The operators of U.K. sports stadiums "will be obliged to produce a plan to protect supporters in the event of a terrorist attack inside or outside the ground" to receive a license in the future, according to Martyn Ziegler of the LONDON TIMES. New guidelines produced as part of the first revision in 10 years to the U.K. government-funded Guide to Safety at Sports Grounds include "the need to plan for terrorist attacks" after incidents outside the Stade de France and at the Manchester Arena. The document, known as "the green guide" and comprising more than 300 pages, also gives "official blessing" to football clubs to follow Tottenham's lead and install seats incorporating barriers that will allow safe-standing areas to be "introduced immediately if the government changes the law." Sports Grounds Safety Authority Head of Inspectorate Ken Scott said that the Nov. '15 terrorist attacks in Paris, including on the Stade de France, led to the revisions of the guide featuring planning for "invacuation," which involves a stadium being locked down to protect those inside. Scott said, "Previous planning has been about the usual egress or if there is an emergency such as a fire inside the stadium. The events at the Stade de France and the Manchester Arena have changed that." Stadium operators will also be required to "look at installing barriers to prevent attacks by cars or vans" -- known as "hostile vehicle mitigation" -- and to ensure that they do not block evacuation routes (LONDON TIMES, 11/5).