Explosive Weight I and Explosive Weight
II?
Question
Can you break me down the difference in Explosive Weight I and Explosive Weight II?
Answer
This is the criteria from the
2012 UFC:
Explosive weight I is associated
with a larger weight of TNT for a van or truck bomb outside of the base
perimeter. Its based on the assumption that a vehicle bomb will not
be able to penetrate the base perimeter and/or will be detected at the
gate. If we have a facility that is less than 200 feet from the base
perimeter/fence, then we must consider explosive weight I in addition to
explosive weight II and its pressure/impulse may govern over the explosive
weight II.
Explosive weight II is
associated with a smaller weight of TNT simulating a back-pack or smaller bomb
that gets past the base gate. The standoff for this explosive weight is
no longer the 82 feet typical of the 2007 criteria. Now it is based on
the new conventional stand-offs that are listed in the tables based on
construction type and load bearing/non-load bearing walls. The actual
stand-off must be used which is from the parking lot to the window/wall in question.
Hope this helps. Please
call if you have any questions.
Stewart P. Jeske, P.E.
JEI Structural - Glazing Systems
Engineering
