Car emissions

Emissions from vehicle exhausts are a significant source of air pollution. Air pollutants in vehicle emissions include:

• carbon dioxide
• carbon monoxide
• fine dust particles
• nitrogen oxides
• unburnt hydrocarbons.

You should try to limit the vehicle emissions produced by your business as they may:

• lead to ill health, such as respiratory problems, in your staff and the public
• cause a nuisance to your neighbours
• contribute to roadside pollution levels in urban areas
• contribute to climate change.

What you must do

Emission limits

Make sure that your vehicles comply with emission limits and weight regulations. The exhaust emission standards are specified in the Ministry of Transport (MOT) vehicle test schemes. These MOT test schemes include exhaust emissions checks for all vehicles except:

• vehicles with fewer than 4 wheels
• vehicles with 2-stroke engines
• hybrid vehicles
• quadricycles
• hydrogen fuel cell vehicles
• electric vehicles

The MOT vehicle testing schemes are operated by:

• Driver and Vehicle Agency (DVA), in Northern Ireland. 
• Driver and Vehicle Standards Agency (DVSA)

You can find exhaust emission limits per types of vehicles in the following links - or, if in doubt, contact the DVA in Northern Ireland or the DVSA in Scotland:

• Northern Ireland Department for Infrastructure: Driver Vehicle Agency's heavy vehicle inspection manual
• Driver and Vehicle Standards Agency: MOT inspection manual for car, private bus and light commercial vehicle 
• Driver and Vehicle Standards Agency: MOT inspection manual for heavy goods vehicle (HGV)
• Driver and Vehicle Standards Agency: MOT inspection manual for public service vehicle (PSV)

The DVA in Northern Ireland, and the DVSA in the rest of the UK, also carry out roadside checks, including the checks on exhaust emissions.

Air Quality Management Areas

Your local council monitors air quality in your area. If the air quality exceeds a certain threshold, it may declare an area to be an Air Quality Management Area (AQMA). Within an AQMA the council may test vehicles at the roadside and issue fixed penalties to drivers whose vehicles fail. Check out if you are in an AQMA:

Defra UK Air: Air Quality Management Areas

Low emission zones

Some local councils are introducing low emission zones (LEZ) to reduce pollution in urban centres. These are areas where you may have to pay a daily charge if your vehicle doesn't meet certain emission standards or qualify for an exemption. Check with your local council, or in Scotland, also on the Low Emission Zones Scotland website, to find out if there are any low emission zones in your area:

• Contact your local council
• Low Emissions Zones Scotland

Stationary vehicles

You must turn off your engine if your vehicle is stationary to reduce exhaust emissions and noise. You can be prosecuted or fined by some local councils if you leave your engine running while stationary.

Good practice

Fuel efficiency and high emission standards

When buying new company vehicles, select models with high fuel efficiency and the highest emission standards both for air pollution and carbon dioxide emissions (CO₂). You can find out the fuel efficiency of a vehicle from the Vehicle Certification Agency (VCA) or Society of Motor Manufacturers and Traders Ltd (SMMT):

• Vehicle Certification Agency: New car fuel consumption and exhaust emissions
• Vehicle Certification Agency: New van fuel consumption and exhaust emissions
• Society of Motor Manufacturers and Traders: New and used - CO₂ emissions data for all cars

You can benefit from tax breaks by buying low emission vehicles.

Reducing vehicle emissions Environmental Topic in NetRegs: Choose low emission vehicles

Alternative fuels and electric or hybrid vehicles

You can reduce your vehicle emissions and possibly reduce running costs by using alternative fuels, such as LPG, electric hybrids or full electric vehicles. See:

• Vehicle Certification Agency: Cars and fuel options
• Energy Saving Trust Scotland: Electric and hybrid vehicles explained
• Energy Saving Trust Scotland: Tool for buying a fuel efficient vehicle
• Energy Saving Trust Scotland: Tool for buying an electric vehicle

You can fit older vehicles with devices that reduce their emissions – for example diesel particulate filters. This can be a cheaper alternative to upgrading engines.

HM Revenue & Customs (HMRC) reward businesses that use cleaner, more fuel-efficient cars. Road tax and National Insurance Contributions (NICs) are linked to the car's exhaust emissions, particularly its CO₂ emissions. You can get more details from the HMRC.
HMRC: Company cars

Driver behavioural changes for fuel efficiency

Service all your vehicles regularly.

Make sure tyres are correctly inflated.

Remove any excess weight by only carrying what you need. Remove roof bars and boxes when they are not needed.

Go on efficient driving programmes - for employees. Fuel efficient driving measures include:

• Keep speed down. Driving at 50-60mph produces the lowest emissions. Driving over 70mph rapidly increases vehicle emissions. It can cost up to 15% more in fuel to drive at 70mph compared with 50mph.
• Keep the vehicle moving if possible. Starting and stopping uses more fuel than a vehicle moving steadily.

Use air-conditioning and other electrical devices sparingly as this increases fuel consumption.

Monitor your fuel consumption to help detect problems early. Set monitoring systems for vehicle performance.

Pre-plan delivery routes to maximise the efficient use of vehicles.

Avoid using vehicles for short journeys. Encourage your staff to use public transport, cycle or walk.

Reduce the impact of necessary journeys by using less-congested routes, avoiding peak travel times and encouraging car sharing.

Energy Saving Trust has a smart phone app to track the fuel you use; if you have the information provided in mind and change your behaviour, this can save you money. 
Energy saving Trust: FuelGood

In this Sector Guideline

Car parking

Carriage of dangerous goods

Refrigerated transport and equipment

Travel plans for education

Travel plans and green transport for offices

Vehicle air-conditioning systems

Vehicle cleaning (including wheel washing)

Vehicle emissions

Vehicle movements and deliveries at construction sites

Vehicle refinishing products