Field inspection and enforcement
While proper design and testing of perimeter fire barrier joints is critical, poor installation and maintenance can lead to unacceptable real-world performance in fires. To help alleviate this, ASTM E2393 was first published in 2004. This practice covers the procedures to inspect fire-resistive joint and perimeter fire barrier systems, including methods for field verification and inspection. This standard practice provides methods by which qualified inspectors verify required fire-resistive joint systems on a project have been installed in accordance with the inspection documents.
Adoption and use of ASTM E2393 has been growing across the United States in recent years. In fact, since the publication of the 2012 IBC, “special inspection” is required for perimeter fire barrier systems installed in high-rise buildings, or in buildings assigned to Risk Category III or IV. Special inspection includes monitoring of materials, installation, fabrication, erection, and placement of components and connections that both require special expertise and are critical to the integrity of the building structure. Special inspections are supplemental to the typical municipal inspections required by the building department specified in IBC. Special inspectors monitor the materials as well as the workmanship critical to the structural and fire-resistive integrity of a given building, and bring technical expertise to the job that is not typically available in local government.
IBC clearly identifies situations in which the employment of special inspectors or special inspection agencies is mandatory. In those cases, the use of special inspectors and special inspection agencies is not discretionary.
Conclusion
The importance of balanced fire protection cannot be sufficiently stressed. The fire death rate per 1000 fires and average loss per fire are generally lower in high-rise buildings than in other buildings of the same property use. This is because high-rises are more likely to have fire-resistive construction and wet pipe sprinklers.
Perimeter fire barrier systems are an important part of effective fire-resistance-rated and smoke-resistant compartmentation systems. They have been developed for fire and life safety protection at the important curtain wall gap.
Neglecting the curtain wall/floor void means compromising the safety of people in the building. When floors are required by codes to have a fire-resistance rating, this comes with a financial cost. Improper installation or design of perimeter joint protection not only compromises fire safety, but also negates some of the building fire protection performance for which owners are paying.
Mineral wool is suited to provide the necessary fire safety performance. Its high melting temperature, coupled with dimensional stability and high tensile strength, provides the resistance needed for these critical applications. Perimeter fire barrier systems provide designs capable of maintaining continuity of the fire-resistance-rated floor to the exterior edge of the building for both rated and nonrated exterior walls. This provides vertical compartmentation for the potentially large gap areas at the edge of floor slabs, to prevent fire from spreading vertically.
Ultimately, proper execution of perimeter fire barrier systems requires collaboration between architects, specifiers, general contractors, installers, and inspectors. They need to design it according to code, specify it correctly, critically evaluate substitutions, and then install it properly.
Tony Crimi, P.Eng., MASc., is a registered professional engineer and founder of A.C. Consulting Solutions Inc., specializing in building- and fire-related codes, standards, and product development activities in the United States, Canada, and Europe. Working with manufacturers and industry associations, he advocates for approval and safe use of materials and products, and for their code recognition. Crimi has more than three decades of experience in the area of codes, standards, testing, and conformity assessment. He is an active participant in International Code Council (ICC), National Fire Protection Association (NFPA), ASTM, UL, and ISO, and is the immediate past-chair of the National Building Code of Canada (NBC) Standing Committee on Fire Protection. Crimi can be reached at tcrimi@sympatico.ca.
