Which of the three Greenhouse Gas Protocol business travel methods should I use first, and what do I collect for each?
Go in this order: fuel-based if you know the fuel used in the travel, distance-based if you know distance and mode, spend-based if you only know money spent per mode. The Greenhouse Gas (GHG) Protocol's guide also lists optional hotel nights and the ways to gather travel data.
The order the guide uses
- Does business travel matter to your Scope 3 (based on screening), or is engagement with travel providers relevant to your goals? If yes, continue.
- Is data available on the types and quantities or cost of fuel consumed during travel? If yes, use the fuel-based method.
- If not, is data available on distance travelled? If yes, use the distance-based method.
- If not, is data available on money spent on travel providers? If yes, use the spend-based method.
What to collect for the distance-based method
- Total distance travelled by each mode of transport (air, train, bus, car and so on) for employees in the reporting year.
- Where possible, countries of travel and the specific vehicle types, since factors vary by both.
- Factors per kilometre or per passenger-kilometre for each mode.
- Optionally, hotel nights by hotel type with a factor per night.
- For air travel, the guide says multipliers for radiative forcing may be applied, and if so the specific factor used should be disclosed.
What to collect for the other two
- Fuel-based: the type and quantity of fuel used in the travel, or the cost of that fuel, calculated as in Category 4.
- Spend-based: the money spent on travel, by mode, calculated as in Category 4 with money spent by mode as the activity data.
Where the guide says to get the travel data
If you cannot collect from everyone, the guide lets you extrapolate from a representative sample, for example 400 of 4,000 employees, or group travellers with similar profiles.
- Automatic tracking of distance and mode through a travel agency or other travel providers.
- Tracking through your own expense and reimbursement systems, which may mean adding questions on distance and mode to the claim form.
- Annual surveys of employees.
- Working with travel providers such as transport companies and hotels to get their emissions data.
Which travel is Category 6
- Your own vehicles: Scope 1 for fuel, Scope 2 for electricity.
- Employees travelling on business in vehicles owned or operated by third parties: Category 6.
- Travel between home and work: Category 7.
- Leased vehicles you operate that are not in Scope 1 or 2: Category 8.
The guide's financial services example
- Air: (10 x 10,000 x 5) + (20 x 15,000 x 6) + (100 x 12,000 x 5) = 500,000 + 1,800,000 + 6,000,000 = 8,300,000 kilograms of carbon dioxide equivalent (CO2e)
- Road, with staff sharing cars: (10 / 2 x 50 x 1) + (20 / 2 x 200 x 2) + (100 / 3 x 100 x 4) = 250 + 4,000 + 13,333.33 = 17,583.33 kilograms CO2e
- Total: 8,300,000 + 17,583.33 = 8,317,583.33 kilograms CO2e
- Air is about 99.8 percent of the total
All numbers are the guide's example values and not factors to use. The example labels the second air group as short haul at 15,000 kilometres, while the guide gives an indicative description of short haul as flights under 3 hours; read the example for its arithmetic only (our reading).
What Senseible does here
Senseible reads fuel invoices and electricity bills into monthly records, which covers your own Scope 1 and 2. It does not read flight or train tickets, so the distance and mode data come from your travel agent and expense claims.
- Shared cars on business trips: vehicle-km or person-km
- Short, medium and long haul flights
- Sampling 400 of 4,000 travellers
- Radiative forcing for flights
- Employee own car, business mileage
Last reviewed 2026-11-05. Order and lists follow Chapter 6. Arithmetic multiplies out to the guide's printed 8,317,583.33.