The idling engine ban was rendered useless for two-thirds of July and August because the weather was too hot or too wet. Drivers were allowed to ignore it on a total of 40 days during the two-month period under the controversial legislation's weather-related exemptions. These were days on which the Observatory issued the very hot weather warning - of 33 degrees Celsius or above - or rainstorm warnings. It meant drivers were allowed to keep their engines running to power the air conditioning. But the exemption days - 21 in July and 19 in August - came as roadside air pollution hit record levels. The air pollution index reached 212 in Central on August 2, the highest level yet recorded in the city with the exception of a sandstorm in 2010. One green activist said it showed the idling ban, implemented last December, was no more than a "paper tiger". Friends of the Earth campaigner Melonie Chau Yuet-cheung said: "It is like it never existed." She said the ineffectiveness of the ban had been expected. For that reason, trying to amend it to "give it some teeth" might not be worthwhile. "It would be much better and more effective to focus on the sources of the air pollution, like the heavy trucks running in the streets," she said. Despite that, the first two penalty tickets were issued for breaches of the ban last month. They were handed to the drivers of a coach and a light van, who were fined HK$450 each. A spokesman for the Environmental Protection Department said the coach driver was caught by inspectors with his engine idling in Tung Chung on August 14 while two days later, the van driver received a ticket in Yuen Long. All drivers are permitted to keep their engines running, while parked for three minutes every hour. But the ban is lifted for the whole of any day on which one of the weather warnings is issued. The exemptions were included in the watered-down legislation that was passed on March 5 last year. Exemptions were also applied to taxi stands, the first two minibuses at stands, private school buses and coaches or buses with at least one passenger. Further exemptions were added after the bill was passed for vehicles of welfare agencies and Salvation Army centres for senior citizens. Green activists called for a better pollution warning system after two days of "life-threatening" levels at the start of last month. Roadside readings in Central hovered at or above 190 for 20 hours from August 1.
