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November 3rd, 2007:

Engine idlers may get warnings

Published in Environment on on November 3rd 2007:

Engine idlers may get warnings

Along with issuing fixed-penalty tickets to drivers who do not switch off their idling vehicle’s engine, the Government is considering issuing warning letters to these drivers upon receiving public complaints, Deputy Director of Environmental Protection Carlson Chan says.

Speaking on a radio talk show today Mr Chan said complaints are often received from the public about pollution caused by drivers that leave their engines running while their vehicle is stopped, and is studying ways to curb the problem.

He agreed that certain old turbo engine models require an idling time before being switched off or their lifespan will be shortened. The Government is consulting local vehicle importers to investigate which models should be granted exemption.

The Government has launched a five-month public consultation on its proposal to ban idling vehicle engines. It is aimed for a mid-2009 implementation.

Mr Chan said a total ban is necessary because air and noise pollution caused by idling vehicles are a nuisance regardless of place and time.

Drivers in Toronto can still switch on engines when their car is stopped if the temperature is below five degrees Celsius or over 27. Mr Chan said the Government open to similar suggestions.

The Government will consult District Councils in the coming five-months, but he said it does not want to add too many exemptions on top of those in the consultation document, as they may pose many difficulties for enforcement.

Mr Chan said the ban will greatly improve pollution on the roads and the rationale is to raise public concern and involvement in environmental protection.

Benefits Of Idling Ban Unclear

Saturday November 3 2007

Chester Yung SCMP

Tell us what good forcing engine switch-off will do, say experts

Scientists and engineers said the proposal to ban idling vehicle engines left unanswered key questions about the extent to which it would reduce air pollution. They urged the government to provide more data to justify the initiative.

‘What is the reduction in emissions after the ban? What is the improvement to air quality? These are the most essential questions and the government still owes us the answers in the consultation paper,’ said Alexis Lau Kai-hon, an atmospheric scientist at the University of Science and Technology.

Professor Lau said the government should be able to release precise calculations of the expected reductions in emissions of sulfur dioxide, carbon monoxide, nitrogen oxides and respirable suspended particulates. ‘I can’t judge whether it is a feel-good policy or an effective tool when these questions are still unanswered,’ he said.

Lo Kok-keung, of Polytechnic University’s mechanical engineering department, said the ban could improve roadside air quality but the information released lacked details.

‘Perhaps the government is still unable to come up with a rough estimate and that’s why it hasn’t put it in the consultation paper,’ Mr Lo said.

He estimated the pollutant emissions in busy districts such as Causeway Bay and Mong Kok could drop by 10 per cent if a ban was implemented.

In the consultation paper, the government compares the emissions of vehicles while running and when stationary with engines idling.

An idling diesel-engined public light bus emits about half the pollutants of one in motion. Cars running on petrol emit almost as much carbon monoxide and hydrocarbons when their engines are idling as when they are in motion.

The government admits emissions from idling engines are ‘small in quantity as compared to emissions from the entire vehicle fleet’, but says they cause air pollution and noise nuisance to nearby pedestrian and shops.

There are 550,000 vehicles on Hong Kong’s roads.

Fung Man-keung, lecturer in automotive engineering at the Hong Kong Institute of Vocational Education, said engines must be switched off for at least three minutes for there to be any effective reduction in the pollutants emitted.

‘According to overseas studies, if a driver keeps turning an engine on and off every two minutes, the time the engine is turned off has no significant impact on pollution and the action merely speeds up the deterioration of engine components,’ Mr Fung said.

Au-yeung Ming, a spokesman for the Motor Transport Workers General Union, which opposes a ban, said vehicle starter motors would wear out much more quickly if the proposal became law.

He estimates the lifespan of a starter motor would be shortened by two years, to five years.

‘If we keep switching the engine on and off while waiting in a long queue, we will only emit more pollutants,’ Mr Au-Yeung said.

Pollution hazard

Vehicles are the second-largest source of air pollution in Hong Kong, contributing to 25% of respirable suspended particulates, 25% of nitrogen oxides and 15% of carbon dioxide

While idling engines do not contribute as much as those in motion, the white paper recognises the problems they cause at ground level in congested areas, and the growing number of complaints

Exemptions from the ban include:

Vehicles which stop at the roadside to let passengers board or alight; the first two taxis or public light buses at a stand; vehicles remaining motionless because of traffic conditions such as traffic congestion, security vehicles