Document 71NRzkRm2X09wNEapq3QEE9bB

'i C Chemical Management Resources, Inc. P _ __ .63, G'cn Rock.-NfOTZofiTel (201) 447-9573 (M October 20, 1992 To: Pipe Resource Organization (PRO) RE: Article on PVC Piping.._in ICBQ_Journal The enclosed article " Is PVC Piping Firesafe?" appeared in the September-October 1992 issue of Building Standards,the ICBO bi monthly journal and was sent to me by the author. Dr. Joseph B. Zicherman. It is for your information and files. cc: Pat Benkner Bob Burnett CTL006983 Is PVC Piping Firesafe? by Joseph B. Zicherman, Ph.D. President Integrated Fire and Failure Technologies, Inc. Berkeley, California Dr. Zicherman is the president of Integrated Fire and Failure Technologies, Inc. (IFT, Inc.) Technical Services, Inc., Berkeley, California, where his consulting focuses on the performance of building products in the areas of firesafety and in-service durability. He has been active in the ICBO code development process and has worked extensively on the recent code changes to the Uniform Building CodeTM (U.B.C.), including adoption of the American Society for Testing and Materials (ASTM) E 814 tandard. Fire Test Method for Through-Penetration Firestops s U.B.C. Standard No. 43-6. Dr. Zicherman and IFT, Inc., have developed manuals on the use of various products as components in fire-resistive assemblies, and he is developing software to assist in product selection and specification processes. Dr. Zicherman's professional experience also includes teaching, writing for publication and directing product development programs. Because polyvinyl chloride (PVC) is an organic polymer, there are frequent fi resafety questions about its use as piping in fire-resis tive construction. What measures must be taken to ensure the in tegrity of fire-resistive assemblies penetrated by PVC piping or of assemblies containing PVC piping in wall cavities or floor/ceiling spaces? What is the firesafety record of PVC piping used in plumb ing applications? Answers to these questions lie in a review of testing and research results, performance in the field, and applicable codes and stand ards.' Historical Review The performance of PVC pipe was originally evaluated in exten sive ASTM E 119 fire-endurance test programs conducted in the early 1970s at the National Institute of Standards and Technology's (NIST) Center for Fire Research (CFR), at Ohio State University, and at the University of California at Berkeley.2 These programs were designed to determine whether fire-resistive wall assemblies whose cavities contained plastic drain, waste and vent (DWV) pip ing and whose membranes had been penetrated by fixture connec tions could maintain their fire ratings. The test results showed that, depending on how the pipe was installed, the piping would not re duce the fire ratings of such walls. American Society for Testing and Materials E 119 was used in these programs because it was the only test method available to as sess uniformly the performance of such elements as plastic pipe that entered, exited or went all the way through--that is, "through penetrated"--a test assembly at the time the fire-endurance per formance of assemblies containing plastic pipe became important to regulators. However, ASTM E 119 was not a perfect test method. It required a specimen no smaller than 100 square feet, but it did not provide specifics on instrumentation or specimen configura tion. Nor were there any criteria defining the atmospheric pres sures applied to specimens in the test furnace. Overlaying this situ ation, which contributed to variability in testing methods, was the large number of fire-resistive assemblies the codes accepted, none of which had ever been tested with piping installations of metal or plastic. These factors, as well as the large number of plumbing system configurations and combinations possible, made it necessary to 'The specific products considered here include PVC drain, waste and vent piping; CPVC (chlorinated polyvinyl chloride) domestic hot or | cold water piping; and CPVC sprinkler piping. Chlorinated polyvinyl f Reprinted from the November/December 1990 issue of Fire Journal, chloride is derived from PVC. None of these products includes plasti- National Fire Protection Association, Quincy, Massachusetts. cizing additives. They are based on unplasticized PVC, which is re- The views expressedhere are those ofthe authorand do not necessarily ferred to in Europe as "UPVC." reflea the opinion or agreement ofthe International Conference ofBuild- 2See also NFPA 251, StandardMethods ofFire Tests ofBuilding Construc- ing Officials. lion and Materials. CTL006984 i- RI/liniMr <TA WnA&nS/SonlomKor.rVtntwr 1992 select and test the