, ASTM, or CSA standards.
What do the terms seated and unseated mean? The term seated and unseated refer to the orientation of the opening swing as it related to the blast or shock wave. In the seated position, the blast is forcing the door against the frame soffit and stops whereas in the unseated position the blast is forcing the door away from the frame and the hardware is required to support the blast load.
What is meant by the term “rebound pressure” and how does it affect the blast resistant product that is specified?
Blast events are defined by two distinct phases – an initial “positive” phase where the full amount of the explosive pressure specified is loaded onto the assembly and a secondary “negative” phase where the pressure dissipates below the ambient pressure creating force in the opposite direction which is known as “rebound”. The additional contributing factor to the rebound force is through the “spring” effect of the door panel. The peak positive pressure load will cause the door panel to deflect. When deflection occurs but does not pass the yield point where deflection is permanent, the door will spring back during the rapid dissipation of pressure from peak pressure through to the negative phase. This “bounce back” also contributes to rebound force. The extent of the pressure during the rebound phase can be expressed as a percentage of the initial blast pressure. This figure ranges from zero percent to one hundred percent. This also is commonly expressed as true rebound, where the rebound affect is determined based on the door construction and stiffness.
What other blast information is required? In addition to seated or unseated and the peak applied pressure, it is also necessary to define the blast duration (i.e. how long does the peak pressure take to decay back to ambient pressure) measured in milliseconds (ms) or the blast impulse (i.e. the measure of blast energy represented by the area under the peak pressure versus duration triangle of the positive phase of the blast) measured in pounds per square inch per millisecond (psi/ms). Additionally, the mitigation or performance level required after the blast must be defined. In both the UFC-4-010-01 and the ASTM F2927 documents there are four levels of protection offered.
Why must the factory supply the door hardware complete with blast resistant doors?
When blast pressures occur in the unseated direction, the hinges and latch bolts are subjected to blast loads. Door hardware has been specifically designed and tested to form an integral part of AMBICO blast resistant units to resist blast loads in the unseated direction. Therefore, in these circumstances it is critical that the hinge and latching hardware be supplied by the door manufacturer as part of their certified blast resistant frame, door and hardware assembly.
