In addition, LF tags can survive harsh conditions such as marathon races. The tags are fastened to the competitors' shoes to record the individual's times as they pass the finish line. In fitness centers, RFID tags are also used to access individual lockers, changing rooms, and pool areas. The tags can be placed on key chains, clip-on IDs, or access cards. The durability of the cards allows people to clip the tags onto their bathing suits and wear them in the pool. Another demanding use is in waste management. Many countries have begun tagging waste containers and charging by weight to reduce land fill.