Average variable cost designated as the primary proxy for marginal cost, with alternatives permitted upon reasoned determination.
These regulations prescribe the cost concepts and procedural approach for computing cost of production, defining multiple measures including average variable cost, total cost, total variable cost, total avoidable cost, average avoidable cost, long run average incremental cost and average total cost, and direct that average variable cost will generally be used as a proxy for marginal cost while allowing the Commission to adopt alternative cost concepts in specific cases with reasons recorded in writing.

Penalty recovery procedure: administrative demand, set payment window, interest accrual and enforced recovery mechanisms including tax referral.
The regulations require the Secretary to issue a demand notice with the Commission's penalty order and a prescribed payment period, payment by challan to the Pay & Accounts Officer, and entry of receipts in a penalty recovery register. The Commission may grant extensions or installments; defaults render the payer in default. Interest accrues on outstanding penalties, subject to reduction or waiver and adjustment after appellate orders. On continued default the Commission issues a recovery certificate executed by a recovery officer authorising recovery measures including requiring third parties or legal heirs to pay, attachment and sale of property under the Income-tax Act procedures, and reference to the Income-tax authority for recovery as tax due.