It was mainly focused on 6 environmental factors and from those six factors it was chosen to look further into the global warming potential (GWP).
Aðallega voru greindir 6 umhverfisþættir. Af þessum umhverfisþáttum voru gróðurhúsaloftegundirnar (CO2 ígildin) tekin sérstaklega fyrir.