scope:

This method of test covers the specimen fabrication, testing protocols, and laboratory-accelerated weathering of detectable warning systems for the purposes of evaluating durability. This method of test covers the following categories:

Non-Destructive Evaluation Tests:

• Visual and Microscopic Evaluation (Section 6)

• Dome Shape and Geometry Measurement (Section 7)

• Static Coefficient of Friction Measurement, Dry and Wet (Section 8)

• Color Measurement (Section 9)

Destructive Evaluation Tests:

• Resistance to Impact from Falling Tup (Section 10)

• Resistant to Impact from Simulated Snowplow Blade (Cold Exposure) (Section 11)

• Wear Resistance (Section 12)

• Coating and Single Dome Bond Strength (Systems with Coatings or Surface-Applied Single Domes) (Section 13)

Laboratory-Accelerated Weathering-Exposure Regime (Hot and Cold Exposure Categories):

• High Temperature Thermal Cycling (Section 14)

• Abrasion Exposure (Section 15)

• Freeze-Thaw Durability (Cold Exposure Applications only) (Section 16)

• Ultraviolet Light Exposure (Section 17)

Figure 1 illustrates the suite of tests that are available to evaluate the durability of detectable warning systems.

The values stated in SI units are to be regarded as the standard.

This standard method of test may involve hazardous materials, operations, and equipment. It does not purport to address all safety problems associated with its use. It is the responsibility of the user of this standard practice to establish the appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of R 18 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with R 18 alone does not completely assure reliable results. Reliable results depend on many factors; following the suggestions of R 18 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.