1 The process of booking access to the Tube network so as to enable "fair and equitable" access for all parties is set out in the contractual Access Code.
2 Access can be booked either:
■ At night, when no trains are running (engineering hours)
■ Or daytime periods, when stations, lifts and escalators or stretches of track are closed to allow the Infracos to make repairs.
3 During engineering hours, usually 01.30-4.30am, the Infraco responsible for that particular section of the infrastructure approves or denies requests for access from other Infracos, PFI contractors and third parties, while LUL denies or accepts requests for closures in accordance with the Access Code. All access is booked using LUL's SABRE (Site Access booking for Railway Engineering) system, which was in use during, and prior to, shadow running.