A Longitudinal Study of Playground Surfaces to Evaluate Accessibility - Final Report

Performance and the Surface Deficiency Score

Upon arrival at the playground site, a visual inspection was conducted at nine pre-determined locations within the play area.  This visual inspection would be used as the same method to conduct an accessibility assessment of the playground surface upon installation and during routine inspections.  A digital level and tape measure were used to identify instances along the accessible routes and at clear floor spaces where the surface running slope exceeded 1:16 (6.25%); the cross slope exceeded 1:48 (2.08%); there was a change in level greater than .50 inch; or an opening greater than .50 inch diameter. 

In an effort to statistically analyze the frequency of identifiable deficiencies between surface types, the Surface Deficiency Score (SDS) was developed.  If a surface location was found to have any of the four deficiencies (excessive running slope, cross slope, change in level, or openings), the location was awarded a value of 1 for each.  An SDS of 0 shows no interruption of the accessible route or clear floor space at the location.  An SDS maximum 4 could potentially be awarded at each location. 

An analysis of the SDS among the sample sites indicated there was significant difference in the number of identified deficiencies between the various types of surfaces.  Table 3 provides the SDS for each surface type.  As might be predicted among public playground owners, the PIP scored the lowest SDS with a Mean = .04, while EWF scored the highest with a Mean = 1.94. 

It should be noted that a summary report of findings after the first year of installation was released in May 2011.  During the first year analysis of 25 sites, the SDS for the EWF was significantly different from the other three surfaces.  The EWF was found to have an SDS Mean = 2.16 and Mode = 3.  In short, within the first 12 months of installation, the EWF locations where found to have more deficiencies with running slope, cross slope and changes in level.  Over the course of the longitudinal study, the Mean SDS for the unitary surface types began to increase over time while the Mean SDS for the EWF leveled out, as shown in Table 4.  This suggests deficiencies were visibly identifiable for EWF within 12 months of installation, whereas visible deficiencies for the unitary surfaces did not become measurable until sometime 24‒36 months after installation.  Reduction in the Mean SDS for PIP and HYB during Year 4 can be attributed to patch repairs conducted prior to expiration of the product warranties. 

The greatest number of deficiencies in the playgrounds surfaced with EWF was identified along the accessible route connecting play elements, at climbers and other ground level components.  EWF surface locations with greater surface area, such as the accessible route connecting play components had more occurrences of uneven wear, while play components meant for aggress or egress showed more signs where the 30 x 48 inch clear floor space had displaced surface material such as the “kick out” area at the ground level components, the bottom of slides and swings. 

Two reoccurring issues were identified among at least four of the TIL sites.  These sites had tiles with visible punctures holes ranging from .50 inch to more than 2 inches in diameter.  Openings in the surface greater than a .50 inch can pose safety concerns for people using assistive devices such as canes, crutches or walkers.  The second issue was with the seams.  At the playground sites where both TIL and EWF were installed together, the EWF had begun to penetrate between the TIL seams either causing the seams to shift, pull apart from one another, or pull away from the subsurface it was affixed to at installation.