In the May 2014 issue of The Construction Specifier, we published the article, “Passive Fire Protection and Interior Wall Assemblies,” by Gregg Stahl. Soon after, a reader contacted us regarding what he considered inaccuracies. We reached out to the author and, in the interest of continuing the discourse about this important topic, excerpts from both sides are included below.
Reader: The first issue is the reference to ASTM E603. The author mentions this is one of two standards that rates assemblies. Actually, ASTM E603 is a “guide” standard, and is used to explain the various types of fire tests, whether they are ASTM, NFPA, UL, or FM, and how they can be compared and contrasted. This standard is not a test method.
Author: The reader brings up several good points in regard to the article on passive fire protection. It should be noted, however, this piece was intended to provide a general overview on the basic principles of passive fire protection. As to the first point, the reader is technically correct. E603 is in fact an ASTM “Guide,” not an ASTM “Standard.” In the “Scope” section of this guide, it does state one of the purposes is to “allow(s) users to obtain fire-test-response characteristics of materials, products, or assemblies, which are useful data for describing or appraising their fire performance under actual fire conditions.” In the subsequent paragraphs, I go on to describe how A603 is used as well as differentiating it from the E119 fire test, which is testing the effectiveness of a particular assembly.
Reader: The second issue is the article states ASTM E119 tests the effectiveness of an assembly as a “fire barrier.” Although not untrue, the use of “fire barrier” seems to limit the type of fire-rated assembly that is tested, since a “fire barrier” is a specific type of fire-rated assembly used by the IBC and NFPA. ASTM E119 is used to test any type of assembly for fire-resistance, whether it is a wall, roof system, floor system, column, beam, etc.
Author: I should have been more precise in the selection of the terminology used. The intent of the term was to use a dictionary meaning, not a fire test assembly meaning. A Google search for the term will produce numerous definitions, such as the one below:
fire barrier: a continuous vertical or horizontal assembly, such as a wall or floor, that is designed and constructed with a specified fire resistance rating to limit the spread of fire and that also will restrict the movement of smoke. Such barriers might have protected openings.
Reader: The third issue is mentioning the hose stream test is used to “measure an assembly’s resistance to water pressure.” This is misleading. The hose stream test is not really a measure of an assembly’s resistance to water pressure, but to test the system’s integrity. As the commentary to the standard states, the hose stream tests the “ability of the construction to resist disintegration under adverse conditions.” In other words, it is a way of testing, from a distance (it is very hot) the assembly’s integrity from falling debris.
Author: The reader references “the standard,” but I do not know to which standard he is referring. ASTM E2226, Standard Practice for Application of Hose Stream, states:
1.3 – The result derived from this practice is one factor in assessing the integrity of building elements after fire exposure. The practice prescribes a standard hose stream exposure for comparing performance of building elements after fire exposure and evaluates various materials and construction techniques under common conditions.
The application of the hose stream does exert pressure on the assembly after it has completed either the full cycle of an E119 fire test or 50 percent of the time of the rated wall assembly. I agree the single word “pressure” does not go far enough to explain—the intent was to determine the integrity of the remaining assembly.
Reader: The fourth and final issue is the use of “area separation firewalls” in the article, and its associated endnote. The use of “area separation” walls was dropped when the IBC was published in 2000, and is not a term used by NFPA’s standards. The correct term used by both the IBC and NFPA is “fire wall” (not a single word). The endnote (no. 3) gives the impression these “area separation firewalls” are used to separate residential units or commercial tenants. This is incorrect. A fire wall divides a building—residential or commercial—into separate buildings so they can be considered independently when applying the code. “Fire partitions” are used for residential unit and commercial tenant separations within a single building and do not require the type of requirements described in the article.
Author: I respectfully disagree with the reader, who seems to be making the reference to area separation walls fit his use without recognizing the term can have more than one use or intent. It was employed here with no reference to NFPA or IBC, and was not intended as the reader interpreted it.
The term “area separation wall”—or “ASW” as it is commonly abbreviated—is used for a particular type of fire-rated wall assembly with a two-hour fire resistance rating, which is typically intended to permit controlled collapse of one unit in a multifamily residence, while still remaining intact and able to protect the adjacent unit in a fire situation. This is a common term in the construction industry. The reader can check the literature of various manufacturers and find this type of assembly. There are also various UL assemblies for this type of construction.