Stone Security Engineering authored a new GSA blast standard that was approved and released in August 2011: GSA Facility Security Requirements for Explosive Devices Applicable to Facility Security Levels III and IV. This document provides detailed criteria for implementing the blast and progressive collapse requirements of the ISC 2010 giving specific design and performance requirements for GSA facilities required to meet an FSL III or IV.
In general terms, the security measures implemented for both FSL III and FSL IV require a certain level of blast and progressive collapse hardening of the facility. In an FSL III facility, these security measures are, for the most part, prescriptive including while an FSL IV facility will need to meet more performance based requirements.
The document also provides updated guidance on balanced design for window systems, details of how to implement the modified standoff distance requirements in the 2010 ISC Physical Security Criteria (major change from the 2004 ISC Security Design Criteria), and detailed technical information to implement blast resistant design for GSA Level III and Level IV buildings.
This document is now being implemented on GSA and GSA related projects and it is important for project teams working and bidding on government work to understand the requirements.