The advent of electronic communication enables professionals in noise and hearing conservation to communicate more effectively than ever before with their colleagues in other nations. This fact, added to the harmonization of noise standards by the European community, enables people to watch the development of trends throughout the world. The trend in nations' noise standards is toward the 3-dB (equal-energy) rule, toward A-weighted permissible exposure limits below 90 dB, and toward more specific requirements for audiometric testing and the wearing of hearing protection devices. In addition to protecting workers against hearing loss, several nations include requirements to protect against other adverse effects of noise. Some nations have issued noise standards for specific workplaces, processes, and equipment. Enforcement of noise standards varies considerably among nations, with some nations viewing noise standards merely as recommendations, and others enforcing them seriously.