2.5 Other participant or site devices/equipment
The results for this section are a sum of the manufacture, supply, use and end of life impact of testing kits.
Manufacture
If ‘total number’:
Number procured per trial x device emission factor
Example in which 100 smartphones are procured:
100 x 54.78 = 5,478 kg CO2 eq
If ‘total spend’:
Total spend per trial x device spend emission factor
Example in which $50,000 is spent on devices:
$50,000 x 0.108 = 5,400 kg CO2 eq
If ‘number per participant’:
((Number per participant + (number per participant x overage))
x device emission factor)
x number of participants
Example in which 2 smartphones are procured per participant, with a 50% overage and 100 participants in total:
((2 + (2 x 50%)) x 54.78) x 100 = 16,434 kg CO2 eq
Supply
If ‘local’:
No transport impact
If ‘central’:
If ‘total number’:
(Number of devices procured per trial x device weight
x distance from source country capital to destination capital x air freight emission factor)
+ (number of kits procured per trial x device weight
x default road distance x road freight emission factor)
Example in which 100 smartphones are supplied from US to UK:
(100 x 0.187kg x 6000km x 0.00123 kgkm)
+ (100 x 0.187kg x 1000km x 0.00012 kgkm)
= 140 kg CO2 eq
For multiple countries, it will be necessary to determine the proportion of total participants associated with each country and this proportion applied to the total number of kits, devices etc.
If ‘total spend’:
The impact of supply is included in the manufacture calculations.
If ‘number per participant’:
((Number of devices per participant + (number per participant x overage))
x number of participants in trial country x device weight
x distance from US capital to UK capital x air freight emission factor)
+ (number of devices per participant x participants in trial country x device weight
x default road distance x road freight emission factor)
Example in which 2 smartphones per participant are supplied from US to UK with 50% overage and 20 participants in UK:
((2 + (2 x 50%)) x 20 x 0.187kg x 6000km x 0.00123 kgkm)
+ ((2 + (2 x 50%)) x 20 x 0.187kg x 1000km x 0.00012 kgkm)
= 84.15 kg CO2 eq
Use
Total usage:
(Device electricity use per hour x total number of hours used per participant x electricity emission factor)
x number of participants
Example in which a smartphone is used by 100 participants for 200 hours in the UK:
(0.052 kW x 200 hours x 0.275 kg CO2 eq/kWh) x 100 = 286 kg CO2 eq
End of life (EOL)
If ‘total number’:
(Number of devices x device weight x end of life emission factor)
Example in which 100 smartphones are procured and sent to landfill:
100 x 0.187 x 0.009 = 0.168 kg CO2 eq
If ‘total spend’:
((Total device spend x percentage estimate of waste disposal cost) x end of life emission factor)
Example in which $50,000 is spent on devices, assuming the cost of waste disposal is equivalent to 10% of the total spend:
(50,000 x 10%) x 0.137 = 685 kg CO2 eq
If ‘number per participant’:
((Number of devices per participant + (number of devices per participant x overage))
x device weight x end of life emission factor x number of participants)
Example in which 2 smartphones are procured per participant with 50% overage and 100 participants in total:
(2 + (2 x 50%)) x 0.187 x 0.009 x 100 = 0.5 kg CO2 eq
A device can be declared as the participants own or a device can be re-used for a number of trials.
Own Device
If a participant uses their own pre-existing device, we only account for the 'Use' phase due to the participant already possessing the device, the environmental or fiscal costs associated with its production and disposal are external to this study.
Reused on other trials
For devices shared across multiple trials, we calculate the impact based on the Expected Lifetime Reuses. You will need to enter the average number of times a device is reused. You may use decimals to account for "attrition" (loss, damage, or theft). For example: If a device is intended for 3 uses but 10% are lost or broken, enter 2.7.
The total manufacturing value is automatically divided by the number of reuses. This is the same for EOL where the total disposal value is divided by the number of reuses.