This guide was prepared by H. R. Imbus of Workplace Group, Greensboro, North Carolina, a firm that specializes in occupational health. Updated material was provided by N.C. Department of Labor employee J. Edgar Geddie. The information in this guide was updated in 2013. This guide is intended to be consistent with all existing OSHA standards; therefore, if an area is considered by the reader to be inconsistent with a standard, then the OSHA standard must be followed instead of this guide. To obtain additional copies of this guide, or if you have questions about North Carolina occupational safety and health standards or rules, please contact
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