A plant is considered as being under construction once ground has been broken for civil works on a site. This classification can be reviewed if activity is reported to have been halted at the site.
Units refer to the selected production basis for any output. The default unit is tons (tons per annum, US dollars per ton), however the user can alternatively select pounds or even volumetric measures such as US gallons and barrels.
Utilities lists the separate utility services that are needed to balance the energy requirements of the process. Some petrochemical reactions produce significant amounts of energy. Such processes will commonly show a negative steam mass flow per ton of main product, indicating that steam is produced by the reaction.