The material provided is not advocated as a substitute for such safety measures as sealing and fencing the openings of abandoned and idle mines and the posting of warning signs and similar devices to prevent and discourage entry. If people could be taught to understand the dangers of exploring abandoned and idle mines and quarries, many accidents resulting from such actions would not occur. It is believed this booklet will act as a means of education to end these actions. The need for public awareness and providing additional sources of informational materials is the principal reason for printing/publishing this booklet. The information has been compiled from sources believed to be reliable and to represent the best current information on the subject. No warranty or guarantee is made by MSHA as to the absolute correctness of any representation contained in this booklet.