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ASTM Construction Standards in Laboratory Accreditation
by Patrick McCullen
ASTM construction standards are used around the world as referenced
in the International Building Code. Patrick McCullen, of the International
Conference of Building Officials Evaluation Service (ICBO ES),
describes just some of the many testing uses of ASTM standards
for building construction purposes.
The International Conference of Building Officials (ICBO) promulgates the Uniform Building Code, the International
Building Code and other model codes widely adopted in the United
States by code-enforcement agencies. ICBO is the largest organization
in the country representing building regulators. Complementing
the services it provides to the regulatory community, ICBO established
a subsidiary corporation, ICBO Evaluation Service, Inc. (ICBO
ES) in 1986. As a nonprofit, public-benefit corporation, ICBO
ES provides technical reports on building products, components,
methods of construction and materials recognized as complying
with building codes to the regulatory community. The technical
reports are based largely on tests from laboratories that are
accredited by ICBO ES under international standards. Operating
independently of the product evaluation program, ICBO ES provides
a laboratory accreditation program that accredits laboratories
to perform tests on building products and materials.
The ICBO ES laboratory accreditation program is recognized nationally
by the National Cooperation for Laboratory Accreditation (NACLA),
and is recognized internationally by the International Laboratory
Accreditation Cooperation (ILAC). The test reports from ICBO ES
accredited laboratories are accepted widely in Europe and in Asia-Pacific
economies. The ICBO ES program is one of only three in the United
States to be so widely recognized and endorsed.
Standards Are the Building Blocks
To be used in support of ICBO ES evaluation reports, conventional
building products (such as concrete, wood, masonry, steel, and
aluminum) and newer building materials and systems (such as carbon
fiber composites, foam plastics, and structural composite lumber)
must be tested and meet nationally recognized standards set forth
in the building codes and ICBO ES acceptance criteria.
Up until 1999, all three model code agencies in the United States
published their own proprietary codes, which included in some
instances proprietary test standards for the testing and acceptance
of building products. In 1994, the International Code Council
(ICC) was established and dedicated to developing a single, national
code. In 2000, the efforts of the ICC culminated in the publication
of the International Building Code (IBC), which places great emphasis
on the use of consensus test standards such as those published
by ASTM. Because of the IBC, the role of ASTM in the application
of building codes has increased, because of the number of ASTM
standards and test methods that are referenced in the IBC. Widespread
adoption of the IBC and its reference standards, coupled with
the dramatic increase in international trade, has heightened awareness
of the need for competent, internationally accredited testing
laboratories to test products and determine if they conform to
the specifications and performance criteria set forth in the ASTM
standards. The proliferation of new building materials and systems
that are qualified by performance testing emphasizes the importance
of the testing laboratory in qualifying construction materials.
Fire Resistance
Early in its program, ICBO ES focused much effort on the accreditation
and on-site assessment of construction materials laboratories
that conducted fire-resistance testing under ASTM standards referenced
in building codes. These standards, like many ASTM standards,
were written by the laboratory technicians and engineers who did
original fire-resistance research and development, and who also
built the actual equipment used in conducting the tests. Often,
the standards simply reflected the equipment and procedures that
evolved out of this research work. What began as an experiment
and evolved into a standardized procedure through the ASTM process,
often became law eventually, when the test method was adopted
into the building codes.
The accreditation of fire testing laboratories became a major
issue with ICBO ES when it was discovered in the late 1970s that
certain claims being made by manufacturers, based on tests conducted
at little-known laboratories, were suspect or inconsistent with
previously accepted data. When no plausible explanation of the
suspect test results could be found, it became necessary to examine
in detail the test methodologies and the laboratories that conducted
the tests.
