1.1 This specification is applicable to the fire resistance of concrete tunnel linings, fire-resistive materials, and structural tunnel members.

1.2 Concrete mix design, tunnel linings, and passive fire protection methods are specific to each tunnel project. Therefore results of the spalling test are only valid for the specific materials and systems employed during each test, notwithstanding maximum and minimum limitations.

1.3 Tunnels are potentially exposed to ground water, even those passing through elevated terrain, such as mountains, road salt, and maintenance surface washing. Consideration shall be given to potential adverse effects that result, such as material degradation due to these exposures.

1.4 Movement joints shall be considered and their impact on the overall fire resistance shall be assessed by testing. Tests shall be conducted as a system.

1.5 This specification does not address mechanical attachment methods for equipment due to the vast variety of possible methods and loads. However, consideration shall be given to methods that appreciably affect the concrete temperature during the heating conditions. Consideration shall be given to a second test conducted with the attachment to evaluate the effect. The attachment test shall include the largest diameter anchor, the deepest installed anchor, and the largest load applied to the anchor. This requirement results in a single anchor being tested or multiple anchors being tested. If multiple anchors are required to be tested, then each shall be tested under its maximum load.

1.6 This specification requires testing of both horizontal and vertical orientations. For fire-resistive materials, it is generally accepted that the horizontal orientation represents the worst case test scenario.

1.7 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.

1.8 This standard is used to measure and describe the response of materials, products, or assemblies to heat and flame under controlled conditions, but does not, by itself, incorporate all factors required for fire hazard or fire risk assessment of the materials, products, or assemblies under actual fire conditions.

1.9 Fire testing is inherently hazardous. Adequate safeguards for personnel and property shall be employed in conducting these tests.

1.10 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.11 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.