Production of additional evidence may be allowed only when required or where the inspector denied opportunity. Production of additional evidence is barred where the party had possession or knowledge but failed to produce it before the Inspector during investigation; however the Bench may, for reasons recorded, allow such evidence if it requires it to pass orders, or if the Inspector denied sufficient opportunity, directing production before the Bench or another authority and requiring compliance and transmission of records, with the admitted evidence provided to other parties for rebuttal.