2.8 Trial site
Trial site calculations
If trial site staff time data are available:
((Trial site staff hours per patient visit x electricity user per staff hour
x electricity emission factor for country or global)
+ (trial site staff hours per patient visit x fuel use per staff hour x heating emission factor))
x number of visits per patient x number of patients
Example in which staff work 3 hours per patient visit at site in UK and 15 patients visit 10 times
((3 hours x 0.664 kWh per hour x 0.289 kg CO2 eq per kWh)
+ (3 hours x 1.39 kWh per hour x 0.2102)) x 10 x 15
= 217.8 kg CO2 eq
If trial site staff time data are not available:
((Patient visit duration x default value x electricity user per staff hour
x electricity emission factor for country or global)
+ (patient visit duration x default value x fuel use per staff hour x heating emission factor))
x number of visits per patient x number of patients
UK Example: 15 patients visit 10 times with average duration of 0.5 hours per visit
((0.5 hour x 3 x 0.664 kWh per hour x 0.289 kg CO2 eq per kWh)
+ (0.5 hour x 3 x 1.39 kWh per hour x 0.2102)) x 10 x 15
= 108.9 kg CO2 eq
Trial site staff travel calculations
If trial site staff travel data are available:
Mode of transport % x average rounds trip distance x mode of transport emission factor
x number of trial site staff x number of trial site visits per staff member
Example in which 100 site staff travel 100km and 50% go by car and 50% by bus to trial site 3 times:
(50% x 100km x 0.2094 kg CO2 eq per km x 100 x 3)
+ (50% x 100km x 0.1271 kg CO2 eq per km x 100 x 3)
= 5,047.5 kg CO2 eq
If trial site staff travel data are not available:
Mode of transport % x average round trip distance x mode of transport emission factor
x number of trial site staff x ((number of patients x visits per patient x staff time per visit)/ 8 hours)
Example in which 100 site staff travel 50km and 100% go by car. 15 patients visit the sites 10 times and staff require 1 hour of time per patient visit.
100% x 50km x 0.2094 kg CO2 eq per km x 100 x ((15 x 10 x 1) / 8) = 19,631 kg CO2 eq
Note: In the first example, it is assumed that the user has input their own data of 100km distance and 50% car and 50% bus transport. The second example then uses the default values of 100% travel by car and a distance of 50km. The current version of the tool requires average data for all sites, rather than replicating the inputs for each site in the trial. The user will need to input the number of trial site staff and the number of times they travel to the site across all sites.