In estimating emission data and mandatory transfer data for the purposes of providing information under regulation 104, the occupier of a reporting facility must—
(a) if an estimation technique is set out in the relevant industry reporting materials for that type of reporting facility apply either —
(i) that estimation technique; or
(ii) another estimation technique approved for the facility by the Authority under regulation 108(3); or
(b) if no estimation technique is set out in the relevant industry reporting materials which relates to a specific process carried out at the reporting facility or means of discharge, emission or transfer of waste from the reporting facility, apply an estimation technique approved for the facility by the Authority under regulation 108(3).