Improved Engineered Wood Fiber (EWF) Surfaces for Accessible Playgrounds Field Performance Testing: Final Report II

Test Procedures

Accessibility Measures

Periodically over the 6-month exposure and again following the 6-month impact tests, all surfaced specimens were subjected to a low-speed rotational bearing test meant to simulate the weight and action of a front caster wheel on a wheelchair. This test provides quantitative measures of firmness and stability of the surfaces. It has been correlated to the work measurement done in ASTM F1951, Accessibility of Surface Systems, for a wide array of surfacing and floor coverings. This test was performed one week after surface installation and each month thereafter using the Beneficial Designs’ rotational penetrometer and protocol for assessing the bearing/rotational indentation on each surface (Axelson and Chesney, 1999). Each of the seven tests was completed at a unique location around the periphery of the surface.

Impact Attenuation Tests

One set of impact tests were run during this study. This test was completed after the surfaces had been exposed for six months. ASTM F 1292-99 test specifications and F355-95 test methods were used at a constant test drop height of 3.05m (10.0 feet). Each specimen had only three impact tests run in sequence per the specification. Per ASTM F355, the instrumented headform was mounted on a magnetic release over the center of the surface. The first impact was ignored and data collected from the second and third impact test. Samples of EWF will be obtained from each surface for moisture content determination immediately following the impact testing.

Moisture and Durability:

The field systems were installed and exposed outdoors for a minimum of a 6-month period. The intent was to expose these surfaces to a wide range of climatic conditions, freeze-thaw cycles, spring rains and summer heat. The ability of the mat to drain water from its surface and interior was important to reduce biodeterioration and maintain cushioning behavior during freezing temperatures. Evaluation of the surface and the entire mat’s permeability was subjective. Following the 6-month exposure period, we sampled the surface layer and the EWF just below the bonded surface. These samples provide data on wood fiber moisture content and density after 6-months of field exposure. One EWF surface was excavated down through its entire 0.3 m (12 in.) depth to determine the moisture profile of the entire Resin-EWF system. This same surface also had a 50mm (2”) diameter observation pipe so that ground water in the site could be monitored.