Authorities will step up inspections of air conditioning in Olympic hotels and venues in the run-up to next year's Games after athletes and coaches at the national training centre became ill from dirty systems.
The central government will also impose stricter regulations on indoor air quality following an investigation by state media which found that office buildings had never cleaned their air conditioning systems.
The CCTV Weekly Quality Report probe into air quality in buildings in at least five mainland cities found that regulations had little effect because of inadequate penalties.
One rarely cleaned air conditioning system had led to about 40 top athletes and coaches at the State General Administration of Sports' coming down with influenza in January, forcing them to withdraw from competitions.
In another case, more than 2 tonnes of waste - including dead rats and lunch boxes left by construction workers - was collected when the ventilation system of a 19-storey Beijing office building was recently cleaned for the first time since it was built in the early 1990s.
The outbreak of severe acute respiratory syndrome in 2003 led to regulations requiring air conditioning in public places be cleaned at least once a year. But only 200 operators of public places in Shanghai and 100 in Beijing had cleaned theirs, accounting for less than 1 per cent of the total in the two cities, a Ministry of Health official said.