most basic plumbing wall designs available. The designs chosen were based on certain considerations. Among these \\ as the tact that the most commonly used and most economi cal plumbing wall is the wood-stud cavity wall or minimum depth faced with gvpsum wallboard. The DWV system is a more vulner able plastic piping svstem than supply piping because it uses larger pipe sizes, the pipe is empty most ot the time, the system is \ ented Polyvinyl chloride piping was tested using ASTM E 814, Fire Test Method for Through-Penetration Firestops. The piping was installed in a fire-resistive wall assembly whose fire rating had been previously established in full-scale ASTM E 119 tests. Figure No. 1--Fire-endurance Testing of PVC pipe products, ASTM E 814 test preparation (before). BUILDING STANDARDS/Seplember-October. ll)9Z and includes stacks, and the connections must penetrate wall membranes at various locations. From a firesafety standpoint, the worst penetrations for DWV piping are back-to-back penetrations for trap connections Single-side trap connections and pipe stacks or branches that are within a cavity wall, but have no trap connec tions, are less critical. With these parameters in mind, each of the initial ASTM E 119 test series approached the problem from a different perspective. The CFR series, which was the most extensive, assessed the per formance of PVC pipe on a side-by-side basis with cast iron, copper and acrylonitrile-butadiene-styrene (ABS) plastic pipe systems. This series evaluated walls as narrow as those based on 2- by 4-inch wood framing and as deep as double-stud walls on wide plates, which are commonly found as party walls in townhouse-style con struction. Test configurations also included various plumbing chase designs and a metal stud wall. The CFR tests provided information on the base-line perform ance of the materials in various framing and piping configurations. The tests also demonstrated the importance of clearance between elements of PVC piping that penetrate gypsum wallboard and the importance of preventing stresses on wallboard, especially those which could be caused by fittings at through penetrations, over sized pipe and fitting contact. Installation methods, which in cluded metal sleeving for plastic pipes, were also tested. The Ohio State University tests evaluated relatively standard ASTM E 119 test wall assemblies without attempting to account for vertical fire spread to simulated upper or lower floors. Grout was used as the firestopping material where plumbing traps connected to waste and vent stacks. One- and two-hour-rated designs of 2- by 4-inch and 2- by 6-inch wood-frame walls with PVC DWV pipes were successfully tested for both fire endurance and hose stream resistance. The University of California series tested one-hour-rated, 2- by 6-inch wood-frame test walls with simulated floors above and be low a fire floor. Two tested methods were successfully used to fire-stop locations where PVC traps penetrated gypsum wallboard: Either 16-gauge sheet metal heat shields were installed to protect the penetration area or fiberglass batt insulation was placed in the piped stud cavity to a height of 48 inches. These three test series revealed the importance of installation methods which included the use of grout, metal sleeves, heat shields and thermal insulation. Installation detailing, which pre vented pipe and fittings from pressing against gypsum wallboard membranes, was shown to help performance and to prevent the formation of openings that might lead to premature burn-through. Penetration diameters could not be oversized, and annular spaces had to be sealed with the appropriate materials. Nor could open ings in plates be oversized unless they were filled with firestopping materials.3 New Test Method Adopted In 1981, the adoption of ASTM E 814, Fire Test Method for Through-Penetration Firestops, provided a needed methodology for testing items penetrating fire-resistive assemblies. It was devel oped to define instrumentation, appropriate specimen sizes and configurations to evaluate through penetrations of an assembly whose fire rating had been previously established in full-scale ASTM E 119 format. American Society for Testing and Materials E 814 uses the ASTM E 119 time-temperature curve, but it allows 3This is consistent with good practice, since oversized openings at plates or other penetration locations for any penetrating elements, plastic or otherwise, run counter to building code regulations that are designed to prevent spread of fire and smoke from compartment to compartment. Each of the model codes contains language to this effect. CTL006985 13 TABLE NO. 1--FIRE ENDURANCE TESTING OF