ICBO ESs first approach was to enlist the services of experienced
fire testing experts to review test reports, visit laboratories
and interview laboratory staff. Although this approach brought
answers to some of the more obvious questions, it became apparent
that a more in-depth approach was needed to definitively resolve
test discrepancies. It was at this point that ICBO ES assessors
took a closer look at the ASTM test methods and developed detailed
checklists based on the standards themselves. Concentrating on
parameters in ASTM methods that were critical to ensuring reproducible
test results (and to ensuring that the tests were being conducted
as intended), the detailed checklists became valuable tools in
the hands of ICBO ES laboratory assessors, enabling them to conduct
effective technical assessments of laboratories. There are numerous
and critical thermal measurements, construction details, sample
conditioning and data acquisition requirements in medium- and large-scale fire-resistance
and flame spread tests, such as:
E 84, Test Method for Surface Burning Characteristics of Building
Materials;
E 108, Test Methods for Fire Tests of Roof Coverings;
E 119, Test Methods for Fire Tests of Building Construction and Materials;
E 152, Methods of Fire Tests of Door Assemblies (which was discontinued
in 1995); and
E 163, Methods for Fire Tests of Window Assemblies (also discontinued
in 1995).
If the requirements in the ASTM methods in these specific areas
are not strictly adhered to, large variations in test results
will result. This is one reason ICBO ES assessors now use detailed
technical checklists to facilitate the evaluation of a laboratorys
test methods, the suitability of its equipment, and the competence
of its staff.
Fire Research Project
One example of the effectiveness of this checklist approach was
demonstrated in an ASTM fire research project sponsored by the
ASTM Institute for Standards Research. Entitled Interlaboratory
Test Program to Validate the ASTM E 84 Test Method for Surface
Burning Characteristics of Building Materials, this interlaboratory
test program was conducted by ASTM Committee E05 on Fire Standards
and the International Organization for Standardization (ISO) Technical
Committee 92. The scope of the research project was to validate
the following ASTM standards and several ISO fire performance
tests:
E 84, Test Method for Surface Burning Characteristics of Building
Materials;
E 906, Test Method for Heat and Visible Smoke Release Rates for Materials
and Products;
E 1321, Test Method for Determining Material Ignition and Flame Spread
Properties;
E 1354, Test Method for Heat and Visible Smoke Release Rates for Materials
and Products Using an Oxygen Consumption Calorimeter; and
Proposed Method for Room Fire Test of Wall and Ceiling Materials
and Assemblies.
The objective of the project was to conduct a global interlaboratory
test program among volunteer laboratories that were willing to
evaluate the fire performance of six materials, utilizing one
of the above test methods. There were three goals for the project:
(1) to provide precision and accuracy data for each test method;
(2) to provide correlation data between the various fire tests
in use throughout the United States and Europe; and (3) to obtain
a further understanding of the ASTM fire test methods, in order
to enhance fire safety through the development of improved ASTM
test methods.
In the project for standard E 84, each of the 11 participating
laboratories was provided with a comprehensive checklist. This
was the same checklist used by ICBO ES assessors to conduct assessments
of its accredited laboratories. Completing the checklist was the
first phase of the project and a prerequisite to continuing participation
in the research project. The project involved the testing of six
different building materials selected because of their wide use
in construction, and because they represented a wide range of
flamespread and smoke-developed performance. The checklist requested
details on each laboratorys test room, sample conditioning room,
test furnace construction, thermal measurement instrumentation,
gas supply, smoke photometer system and air flow/draft system.
Results of the project were used to evaluate test data for repeatability
and reproducibility. Analysis of the test data was used to develop
a precision and bias statement for the method. Use of the ICBO
ES checklist data enabled the laboratories to identify several
areas where there were deviations from the equipment or the operational
requirements of the method, prior to the tests being conducted.
As a result of the project, several recommendations were made
to refine the ASTM standard, making it more definitive for laboratories
conducting future tests.
Protecting the Built Environment
ICBO ES has learned the value of its technical checklists as assessment
tools for laboratory accreditation from its experience with the
ASTM project. Over the years, ICBO ES has developed a virtual
library of checklists to assist in the technical assessment of
laboratory tests for several disciplines, including tests for
products and materials, related to plumbing, mechanical, structural,
electric-al, geotechnical and fire testing. Through this partnership,
ASTM and ICBO ES have assisted each other in their efforts to
protect the built environment. //
Copyright 2001, ASTM |