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LCQ10: Vehicle emission testing
     Following is a question by the Hon Jimmy Ng and a written reply by the Secretary for the Environment, Mr Wong Kam-sing, in the Legislative Council today (November 16):


     Since September 1, 2014, the Environmental Protection Department (EPD) has implemented a new measure to detect, by using roadside remote sensing equipment, petrol and liquefied petroleum gas vehicles with excessive emissions on the road.  When EPD staff find vehicles emitting excessive emissions, they will issue emission testing notices to the vehicle owners concerned, demanding them to fix their vehicles and send their vehicles to a vehicle emission testing centre within 12 working days for an emission test with a chassis dynamometer (commonly called a treadmill). Failure to pass the test may lead to cancellation of the vehicle licences in question by the Commissioner for Transport. Shortly after the introduction of the new measure, the Office of The Ombudsman, Hong Kong (the Office) received complaints from vehicle owners alleging that even though their vehicles had just passed the annual vehicle examination (including the idling emissions test) specified by the Transport Department (TD), they were still notified by EPD that their vehicles had to undergo a treadmill emission test. The Office has found upon inquiry that the test items and relevant standards covered in the annual vehicle examination and those in the treadmill emission test are different. As such, vehicles which have passed the annual examination may not necessarily be able to pass the treadmill emission test. In this connection, will the Government inform this Council:

(1) of the respective average monthly numbers of vehicles which have (i) undergone the treadmill emission test and (ii) failed the test, since the implementation of the new measure (with a breakdown by class of vehicle);

(2) as section 31 of the Air Pollution Control Ordinance (Cap 311) stipulates that an appeal may be made by a vehicle owner within 21 days after the vehicle owner has received EPD's notice of the decision, requirement or specification, of the respective average monthly numbers of appeals (i) lodged by vehicle owners and (ii) allowed since the implementation of the new measure;

(3) given that the leaflets published by EPD on the new measure have not explained in detail the relevant appeal mechanism, procedures and possible litigation fees involved, whether the authorities will review and streamline the appeal mechanism, as well as step up publicity among the public on the details concerned; if they will, of the details; if not, the reasons for that;

(4) whether EPD has regularly reviewed the accuracy of the detection results of the roadside remote sensing equipment; if so, whether EPD found in the past three years cases in which vehicles had been erroneously detected with excessive emissions by the equipment; if there were such cases, whether EPD has followed up with the vehicle owners concerned, such as making compensation and refunding vehicle emission test fees; if EPD has followed up, of the details; if EPD has not followed up, the reasons for that; and

(5) as the Office has, in its direct investigation report on the arrangements for the new measure published in January this year, recommended that EPD and TD enhance their coordination in respect of emission tests for vehicles, whether the authorities will implement that recommendation; if they will, of the details; if not, the reasons for that?



     Poorly maintained petrol or liquefied petroleum gas (LPG) vehicles can emit up to 10 times more pollutants than the normal level, aggravating roadside air pollution. To improve roadside air quality and protect public health, the Environmental Protection Department (EPD) has introduced, since September 1, 2014, roadside remote sensing equipment (RRSE) to monitor the emissions from petrol and LPG vehicles, with a view to alleviating the problem of pollution caused by poorly maintained vehicles. If a vehicle is found by the RRSE to have excessive emissions, the EPD will issue an Emission Testing Notice (ETN) to the vehicle owner under Section 77B of the Road Traffic Ordinance (RTO) (Cap 374). The owner is required to have the vehicle repaired promptly, and then have it tested and passed an emission test conducted with the aid of a chassis dynamometer (dynamometer) at an EPD Designated Vehicle Emission Testing Centre (DVETC) within the period specified in the ETN, for the purpose of ascertaining that the vehicle no longer produces excessive emissions. If a vehicle owner does not comply with the requirements of the ETN or the vehicle fails the emission test, the EPD will inform the Transport Department (TD) to cancel the vehicle's licence. A vehicle owner shall pay the test fee specified in the RTO every time he uses the emission test service of a DVETC.

