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The Public Right-of-Way Accessibility Guidelines (PROWAG) rulemaking has concluded. The PROWAG final rule has been published in the Federal Register. Please visit the Access Board’s PROWAG page for the guidelines.

Stabilized Engineered Wood Fiber for Accessible Playground Surfaces


Installation and Serviceability Results: Governor Nelson State Park, Wisconsin

December 2004

USDA Forest Service and U.S. Access Board

Prepared by:
Theodore L. Laufenberg, Research General Engineer
Jerrold E. Winandy, Supervisory Research Wood Scientist
USDA-Forest Service
Forest Products Laboratory
One Gifford Pinchot Drive, Madison, WI 53726

The project was conducted cooperatively with the United States Architectural and Transportation Accessibility Compliance Board (U.S. Access Board). The Forest Products Laboratory is maintained in cooperation with the University of Wisconsin. This article was written and prepared by U.S. Government employees on official time and is therefore in the public domain and not subject to copyright.

Laufenberg, Theodore L. 2004. Stabilized engineered wood fiber for accessible trails—Installation and serviceability results: Governor Dodge State Park , Wisconsin . Gen. Tech. Rep. FPL-GTR-155. Madison , WI : U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. 11 p.

A limited number of free copies of this publication are available to the public from the Forest Products Laboratory, One Gifford Pinchot Drive , Madison , WI 53726–2398 . This publication is also available online at Laboratory publications are sent to hundreds of libraries in the United States and elsewhere.

The Forest Products Laboratory is maintained in cooperation with the University of Wisconsin.

The use of trade or firm names is for information only and does not imply endorsement by the U.S. Department of Agriculture of any product or service.

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We gratefully acknowledge Bill Botten, U.S. Architectural and Transportation Compliance Board, for guidance in initiating Phase III of the development of the stabilized engineered wood fiber (EWF) concept and Ted Illjes and Bob Zeager of Zeager Bros. Inc., Middletown , Pennsylvania , for performing the impact tests.

Zeager Bros. Inc. and Beneficial Designs, Inc. (Minden, Nevada) , provided the apparatus for the impact test and the rotational penetrometer, as well as training in their use. Thanks to Zeager Bros. Inc. for the donation of EWF and Midwest Industrial Supply (Canton, Ohio) for the donation of Soil-Sement.

Our thanks to the Wisconsin Department of Natural Resources for offering the park playground as a development site for this study. We particularly note the guidance and support of Anthonette Gilpatrick, ADA Coordinator, Renee Lee, Park Manager, and the staff of Governor Nelson State Park for installing and monitoring the playground site. Volunteer groups who helped to install the playground surfacing included the Rotary Club of Waunakee, Madison Chapter of Telephone Pioneers of America, and Edgewood High School students. We could not have performed the study without the support of Steve Schmieding of the Forest Products Laboratory (FPL) and his wife Jane as well as other FPL staff, namely Carl Syftestad, Lloyd Currier, Ben Henderson, Tim Voelker, Vicki Herian, Nancy Keen, Tom Kuster, and Mary Collet.