Bitumen contains sulfur compounds most of which are removed during refining, the resulting asphalt cement also contains sulfur compounds which are released at the temperatures above 230°C (446°F). Trinidad Lake Modified Asphalt contains sulfur compounds, which are released at lower temperatures between 170°C (338°F) and 230°C (446°F). The release of sulfur from Trinidad Lake Modified Asphalt tarnishes the copper strip and appears to be related directly to the total TLA content. The copper strip test is designed to assess the qualitative presence of TLA in asphalt cements.

1.1 This practice shall be used for the qualitative determination of Trinidad Lake Asphalt in Trinidad Lake Modified Asphalt Cements obtained from production blends or recovered binder from asphalt paving mixtures.

1.2 It is limited to the binder content of Trinidad Lake Modified Asphalt (Specification D 5710) used in the construction of asphalt pavements.

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 and health practices and determine the applicability of regulatory limitations prior to use.