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Blast Design & Physical Security


The job of a blast design engineer is to understand the risk and consequences of an explosive event, and then to develop methods for reducing the potential harm caused to people and critical assets.

How can you be sure your building is protected and built with the latest standards in physical security?

A prevailing myth about the Physical Security design process is that a consultant can begin their involvement with the project after 35% design of the project is complete. This is too late though, as by this time, sites have been selected and laid out, and the building structural and envelope systems have already been selected.

Risk assessment forms the basis for physical security and bomb blast design. Assets should be categorized and prioritized, threats should be identified regarding aggressors and potential tactics, and you must be aware of any vulnerabilities that could be exploited by these aggressors.

How Does Blast Design Minimize Damage?

IEI routinely conducts peer reviews of both structural and physical security designs on behalf of the federal government. A fundamental concept used in blast design is the Conservation of Energy Principal – energy cannot be created or destroyed. However, a blast can hit a building and transfer its energy, much like a bowling ball knocking down pins.

Unified Facilities Criteria (UFC) 04-010-01 identifies 21 standards that must be considered for physical security and blast design.

These standards include but are not limited to: standoff distances, unobstructed space, access roads, parking conditions, progressive collapse, and structural isolation. Standoff distance refers to the intentionally designed physical distance or means by which protection is integrated into facilities, personnel, or any other type of asset from a potential threat.

The UFC defines Progressive Collapse as “The spread of an initial local failure from building element to building element, eventually resulting in the collapse of an entire structure or a disproportionately large part of it.” Progressive Collapse can be prevented by adding redundancy and local hardening to the structural design of the building.

UFC 4-010-01 aim to reduce collateral damages and the scope and severity of mass casualties in buildings in the event of a terrorist attack. It encourages the use of cost effective, implementable, and enforceable means of protecting personnel if such an attack were to happen.

UFC 04-010-01 identifies 21 standards that must be considered for physical security design. These standards include but are not limited to:

o Building overhangs and breezeways
o Exterior masonry walls
o Windows and skylights
o Building entrance layouts
o Exterior doors
o Standoff distances
o Unobstructed space
o Access roads
o Parking conditions
o Progressive collapse
o Structural isolation
o Mail rooms and loading docks
o Roof access
o Air intakes
o Ventilation shafts
o Equipment bracing
o Under-building access

Innovative Engineering Inc., Provides Blast Design Expertise

It is highly advantageous for the physical security consultant to assume Engineer of Record responsibilities. If this does not happen, you will often be left with a report of requirements by the consultant that have not been actually incorporated into the construction documents.

Innovative Engineering will be exhibiting at The Society of American Military Engineers (SAME) Small Business Conference this year at the Georgia World Congress Center! Come get your picture with Bigfoot!

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