The blueprints of products we use every day are developed in close reference to international standards. When these designs are developed into manufactured goods, firms cooperate with competent bodies that check conformity of their merchandise with relevant norms. And finally, when products are on the market or are used as equipment at the workplace, specialized authorities monitor to protect consumers, workers and employees from hazard or non-compliant products. UNECE Recommendations included in this publication are developed by international experts and adopted by the responsible national authorities. They are not legally binding, but are used worldwide as a reference by national Governments and standardizing bodies, as well as by organizations that promote regional and international cooperation. This is a revised edition of the recommendations.