Event GHG Measurement Comparability

Uncategorized Jun 27, 2024

The frustrating thing about measuring GHGs for events is that the inconsistency of approaches used means that not a single apple can be compared with another. 

Over at the Carbon Accounting Alliance Events Working Group, we are edging our way towards working out which inconsistencies of approach we should prioritise for discussion.

If you're an experienced GHG measurer of events, and not a member of that group yet, please do go over and join here. 

I've put together a list of potential areas of inconsistency and I'd love your thoughts on any of those topics. We're not trying to answer the questions yet, just agree on areas that perhaps we should try to sort out. 

You can add your comments here, in the article, or as a comment on the google doc, or if you're in the Carbon Accounting Alliance, via our workspace feed. We'll narrow it all down somehow and do some kind of a voting system.

But for now, consider below a beta-brain dump menu of inconsistencies we might like to explore!

Main Categories:

  • Energy 
  • Plant and Machinery 
  • Water 
  • Waste 
  • Materials 
  • Travel 
  • Transport 
  • Food & Beverage 
  • Accommodation 
  • Digital 

Do you agree with these main categories? 

What other categories do you include, and why do you separate it out? 

Scope 1, 2 and 3 

Few tools or measurement approaches have the facility to identify emissions as Scope 1, 2 or 3. What should the expectation be for categorisation and reporting for events? 

Scope 4 

No tools include this important reduction result measure. Should we create an expectation that all events include this in reporting regardless of whether it is available in tools? 

Ownership Boundaries 

There is no consistency and sometimes complete confusion in measurement tools regarding GHG ownership. Should we establish a common approach to including all GHGs created because of the event but split them across GHG ownership (e.g., sponsors, competing teams, exhibitors)? 

Justifying Measurement Inclusions and Exclusions 

There is no common approach to the decision filter steps events go through to validate and justify inclusion or exclusions. Should we create a common approach that events reporting GHG impacts adhere to, to allow for comparability of reporting? 

GHG Intensity Metrics 

Should we create GHG intensity metrics for events that will allow comparisons? What could they be? 

Travel and Transport 

Do you believe separating Travel (people) from Transport (equipment, supplies, infrastructure) is useful? Should this be standard in all tools? 


Some tools use ICAO EFs, which do not include RFI, and others use the UK Government, which does. Some tools use other uplift factors, such as 8% loading for taxi-ing or air traffic control holds. Should we agree on an RFI or uplift factor approach? 

Uplift Factors 

Some tools apply arbitrary uplift factors. We must identify those used in event GHG measurement and agree on approaches. 


Should fuel used in plant and machinery, and other equipment be included in the ‘energy’ category, or should ‘energy’ be only for electricity and fuel in generators?  or should it be bundled into Transport? Or does it deserve its own category? 

Site Vehicles/Buggies/ATVs 

How do you currently manage site vehicles (buggies, production cars and trucks, motorbikes). 

Renewable Energy 

How should renewable energy be treated within GHG accounting for those regions where opting into a 100% renewable energy tariff is possible? What emissions factor will apply, and does your region consider this as ‘additional’ renewable energy onto the grid? 

Hybrid, Battery, Hydrogen Power 

How do we incorporate this into GHG measurement tools? Not many have this currently. 

Transport and Deliveries 

Not many tools or GHG measurement approaches include the transport impact of equipment, infrastructure and supplies. It is a laboursome process to measure this. Should we agree on proxies, or decision filters, and use agreed-upon empirical data to avoid missing this important element. 

What percentage of total is this on average when you have included it in your measurements? 

Water & Wastewater 

Not many include this. Should it be mandatory, and can we create industry proxies to be applied? 


The emissions factors commonly used (UK Govt) for waste are generalised. Currently, the GHG EF is for transport as the GHGs related to processing the waste are on the carbon account of the user of the new recycled product (e.g., rPET, the new product made from recycled material, compost, etc.) Does everyone realise this? 

Should the transport of waste from the event to the first point in the waste management chain (transfer station, MRF etc) be included, or is it believed this leg is incorporated into the published GHG EFs? Where do we stand as an industry on this? 

What GHG EF do we apply for landfill, where it may have gas extraction? 

Where do we stand on waste to energy (including landfill gas extraction) if the GHGs are still occurring, regardless of some touting it as zero emissions? 


There is inconsistency on approaches to accommodation/hotel nights. Do we need to agree on what category of stakeholder’s hotel nights are included for measurement? 


Some tools and approaches include the pre-production period, such as office impacts, business travel, site visits, and offsite production of onsite elements (e.g. scenic design). How do we get consistency on these topics? 


There is a wide variety of approaches to including materials, from none at all to exquisite detail. The use of EFs is incredibly varied. This all leads to incomparability between GHG measurement outcomes. Do we include materials as an optional informative measure until EFs, approaches, and inclusions are consistent? Would it ever be possible to assign proxies from empirical data? 


Some tools include hiring of equipment, but there is no consistency of approach. How should we include hired equipment? We all know that rented equipment is broken at events, and we bear the costs, effectively owning the equipment. How and should we include this? Do we establish thresholds on dollar or GHG impacts? High-risk categories? 

Food and Beverage 

Apart from a wide range of EFs and approaches to measurement (per meal, event devised EFS from menus, tool-derived proxies, per kg of primary ingredient production, or a hybrid of all), we also have inconsistency in the treatment of F&B and stakeholders. Do we only include F&B consumed at the event? What about hospitality guests brought in by sponsors for a multiple-day visit that includes breakfast, lunch or dinner offsite? 

Do we establish a standard approach to inclusions, measurement and assigning of stakeholder-owned additional F&B? 

Can we create proxy EFs from which all events can be drawn? 


Some tools and measurement approaches include digital, but the approaches are inconsistent. Should we create a commonly used approach?


Many GHG sources are inconsistently included in tools and measurements. Should we create an ‘optional reporting’ category alongside the main GHG measurement? Examples include WTT, Refrigerants, Gas, Pyrotechnics, Fire, Digital. 

WTT – Well to Tank 

The inclusion of WTT impact is not consistently used and is also not available for all regions. How do we include so as not to warp results across various events? Should WTT be included as an addendum to GHG figures? 


Do we try to measure this either for large airconditioned venues or highly inefficient temporary air conditioners trying to cool temporary tented structures? Should refrigerants be included as an addendum to GHG figures? 


Not many tools or measurement approaches allow the inclusion of gas or separate it between plant (e.g., forklifts), cooking (e.g., food trucks), and stage effects. 

Pyrotechnics and Fire 

No tools include these. Should we? 


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