Paragraph 8 I1

The undertaker, in the case of the powers conferred by article 17 (protective work to buildings), must exercise those powers so as not to obstruct or render less convenient the access to any apparatus without the written consent of National Grid (such consent not to be unreasonably withheld or delayed) except in the case of emergency works (as defined in the 1991 Act) in which case the undertaker must use all reasonable endeavours not to obstruct or render less convenient the access to any National Grid apparatus (except, where such powers are exercised over National Grid operational land, where access must never be obstructed or rendered less convenient without the written consent of National Grid).

If by reason of the exercise of the powers conferred by article 17 any damage to any apparatus (other than apparatus the repair of which is not reasonably necessary in view of its intended removal or abandonment) or property of National Grid or any interruption in the supply of electricity or gas (as the case may be) by National Grid is caused, the undertaker must bear and pay on demand the cost reasonably incurred by National Grid in making good such damage or restoring the supply; and, subject to sub-paragraph (3), must—

Nothing in this paragraph imposes any liability on the undertaker with respect to any damage or interruption to the extent that such damage or interruption is attributable to the act, neglect or default of National Grid or its contractors or workers; and National Grid must give to the undertaker reasonable notice of any such claim or demand and no settlement or compromise of it is to be made without first consulting the undertaker and giving them an opportunity to make representations as to the claim or demand.