Two-thirds of silicon.com's 12-man CIO Jury panel of UK heads of IT said they have reviewed business continuity plans as a direct result of the terrorist attacks.
That assessment is backed up by a separate report this week by the independent Continuity Forum claiming a 75 per cent rise in inquiries about disaster recovery planning following the bombings.
Many firms were affected by communications problems caused by the mobile networks outage, and also by site access denial, due to cordoned-off areas of the city and the shutdown of the transport network.
Neil Hammond, head of IT, British Sugar, said: "We're battling with the age old perception that disaster recovery and business continuity are an IT issue but the terrorist attacks made a site access denial scenario for our London location very much a real possibility. This has led to a review of our procedures for the London scenario, which has identified a few holes which will be fixed."
Ian Auger, IT director at ITN, said it is always essential to learn how you could have better dealt with the situation that occurred. "We particularly focused on the effects it had on the communications systems and how we could maintain staffing levels," he said.
Others said disaster recovery and continuity plans should be reviewed in response to any major incident.
Frank Coyle, IT director at Edinburgh-based John Menzies Distribution, said: "We reviewed and retested our plans in preparation for the G8 summit at Gleneagles and the associated demonstrations in Edinburgh. The principle, however, is the same - a clear and imminent external threat. If the G8 summit had not taken place, we would have done it as a result of the London experience on 7 July."
The terrorist attacks may also act as a wake-up call for some firms, according to Mike Bufalino, IT director at Sheppard Robson.
"As with any type of 'insurance', unfortunately first-hand experience or close calls are required for senior management to part with large amounts of money. A positive that may come from this truly tragic event is more resilience throughout UK firms," he said.
But others said disaster recovery plans are regularly tested and that UK firms should already be used to the possibility of terrorist attacks.
Jacques Rene, head of IT at Airclaims, said: "Working on the perimeter of Heathrow, we already have comprehensive disaster recovery plans. Although expensive, disaster recovery plans are essential and are worked and tested well before any outage prompts us to dust off the 'shelfware'. Remember the IRA used to target the city."
Today's CIO Jury was...
Steve Anderson, European IT partner, Davis Langdon
Ian Auger, IT director, ITN
Mike Bufalino, IT director, Sheppard Robson
Frank Coyle, IT director, John Menzies Distribution
Neil Hammond, head of IT, British Sugar
Christopher Linfoot, IT director, LDV Vans
Phil Pavitt, CIO, OneTel
Peter Pedersen, CTO, Blue Square
Sean Powley, head of ICT strategy, London Borough of Barnet
Jacques Rene, head of IT & projects, Airclaims
Peter Ryder, head of ICT, Preston City Council
Graham Yellowley, director of technology, Mitsubishi Securities International
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