The transport calculations

The transport calculations allow you to estimate the emissions from your fleet, other business travel and staff commuting. The data needed for each calculation tier is indicated in the table below:

Note: Tier 3 calculations not currently included in the tool.
ParameterTier 1Tier 2Tier 3
Activity data

Fuel use by

  • Vehicle type (car, etc)
  • Fuel type (petrol, etc)

Fuel use or Mileage by

  • Vehicle type (car, etc)
  • Fuel type (petrol, etc)
  • Euro standard
  • Vehicle weight class or engine size

Mileage by

  • Vehicle type (car, van, etc)
  • Fuel type (petrol, etc)
  • Euro Standard
  • Vehicle weight class

Also, information on operating conditions

Using the Tier 1 method you can estimate air pollution emissions (NOx, PM10 and PM2.5) from exhaust tailpipe from non-electric vehicles as tailpipe emissions for electric vehicles are zero. The tool does not estimate emissions associated with charging electric vehicles or plug-in hybrids. This method can be used for your own, leased or hired vehicles, staff, or other business travel.              
Using the Tier 2 method you can estimate air pollution emissions (NOx, PM10 and PM2.5) from exhaust tailpipe and non-exhaust sources (tyre, brake wear and road abrasion) from electric, hybrids and conventional vehicles. This method can be used for your own, leased or hired vehicles. The tool does not estimate emissions associated with charging electric vehicles or plug-in hybrids.              
If the user is aware of their vehicle registration date, then the table below could be used to determine their Euro standard per vehicle type. Otherwise, vehicle information (i.e. the date of first registration) could be found from the DVLA website. If the Euro status in the DVLA website is shown as Euro 6AJ, 6AK, 6AL, 6AM, 6AN, 6AO, 6AP, 6AQ or 6AR, the vehicle meets the Euro 6d standards.

Vehicle typeEuro StandardStart DateEnd Date
Passenger CarsPre-Euro 119851992       
Euro 119931996
Euro 219972000
Euro 320002005
Euro 420062010
Euro 520102015
Euro 6 a/b/c20152018
Euro 6 d-temp20192020
Euro 6 d2021 and later
Light Commercial VehiclesPre-Euro 1Up to 1994
Euro 119941997
Euro 219972001
Euro 320022005
Euro 420062011
Euro 520112016
Euro 6 a/b/c20162017
Euro 6 d-temp20182020
Euro 6 d2021 and later
Heavy Duty Vehicles (trucks & buses)Pre-Euro IUp to 1993
Euro I19931996          
Euro II19962001
Euro III20012006
Euro IV20062008
Euro V20082013
Euro VI A/B/C20132019
Euro VI D/E2019 and later
MotorcyclesPre-Euro 1Up to 1999
Euro 120002004
Euro 220042006
Euro 320062016
Euro 420162020
Euro 52020 and later

The heat and power calculations

This element of the tool will estimate air pollutants emissions from combustion of fuels in fixed stationary plants, which are typically associated with generating heat and power. Emissions from stationary combustion devices are dependent on the fuel being burnt, as well as the type of device.


The tool allows emissions to be generated using a Tier 1 method – only taking account of the fuels being burnt – or using a Tier 2 method, which accounts for both the different types of fuel and a very simple categorisation of device types.


The data needed for each calculation tier is indicated in the table below:

ParameterTier 1Tier 2
Activity dataTotal fuel use for each type of fuel.  Total use of electricityFuel use by fuel type and by each type of device, i.e. boilers, engines, gas turbines etc.

The NRMM calculations

For NRMM (non-road mobile machinery)/off-road machinery, activity data are usually expressed in terms of energy output (kWh), but emission factors can also be derived that apply to fuel totals as well as the activity data. Companies are more likely to hold records of fuel purchases, than energy output. However, energy data may be estimated from vehicle odometer readings or deployment schedules and load factor estimates.

The Tier 1 methodology will require the basic fuel use or operational data from NRMM. This calculation does not require any information about the equipment that consumes the fuel, the tool simply uses some sectors' average factors - such as average equipment types, fleet, age, engine size, etc. to estimate the activity data and emission factors and calculate the emissions.

The Tier 2 methodology will require more details on the NRMM equipment using the fuel. In this case emissions are calculated from a bottom-up approach using machinery- or engine-specific emission factors in g/kWh based on the power and emission standard of the engine and estimates of annual hours of use, and load factors of each type of machinery operated by the company.

The data needed for each calculation tier is indicated in the table below:

ParameterTier 1Tier 2
Activity data
  • Annual fuel use (litres), or
  • Annual use (hours) and Average load factor, or
  • Annual energy use (kWh)
  • Fuel use or operational data by:
  • Year of manufacturer 
  • Net power rating 
  • Euro standard
  • Fuel type
  • Net power usage (kW)