How many thickness measurements are required for joist testing?

For joist testing, the requirement is to take a minimum of seven thickness measurements. This standard ensures that the measurements adequately represent the overall thickness of the spray-applied fireproofing, covering any variations that may occur due to application practices, surface conditions, or other factors. Collecting multiple measurements allows for a more accurate assessment of the fireproofing's consistency and effectiveness across the entire application area.

Taking fewer than seven measurements might not provide a complete picture and could potentially overlook critical inconsistencies that could affect the fire resistance performance. It's vital for ensuring compliance with fire safety standards and achieving the intended protection of structural elements.