When testing a W-shaped column for SFRM thickness, the specified thickness is 1-7/16 inch. 2 of the measurements are 1-3/16 inch and 1-1/4 inch while the rest are above 1-7/16 inch. Is this acceptable?

• A. Yes, acceptance criteria is met
• B. No, not acceptable
• C. Only if the two below meet a revised criterion
• D. Only if more measurements exceed the spec

Answer: (A)

The key idea is how acceptance is determined for SFRM thickness: you don’t need every point to hit exactly the specified thickness, but you must meet the allowable tolerance pattern defined by the testing standard. In many field-testing schemes, a small number of readings below the exact thickness is permissible as long as the overall results meet the required criteria (for example, only a limited percentage of points may fall short, while readings at or above the specified thickness are acceptable).

Here, the specified thickness is 1-7/16 inch. Two measurements come in below that value (1-3/16 and 1-1/4), while the rest are at or above the specified thickness. Because the majority meet or exceed the target and the under-thickness readings are within the typical allowable limits, the installation would pass the acceptance criteria. If the number of readings below the spec or the shortfalls were larger than what the protocol allows, it would not be acceptable.