Air & Transportation

Future Policy for Motor Vehicle Exhaust Emission Reduction(second report) - Chapter 3

Reduction Measures for Exhaust Emissions from Exhaust Pipes of gasoline·LPG Motor Vehicles

(1) Exhaust emission reduction target and achievement time

The measures for motor vehicle exhaust emissions from exhaust pipes (hereinafter referred to as "exhaust pipe emissions") of gasoline-ELPG motor vehicles should be strengthened to emphasize the reduction of emissions of nitrogen oxides and hydrocarbons. It is especially imperative to reduce the exhaust pipe emissions from cold starts. Furthermore, care must be exercised to promote technical development so that low-exhaust emission technology and low-fuel consumption technology are compatible with each other.

From the above discussion, it is appropriate to achieve emission reduction for nitrogen oxides, hydrocarbons, and carbon monoxide from gasoline-ELPG motor vehicles in accordance with the target values for permissible limits as indicated in Attached Table 1. In addition to these measures, it is necessary to extend durability running distances significantly. To accomplish this, it is proper for motor vehicle manufacturers to ensure the performance of exhaust emission control devices at the production stage even after exceeding the distances specified in Attached Table 2.

Passenger cars and light-duty vehicles (gross vehicle weight of 1700 kg or less for trucks and buses) should meet relevant target values by the end of 2000; medium-duty motor vehicles (gross vehicle weight between 1700 kg and 3500 kg) and heavy-duty motor vehicles (gross vehicle weight over 3500 kg) should meet targets by the end of 2001; and mini-sized trucks should meet targets by the end of 2002 . This goal will be possible if design, development, production preparation, etc. are carried out efficiently.

Furthermore, the standards to be enforced in 2000 and 2001 in accordance with this Report will be applied to a wide variety of vehicle models and types and will also strengthen various measures that are scheduled over a short period of time. For example, the motor vehicle noise reduction standards will be strengthened pursuant to the Noise Regulation Law, and the fuel economy target values will be met based on the Rationalization of Energy Consumption Act (Energy-Saving Act). Therefore, when enforcing the exhaust emission standards, special care must be exercised so that the handling of these wide-ranging standards may be performed smoothly.

(2)Measures to maintain performance of exhaust emission control devices during the in-use stage

In order to assure proper functioning of the exhaust emission control device during the in-use stage, in addition to the assurance for durability at the production stage described in Paragraph (1), it is necessary to encourage strict enforcement of routine maintenance for motor vehicles. Furthermore, it is necessary to eliminate any inadequate servicing or illegal modifications of exhaust emission control devices by conducting motor vehicle inspections pursuant to the Road Vehicles Act and spot inspections, which have been hitherto enforced. Moreover, it would be appropriate for motor vehicle manufacturers to install an OBD system (On-Board Diagnostic System) to monitor any malfunction of the exhaust emission control devices because of exposed wires, etc. Furthermore, it would be proper for users to check regularly whether the exhaust emission control devices are functioning normally. It is appropriate that obligatory installation of OBD system be simultaneous with the enforcement of the new target values as set forth in Paragraph (1).

Medium-term and long-term issues for reduction of exhaust emissions from exhaust pipes

It is advisable to advance the technical development of each model of passenger car, mini-sized truck, light-duty motor vehicle, medium-duty vehicle, and heavy-duty vehicle to aim for targets that reduce by half the new targets set forth in Paragraph (1) by 2005. Furthermore, it is appropriate to set new specific target values, and time schedules, etc. However, it is necessary that these new values be set after technical evaluations have been conducted on the progress of development, etc. for control technologies for the standards based on this report. Moreover, it is advisable that the new values be reviewed based on the new exhaust emission measurement methods when they have been decided.

Furthermore, more than ten years have passed since the actual running mode survey was conducted when the present exhaust emission tests were established. Hence, it is recommended to review the current tests as required by performing the actual running mode survey while referring to the current status of tests that are underway in various foreign countries.