The screws are being tightened further on cars with internal combustion engines, with a move to impose new vehicle noise standards from April 1, 2023.
The National Environment Agency (NEA) yesterday announced it will adopt the latest United Nations (UN) noise standards for vehicles and aftermarket exhaust systems. A table it provided to The Straits Times showed motor vehicle noises will have to fall within a band of between 68 decibels (cars) and 77 decibels (motorbikes) - equivalent to the noise level of a normal conversation.
These values are measurably lower than current Japanese and European standards which Singapore adopts. However, observers have pointed out that older and high-performance vehicles emit noise levels of between 96 and 100 decibels - equivalent to that of a commercial aircraft taking off.
Electric vehicles are significantly less noisy, so much so that regulators in some countries stipulate they must make at least 40 decibels while on the move so that pedestrians can hear them.
The NEA said: "The UN standards are generally more stringent than Singapore's current standards. They also use a test procedure which better reflects actual driving conditions and better accounts for non-exhaust noise."
It will adopt the UN standards from April 2023 for cars and motorcycles, and a year later for commercial vehicles.
Meanwhile, the NEA also said it will tighten the emission standards for motorcycles registered before July 1, 2003, following up on a ruling it announced three years ago. These motorcycles can be used until June 30, 2028, as long as they meet the tightened in-use emission standards.
In 2018, the NEA launched an incentive scheme to encourage owners of older motorcycles to deregister their vehicles early. As at the end of last year, owners of nearly 60 per cent of about 27,000 eligible motorcycles had taken up the offer.
From April 6, 2023, motorbikes registered before July 1, 2003, will need to meet the limits of 4.5 per cent carbon monoxide by volume and 7,800ppm hydrocarbons (for two-stroke engines) or 2,000ppm (for four-stroke engines).
The NEA said most motorcycles will be able to meet the tightened emission standards with proper maintenance. "Owners of older motorcycles who are unsure of their motorcycles' ability to meet the tightened standards are encouraged to tap the early deregistration incentive of up to $3,500, which is available until April 5, 2023."