If service or repair is at height, a theoretical and practical training is necessary. The employer devotes eight hours to training with a qualified professional about rules and regulations, risk analysis and conditions of impediment; control measures; individual and collective protection, types of accidents; what to do when there are problems. Training should be given every two years, and repeated if any change occurs;if the worker changes fromone company to another or if he stays over ninety days away from work. When the course finishes, the worker undergoes physical and mental healthtests. All work at height must be preceded by a risk analysis. Before you begin, isolate and signal the area, and check the anchor points and the authorization of those involved.