39. The owner shall ensure that the operator is familiar with the operation and safety measures of a ride before operating it. Among others, the operator shall be knowledgeable in:1° the location and use of safety devices;
2° the loading and unloading procedure;
3° the signals used;
4° the evacuation procedure;
5° the location of emergency and first aid services or of the means of communication with those;
6° the directions for use of portable extinguishers.