PVC PIPE PRODUCTS Construction CAVITY WALLS AND PARTITIONS Bearing and nonload-bearing gypsum-clad assemblies with wood or steel studs, minimum frame 2- by 4-inch nominal; tests have included plumbing chases to 20 square inches CAVITY FLOOR'CEILINGS Wood- and metal-framed assemblies with 10-inch nominal joist systems with gypsum wallboard lower membrane and plywood or concrete upper surfaces SOLID CONCRETE SLAB MASONRY WALLS AND FLOOR'CEILINGS Thickness ranges from 4- to 8-inch details PVC piping systems tested 1 V2-inch laterals with maximum 4-inch vertical DWV pipe, with generic firestopping approaches; maximum 6-inch throughpenetrating elements tested with proprietary approaches tested Maximum through-penetration size Maximum opening size tested of of 4 inches 12 inches ASTM E 119 and ASTM E 814 fire One and two hours ratings achieved Two hours Two and three hours Summary of test conducted Twelve using generic firestopping approaches; four using proprietary approaches Two using proprietary firestopping Seven using proprietary firestopping1 'These are included as examples. Substantially greater numbers of assemblies have been tested with proprietary systems than are presented here. for smaller specimens, since the test assembly need only be repre sentative; from a practical standpoint, this means having sufficient clearances between the edge of the specimen, the test furnace and the fire stop itself. This does not preclude using ASTM E 814 with large specimens such as those required for ASTM E 119, evaluating multiple penetrations or assessing other firesafety aspects of an as sembly while assessing the integrity of the through penetration. The ASTM E 814 method has proven useful in developing new roducts because it provides a specific test method for regulators concerned with through-penetration integrity. It has proven espe cially appropriate for evaluating straight through penetrations, such as those made for sprinkler piping, supply piping, and ele ments of other mechanical or electrical systems. American Society for Testing and Materials E 814 has been adopted by all three United States model code organizations and is referenced in the Council of American Building Officials' (CABO) guidelines dealing with ducts, shafts, and pipe and cable penetrations. A similar stand ard was developed by Underwriters Laboratories (UL) as UL 1479. In contrast to generic plumbing elements installed in cavity walls, which typically are subjected to tests under ASTM E 119 or ASTM E 814 with ASTM E 119-sized specimens, most of the listed and labeled proprietary penetration firestopping systems and de vices deal with straight through penetrations of monolithic assem blies, such as slabs or walls. They are not generally applicable to plumbing wall penetrations of gypsum wallboard membranes, though exceptions do exist. While few technical articles referring to the fire performance of PVC pipe were published in the 1980s, third-party laboratories and listing agencies conducted numerous ASTM E 119 and ASTM E 814 tests during that period. The outcome of these tests reflect a matura tion of industrial technology and constitute a substantial database. Table No. 1 summarizes such fire-endurance test results on PVC pipe products with generic and proprietary firestopping systems, conducted by both public and private testing agencies under the ASTM E 119, ASTM E 814 and UL 1479 test protocols. More recently published were the findings of an independent dy conducted over the past several years to evaluate the firesafeof plastic piping products. As part of an environmental impact report for the State of California's Department of Housing and Com munity Development, the study examined the appropriateness of revising the state plumbing code to allow expanded use of plastic pipe. These findings indicate that PVC piping products are safe for use in fire-rated buildings, provided compartmentation is main tained (SRI 1983,1989). The report recommends appropriate con struction techniques and through-penetration firestopping meth ods to achieve this and stresses effective enforcement of applicable codes and standards. Fire Endurance of PVC Pipe Once flashover has occurred in a building plumbed with PVC pipe, what can be expected to happen? And what have we learned from fire-endurance testing of these products over the past 20 years? The ASTM E 119 test models a conservative, postflashover struc tural fire. In such a situation, most heat transfer within the space af fected by the fire is by radiation and re-radiation, as opposed to conduction through building elements, or by convection, as through the movement of hot gases (Kanury and Holve 1988). From a practical