More than 3,000 diesel taxis over seven years old that drivers would normally replace are still running because of uncertainty over subsidies to smooth the switch to liquefied petroleum gas (LPG). Taxi operators have warned the delays will result in even poorer air quality. Lai Hoi-ping, chairman of the Hong Kong Kowloon Taxi and Lorry Owners' Association, said most owners had adopted a wait-and-see attitude over the switch. The Government has proposed a $40,000 grant to each diesel taxi owner but there are fears it is not enough as most taxi owners are heavily in debt.