     My replies to the questions raised by Hon Ng are as follows:

(1) Between September 2014 and October 2016, about 6 600 dynamometer emission tests were conducted. During this period, a total of 325 have failed the dynamometer emission test or missing the deadlines for the test as specified in the ETNs.  Statistics by class of vehicle are as follows:
Class of Vehicle Vehicle Licence(s) Cancelled
Light Goods Vehicle 2
Private Car 280
Light Bus 1
Taxi 42
Total 325

(2) The EPD is authorised by the Commissioner for Transport (Commissioner) to, on an independent basis, enforce the relevant statutory requirements under Part 8A (Testing of Motor Vehicle Emissions) of the RTO and monitor the operation of all DVETCs.  Therefore, the appeal mechanism stipulated in section 31 of the Air Pollution Control Ordinance (Cap 311) is not applicable to the decisions made under the RRSE programme. Under section 33(1) of the RTO, if a vehicle has its licence cancelled by the Commissioner under section 25(1)(b) of the RTO because the vehicle fails the aforesaid emission test, the vehicle owner may, within 21 days of being notified of the cancellation of the vehicle licence, apply in writing to the Commissioner for a review of the Commissioner's decision by a Transport Tribunal. Since the implementation of the RRSE programme in 2014, the TD has received no such application so far.

     To facilitate vehicle owners in making prompt enquiries about their cases upon receipt of ETNs, the EPD has set up a hotline and its information is detailed in the ETNs. As a reminder, it is also stated in an ETN that a vehicle owner should call the EPD as early as possible if he has any objections against the ETN or questions for clarification. Upon receipt of an objection, EPD will review the data collected by the RRSE concerned, and examine whether the grounds for objection are justified (e.g. the vehicle owner can prove that the exhaust system of his vehicle has undergone an overhaul shortly before being caught by the RRSE). If deemed necessary, EPD will also arrange for the vehicle to go through an inspection or testing at a DVETC. The EPD handled about 9 000 relevant enquiries or objections between September 2014 and October 2016. A total of five vehicles were inspected/tested and three ETNs were cancelled eventually. The fees incurred in such inspection or testing were paid by the EPD.

(3) The EPD will examine the implementation of the enquiry mechanism from time to time. Where appropriate, the mechanism and the information contained in the ETN will be enhanced so that vehicle owners may approach the EPD if necessary to solve their problems promptly. We will also continue to review and enhance the publicity for the RRSE programme from time to time.

(4) The RRSE is manufactured in conformity with the California standards of the United States, and these standards are commonly adopted worldwide. To ensure the accuracy of the RRSE when in use, the instruments concerned are calibrated with standard gases at two-hour intervals. If the accuracy of the calibration results is in doubt, the vehicle emission data collected by the RRSE will not be accepted. Moreover, when measuring the emissions of a vehicle, the RRSE automatically deducts the concentration readings of emissions detected before the vehicle reaches the RRSE from those detected after the vehicle passes the RRSE, with a view to ensuring that the actual readings are not affected by residual emissions from other vehicles ahead. As a prudent measure, two sets of RRSE are placed at the same location at a longitudinal distance of about 10 metres. An ETN is issued only when both sets of RRSE show readings of excessive emissions from a vehicle driven normally. We have consulted an expert panel composed of local experts and academics on the RRSE technique and the above application methods, and have obtained its members' endorsement.

     As mentioned above, upon receipt of any objections or queries from vehicle owners, EPD will review the data collected by the RRSE concerned, and examine whether the case is justified. If deemed necessary, we will contact the vehicle owner to arrange for the vehicle to go through an inspection or testing. 

(5) The EPD and TD are following up on the recommendations made by the Ombudsman in her report published on January 28, 2016. The two departments are exploring various options on conducting testing for nitrogen oxides at the same time and same place during annual vehicle examination, having regard to their pros and cons and their impacts on DVETCs in respect of modus operandi, operational costs and fee levels. Upon completion of the related studies, we will consult stakeholders on our proposals.
Ends/Wednesday, November 16, 2016
Issued at HKT 11:43
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