standpoint, PVC pipe found in cavity walls is strongly affected by this balance of heat transfer modes because increased temperatures cause PVC pipe to soften, sag and eventually fall to the bottom of a stud cavity or plumbing chase well before the gyp sum wallboard protecting the cavity falls away. This results in mini mal exposure of the pipe to direct thermal radiation. For example, wallboard fall off does not typically occur in a two-hour ASTM E 119 fire exposure of an assembly that consists of two layers of 5/8-inch gypsum wallboard on each side of metal or wood studs. As a result, the cavity heats up far more slowly than the fire compartment because it is shielded by the wallboard. Polyvinyl chloride pipe within such a stud cavity will soften, melt and drop to the bottom of the cavity in the first hour of the test. Rather than being distributed throughout the height of the wall, the pipe is thus found as a charred mass at the bottom ofthe stud cavity when interi or temperatures there begin to approximate furnace temperatures. This observation has been borne out by examination of hose-stream specimens, whose exposure duration is half the rating of a test wall, where PVC stack materials are found at the bottom of plumbing chases. How does PVC piping in a wall cavity or passing through a wall affect the fire performance of the rated assembly? The fire endur ance of rated assemblies built with steel or wood framing; gypsum wallboard; and concrete-and-masonry walls, floor slabs and floor/ ceilings are well characterized from a regulatory standpoint. Ex amples of many wall, floor, and floor/ceiling designs that have 14 CTL006986 BUILDING STANDARDS/September-October, 1992 one-, two-, or three-hour fire ratings are found in the model codes, in Ul's Fire Resistance Directory, and in the Fire Resistance Design Manual published by the Gypsum Association. One of the reasons the concept of generic, fire-rated assemblies is so widely accepted is that such designs have been tested repeatedly through the years under the ASTM E 119 method in similar, generally accepted con figurations. However, an almost unlimited variety of assemblies may exist when plumbing is installed in the field. For example, a wall is the most common type of fire-rated assembly used with plumbing sys tems. It may include a simple through penetration, as for sprinkler piping; various configurations of pipe without penetrations, as for runs of drain and vent pipe; or a single penetration, as for a single sink, often called a "membrane penetration." Back-to-back pene trations, such as those that occur in certain fire-rated, multiple-unit dwellings and include vertical runs of DWV pipe, are perhaps the most common, most critical configurations from a firesafety stand point. In principle, a wall assembly penetrated by any material is more prone to failure than the same assembly without penetrations. This is because openings or disruptions in protective membranes such as gypsum wallboard cause stress that is absent from unpenetrated assemblies. For wall assemblies, the most stressful situations in clude DWV lines running vertically within the wall and through penetrations, as opposed to membrane penetrations of only one side. For this reason, satisfactory fire test results from wall assem blies with vertical pipe runs and a through penetration provide the "worst-case" fire test scenario. Assemblies in which PVC piping materials run within cavities but do not through-penetrate the wall or penetrate just one side of the wall are less stressed and thus less prone to failure than the designs incorporating both through pene trations and vertical runs of PVC drain and vent piping. In the past, concern has been raised about the use of exposed PVC pipe in areas such as parking garages and the basements of fire-resistive buildings. Since such buildings incorporate compartmentation, the boundaries of the fire-resistive construction enve lope are required to prevent fire spread, and they are designed ac cordingly. If through penetrations are properly protected, fire spread from affected compartments is thus mitigated. In addition, PVC pipe will not ignite readily before flashover because it con tains chlorine, which provides built-in resistance to ignition and does not contain plasticizers, which would reduce that resistance. After flashover, the exposed PVC piping will contribute to the fire and smoke developed, along with any other combustibles in the af fected compartment. Firestopping Approaches and Systems for PVC Pipe Firestopping for PVC piping systems falls into two categories. The first involves generic, passive approaches and nonproprietary ma terials such as grout, thermal