Which of the following is NOT listed as a credited testing laboratory for firestopping?

The National Fire Protection Association (NFPA) is not listed as a credited testing laboratory for firestopping because its primary role focuses on developing codes and standards related to fire prevention and safety rather than conducting testing itself. NFPA establishes guidelines that organizations can follow to ensure safety standards in fire prevention, but it does not engage in the physical testing of materials or systems to determine their performance.

In contrast, the other entities mentioned, such as Underwriters Laboratories Inc., Omega Point Laboratories, and Internet Testing Services, are known for their involvement in testing and certifying firestop products and systems. These organizations have the technical expertise and facilities required to execute rigorous testing methods to evaluate the effectiveness of firestopping products, thereby ensuring they meet industry standards for safety and performance.

By understanding the unique roles of these organizations, it becomes clearer why NFPA stands apart as a standards-setting body rather than a testing laboratory for firestopping.