Hong Kong's air pollution sometimes does not seem to be much of a problem for many of us. Apart from asthmatics, a handful of scientists, doctors and fitness fanatics, the pall of smog hanging overhead may be regarded less as a health hazard than a fact of life. Tourists, sometimes so particular about blue-sky backdrops for their holiday photographs, often find the sun setting on our mist-shrouded skyscrapers beautiful. That our air quality is worse than other great cities of the world, such as London, New York and Sydney, does not keep visitors, businesspeople or expatriate workers away in any great number. The air here is, after all, not the worst in Asia; true, it is not as good as in Singapore, Seoul and Tokyo, but better than in Shanghai, Beijing, Mumbai, Bangkok and Manila. Besides, Hong Kong is our home and no matter that our windows have a film of black soot on them each morning and sometimes the opposite side of the harbour cannot be seen, life goes on. No one would dispute that having clearer skies and cleaner air would be good. Government officials, environmentalists, power company executives and academics have recognised this and steps are being taken to cut pollution levels. Some would say that the measures being taken are enough; this newspaper is among those who think otherwise. The three-part Behind the News series concluding today, 'Our Choking Environment', has examined all aspects of the air we breathe. There is only one conclusion the articles point to: Hong Kong is not taking air pollution seriously enough. No one knows, with certainty, whether most of our smog comes from local sources or is from across the border in Guangdong province. While our monitoring is well-developed, mainland authorities are less stringent in their testing. Cross-border co-operation on cutting emissions is not as robust as it should be, nor is the government taking a hard enough line with the city's main polluters - the power companies - although proposals for reform of the scheme of control arrangements suggest a hardening of the official position. Advances have been made. Most of our taxis run on LPG, many buses and trucks use low-polluting diesel and the power companies are exploring renewable energies such as wind power. But with studies showing that air pollution at present levels contributes to hundreds of deaths a year, an extra $1 billion in health costs and shortened lifespans, much greater effort is needed. Now is the time for action and we can all do our part. Cutting electricity consumption through using more efficient equipment and switching off appliances we do not need is simple. We can also pressure for change: from the government, power companies and industry. Only with a concerted community effort can our grey, increasingly dangerous skies become blue and clean.