insulation, and other filling or back packing materials at penetration locations. These methods have been demonstrated in ASTM E 119 tests on cavity walls with DWV stack-and-trap connections. This approach has been success ful for various one- and two-hour-rated plumbing wall assemblies, provided construction detailing was performed reasonably. The most typical of these methods uses nonshrinking grouts or com monly available fiberglass batt insulation to prevent fire spread. The second approach to firestopping PVC through penetrations of fire-rated walls, slabs or assemblies involves the use of propri etary firestopping products. Most of these products are specialized mastics, insulations or thermally activated systems based either on mechanical closure of openings or chemical closure achieved BUILDING STANDARDS/September-October, 1992 through intumescent technology.4 These systems rely on the fact that, during a tire exposure, PVC pipe becomes soft before igniting Thus, an appropriate intumescent material will close and seal an opening containing such a pipe before fire can spread. Successful one-, two-, and three-hour fire tests have been con ducted with intumescent systems for openings in masonry walls up to 12 inches in diameter under positive-pressure fire test conditions (UL 1988).Tested and listed thermally activated mechanical fire stopping devices include those that can plug a pipe at a through penetration or cut through a plastic piping assembly and seal it with a guillotine-like device to prevent fire spread when elevated tem peratures occur. Recent Research Since the early 1980s, research into PVC piping firesafety has fo cused on two areas. The first is proprietary systems for firestopping that requires extended fire endurance or involves larger openings and pipe sizes and larger numbers of penetrating elements. These efforts have led to the development of specific systems and asso ciated installation methodologies to protect such openings, and to listing with approved third-party agencies. In most cases, the re search committee of one or more of the model code organizations has also reviewed the performance of these products. The second area of research involves development of generic firestopping systems for metal-framed walls similar to those dem onstrated in the 1970s for one- and two-hour-rated wood-frame walls. In a recent test series conducted with generic firestopping based on grout or fiberglass batt insulation, PVC DWV stack sys tems with through-penetrating 1 V;-inch laterals and traps were in stalled in one- and two-hour noncombustible steel-stud wall as semblies faced with gvpsum wallboard. The tests were conducted under positive pressure, as called for in the codes for ASTM E 814 testing. Both small- and large-scale assemblies--that is, 4- by 5-t'oot and 10- by 12-foot assemblies--were tested so that correla tions between the former, which are most typically used in ASTM E 814 tests, and the latter, required for ASTM E 119 testing, could be observed. In the latter, instrumentation of through penetrations was conducted according to the ASTM E 814 standard, and test specimens included vertical penetration of concrete inserts that simulated slabs at the top and bottom of exposed sections of test wails (see Figures Nos. 1 and 2). Post-test photos of such penetra tions show no vertical fire spread beyond the tested area (Warnock Hersey 1989a and 1989b). These tests confirm that generic firestopping approaches for PVC pipe perform as satisfactorily with steel-frame assemblies as they did with the wood-stud wall assemblies tested earlier by NIST's Center for Fire Research, Ohio State University and the University of California at Berkeley. Pressure Effects on Fires Involving PVC Pipe During a postflashover fire, there are pressure gradients that in crease from negative values in the range of -0.02 to -0.01 inch of water at floor level to zero at about one third the height of the af fected room. These pressures continue to increase so that, near the ceiling, positive pressure may be in the range of +0.02 to +0.04 inch of water (Fang 1984). The effect of such pressure gradients on fire travel through as semblies that include penetrations has been debated extensively in code forums, where the pressures in test furnaces have been an is sue. In response, each model code organization has stipulated that positive pressure be applied to assemblies tested under ASTM E 814. This is a conservative assessment, however, since a fire-resis tive assembly is most commonly penetrated by a pipe at a sink. `intumescent materials are those which are engineered to expand during a fire and create an insulating char barrier. CTL006987 