What is the Impact Test and what is large and small-missile resistant?
The Miami-Dade Building Code requires that every exterior opening – residential or commercial – be provided with protection against wind-borne debris caused by hurricanes. Such protection could either be shutters or impact-resistant products. There are two types of impact-resistant products: large-missile resistant and small- missile resistant. A. Large-missile resistant A product exposed to various impacts with a piece of lumber weighing approximately 9 pounds, measuring 2″ x 4″ x 9’ in size, traveling at a speed of 50 feet per second (34 mph). Then the product is subjected to hurricane loading of 9,000 wind cycles, positive and negative. B. Small-missile resistant A product that has been exposed to various impacts with 10 ball bearings traveling at a speed of 80 feet per second (50 mph). The product is then subjected to wind loads for 9,000 cycles. If the doors and windows are more than 30 feet from the ground then they must be either large or small missile compliant.
