plants. A way to get a single comparative figure for the process fluid use is by
calculating the total use of hydrocarbons in a plant. This is commonly used in some
European CMS’s and is reported as the total weight in tonnes of hydrocarbon (HC)
per produced unit. This is a rough comparative figure, but is regarded as a better
comparison than trying to weigh different fluid types against each other. It is an
index that can be used at plant-level and the figure obtained should in many cases
correlate somewhat with the reported VOC figure. The total HC-index, IHC, is calculated
similarly to the fluid use index with the addition of the hydrocarbon content
CHC for each product