15 I l f "which will be under negative pressure during a postflashover fire. Yet such pressure requirements are appropriate in testing, since piping may also pass through fire-resistive assemblies high in a room, as at floor penetrations or above a hung ceiling. Sprinkler piping, for example, is usually run overhead, as is domestic hot and cold water piping.5 Water Distribution Piping Because the cooling effect of the water contained in both chlori nated polyvinyl chloride sprinkler systems and domestic hot and cold water systems prevents ignition and because the additional chlorine atom on the CPVC molecule enhances its fire perform ance compared to the usual PVC piping materials, generic firestop ping approaches are appropriate for these systems. For openings with a diameter greater than 2 inches, devices and proprietary sys tems that have been tested with PVC or CPVC in these size ranges should be used as required by the codes. Listings for CPVC-based fire sprinkler systems were obtained af ter fire tests that included both direct and indirect exposure of sprin kler piping and fittings to fire conditions. These included ambient exposures with temperatures up 1 ,700F. from burning wood cribs secondarily fueled with heptane. Various types of sprinklers were evaluated with the CPVC systems, and listings for both light and or dinary occupancies, as well as residential use under NFPA 13D, Standard for Sprinkler Systems in One- and Two-Family Dwellings and Mobile Homes, have been issued (UL 1985; Wilging 1988). Codes and Standards In the 1980s, the plastic pipe industry increased its efforts to make systematic installation information available to code offi cials, specifiers and engineers wanting to use PVC piping products *n fire-resistive construction. These efforts included publication of the installation manual. Plastic Pipe in Fire Resistive Construction*, which addressed questions of installation detailing, materials to use and which classes of fire-resistive assemblies had undergone testing according to ASTM E 119, ASTM E 814 or both. An updated edition of that document has been published in collaboration with the National Evaluation Service of CABO. While few changes affecting the use of PVC pipe and fire-resis tive construction were made in the 1982,1985 and 1988 editions ofthe Uniform Building Code, the 1991 U.B.C. includes substantial changes to Chapters 1 7 and 43, which directly affect PVC pipe products as well as other plastic pipe, tube and conduit products. Along with these changes to U.B.C. Sections 1706 and 4301 through 4308, U.B.C. Standard No. 43-6 has been added. This standard is based on ASTM E 814, with appropriate provisions for measurement of test pressure so that the U.B.C. requirement for positive pressure is satisfied. This standard will augment U.B.C. Standard No. 43-1 for the full-scale testing of walls and floor/ ceiling assemblies containing PVC piping products. At this time there are no restrictions in the U.B.C. on the use of PVC plastic pipe products in buildings of all construction types. For use of PVC piping in concealed spaces, however, reference is made to sections of the Uniform Mechanical CodeTM which relate to plenums and the use of combustibles in concealed places. In all interestingly, the building code in Canada calls for positive-pressure test ing to be conducted at a level 10 times that called for in the United States. The justification for this is, in part, based on "stack effect' argu ments. One can question the requirement for such high-pressure differ entials at tests based on the presence of engineered smoke-control pres surization systems in high-rise buildings constructed today. Such build ings in the United States are also required to incorporate fire-resistive construction and sprinkler systems. Conversely, the stack effect is not a factor in low-rise, fire-resistive buildings. `This manual is available from the Plastic Pipe and Fittings Association, Clen Ellyn, Illinois. 16 The results of the ASTM E 814 fire endurance test of PVC piping in a fire-resistive assembly are evident in these two photos taken after the test was completed. Figure No. 2--Fire-endurance testing of PVC pipe products, ASTM E 814 test results (after). CTL006988 BUILDIN'C STANDARDS/Sepk'mhfr-Ociolxrr. 