Section 142 in The Petroleum And Natural Gas (Safety In Offshore Operations) Rules, 2008
142. Well barriers .-(1) During drilling and other related well activities, there shall at all times be at least two independent and tested well barriers after surface casing is in place.
(2)Well barriers shall be designed in such a manner that unintentional influx, cross flow to shallow formation layers and outflow to the external environment is prevented.(3)Well barriers shall be designed in such a manner that their performance can be verified.(4)If a barrier fails, during drilling and other related well activities, no other activities shall take place in the well than those to restore the barrier.(5)If a barrier fails, during production, to continue production, additional control measures based on risk assessment study shall be introduced during the period the barrier is restored which shall be informed to all concerned and the barrier shall be restored in shortest possible time.(6)When a well is abandoned, the barriers shall be designed to provide for well integrity for the longest period of time that the well is expected to be abandoned, inter alia in such a manner that outflow from the well or leakages to the external environment do not occur.
