THE decision to end the so-called opposite runway mode of take off and landing at Kai Tak airport will have a severe impact on the lives of at least 250,000 residents of Kowloon City and Shamshuipo. They will now be subjected to the same ear-shattering noise in the evening and early morning as they suffer during the day (and on those nights when wind conditions preclude an approach over Lei Yue Mun). However, for the millions of passengers who fly in and out of Kai Tak every year, the news is very good. The approach over Kowloon may look unsafe from inside a plane, but it is actually safer than the approach from the east. However remote the chances of a collision with an oncoming plane taking off towards Lei Yue Mun, the staggering growth in air traffic and the pressure on the territory's air-traffic control systems has rendered the system intrinsically unsafe. In such circumstances, environmental considerations must take second place to safety. As one of the world's busiest airports, Hong Kong cannot afford to take risks. Nevertheless, the decision will put renewed pressure on British and Chinese officials to reach a speedy agreement on the financing of the new airport. Over the past 10 years, aircraft movements through Kai Tak have risen from 54,300 a year to more than 131,000. Even without the opposite runway system, the size of the traffic load at Kai Tak has significantly increased the chances of a disastrous mid-air collision. None of the three near-misses which occurred in the first half of 1993 took place while the unsafe system was in operation. Both for the safety of the passengers and the comfort of Kowloon, the audit has made relocation to Chek Lap Kok appear all the more urgent.