Additional_Q.docx

Additional Q&A Blast resistance, impact resistance, and wind load requirements of Aluminum Windows, Hollow Metal Doors, and Overhead Coiling Doors:

Section 085113/2.1 Performance Requirements of Aluminum Windows does not list blast or impact resistance requirement. But Section 085113/2.2-E requires "Blast Resistant Insulating-Glass Units at exterior window: ASTM E 2190 with two lites and complying with impact-resistance requirements in "Window Performance Requirements" Article."

Question 1: Are windows required to be blast and impact resistant? If so, does that requirement apply to the entire window assembly (including frame)?

Or only to the glazing?

There is no specification for the hollow metal doors, and Section 083323/2.2 PERFORMANCE REQUIREMENTS for Overhead Coiling Doors does not mention of blast or impact resistance.

Question 2: If windows are required to be blast and impact resistant, are hollow metal doors and/or overhead coiling doors to be blast and/or impact resistant as well?

The design wind load for Aluminum Windows is indirectly given by Section 085113/2.1-B which requires AAMA Performance Class CW, Grade 30 which would indicate a design pressure of 30 PSF. The design wind load for Overhead Coiling Doors only states 083323/2.2-A.1 "Design Wind Load: As indicated on Structural Drawings". Wind Design Criteria given on S1.0 would calculate to approximately 18 PSF wind load.

Section 083323/2.3-A.2 states that the Basis of Design door is Cornell Model EPI 1024. The Specifications for that door (found here at http://www.cooksondoor.com/products/cycle-master-high-speed-high-cycle-doors .html <http://www.cooksondoor.com/products/cycle-master-high-speed-high-cycle-door s.html> ) will withstand a 20 PSF maximum wind load, but is operational up to only 10 PSF. I called the engineering department at Cookson (manufacturer of the Cornell EPI 1024 door specified), and verified that they can not make a overhead coiling door to operate at 20 PSF. Ten PSF is the maximum. Section 083323/2.2-A.4 states that "overhead coiling doors to remain operable under design wind load, acting inward and outward." Thus there would appear there is a conflict in the specifications. The Basis of Design door can not meet the requirement to be operational at the required wind load.

Question 3: Given the apparent conflict in the specifications, is the basis of design door acceptable? Or must we install a door which can meet the requirement to be operational at maximum wind load given in structural?

Answer:

blast resistance for windows and doors at the Commercial Vehicle Inspection Station: The civil engineers, TD&H, determined that there was not a requirement for blast resistance due to perimeter proximity but in the Type B review MAFB said they wanted the exterior window to be blast resistant anyway. The glass in this window is required to be insulated with the outer pane of glass tempered and the inner pane of glass tempered and laminated. There is also a requirement for 1" glass bite in the frame. This information is called out in the specifications. There is no requirement that I know of for anything special for the exterior doors or overhead doors.