14(J2 I ! i cases, PVC pipe should not be exposed in plenums having an air handling function without protection. The 1 983 Uniform Plumbing Coc/eTM (U.P.C. ) restricted use of PVC drain waste and vent pip ing to buildings of "combustible construction." The 1991 U.P.C. abolishes the combustible construction clause, but--unlike the other model plumbing codes in the United States--will restrict use of PVC drain waste and vent piping to structures three stories or less in height. Field Data on Fire Performance Polyvinyl chloride plastic piping has been used widely in the United States for drains, waste removal, vents, roof drains, chilled water, and low'-temperature heating and cooling in nont'ire-rated construction for over two decades. The firesafely record for these materials and the fire test results discussed above have been largely responsible for their increased use in more restrictive construction applications. In addition, the sections on alternate materials and methods in each of the model codes have permitted installation of PVC drain, waste removal and vent piping in fire-rated construction for some years. These include multiple-unit, fire-resistive structures, includ ing high rises. In those projects, no evidence of a fire-related prod uct defect or failure has been reported or has been the subject of a product liability action. The latter is a good barometer of PVC pip ing fire performance, given the litigious climate in which we work and live. Rarely have products used in fire-resistive construction been subjected to as extensive an evaluation as PVC-based piping prod ucts. They have been the subject of fire-endurance testing at both publicly and privately funded laboratories on numerous occasions and in a variety of configurations, and this test work has been fur ther evaluated by third parties involved in the regulatory process at local, state, regional and federal levels. The results of this testing and evaluation, as well as many years of field use, indicate that properly installed PVC-based piping products do not constitute a fire hazard in structures. BIBLIOGRAPHY Fang, J. B.(1984). Static Pressures Produced by Room Fires, NBSIR 80-1984. National Bureau of Standards, Center for Fire Research. Kanury, A. M. and D.). Holve (1988). A Theoretical Analysis of the ASTM E 119 Standard Fire Test Building Construction Materials, NBS-GCR 76-50. United States Department of Commerce, National Bureau of Standards. SRI (Menlo Park) (1983). Plastic Plumbing Pipe. Draft Environmental Impact Report. State of California Department of Housing and Community De velopment. Draft I. SRI (Menlo Park) (1989). Plastic Plumbing Pipe. Draft Environmental Impact Report. State of California Department of Housing and Community De velopment. Draft II, August. Underwriters Laboratories (1985). Report on CPVC Pipe and Fittings for Sprinkler Systems. File Ex3754/Project 85NK837. Underwriters Labora tories, Northbrook, Illinois. July 17. Underwriters Laboratories (1988). Building Materials Directory. Underwrit ers Laboratories, Northbrook, Illinois. January. Warnock Hersey International, Inc. (1989a). Report on the fire endurance and hose stream tests of PVC plastic pipe penetrations through a 7'/4-inch-thick, 1-hour rated gypsumboard and steel stud wall. Fire Per formance of PVC Pipe in Non-Combustible Construction, Files WHI-495-PSV-0580 and WHI-495-PSV-0635. Pittsburg, California. Jan uary. Warnock Hersey International, Inc. (1989b). Report on the fire endurance and hose stream tests of PVC plastic pipe penetrations through an 8'/2-inch-thick, 2-hour rated gypsumboard and steel stud wall. Fire Per formance of PVC Pipe in Non-Combustible Construction, Files WHI-495-PSV-0580 and WHI-495-PSV-0635. Pittsburg, California. Jan uary. Wilging, R. C. (1988). Plastic fire sprinkler piping 1967-1987. The Building Official and Code Administrator. July/August. Uniform Mechanical Code Application/Interpretation Manual mi-- Q: A: Anplicalion/liitefpretatlim Manual The new U.M.C. Application/Interpretation Manual amplifies the intent of the code provisions and enhances the Mechanical Code user's ability to apply the code effectively. Quoted sections from the 1991 edition of the Uniform Mechanical CodeTM (U.M.C.) are followed by questions that might arise in the application of each section. Answers to those questions are accompanied by illustrative examples. The manual also provides a comprehensive analysis of the intent of the code section. The manual is written in the familiar format of the "Code Applications and Interpretations" section of Building StandardsTM magazine and comes in a loose-leaf binder so you can include future code interpretations published in the magazine. Update your reference library to include the U.M.C. Application/ Interpretation Manual, an especially valuable resource for building officials and their staff when applying the code to complex situations. ORDER NOW! CAR (310) 692-4226 or FAX (310) 692-3853 7D0 ajn.-5ttlp.nl. ICBO Members Nonmembers Item No. 122L91 $20.00 $25.00 BUILDING STANDARDS/September-October, 1992 CTL006989 17