Heron Tower comes under microscope as Sainsbury axes twin-tower scheme.
A safety investigation has been ordered at another proposed tall building in London 鈥� Gerald Ronson's Heron Tower in the City.

A spokesperson for Ronson said the review would be comprehensive, but declined to comment on what form it would take.

The scheme is the second proposed skyscraper to undergo a safety audit in the wake of the terrorist attacks in the USA last month. Developer Irvine Sellar has asked for a review of the design of his London Bridge Tower, which at 66 storeys would be the tallest building in Europe.

The building is to be the subject of a public inquiry next week after its design was criticised by English Heritage.

Meanwhile, it has emerged that J Sainsbury has withdrawn proposals for a twin-tower scheme near Chelsea, west London. The 40-storey towers would have formed part of a supermarket development, but they have been scrapped over fears that they could be seen to be in bad taste because of their resemblance to the former World Trade Centre.

Hamish McKenzie, team leader of London Bridge Tower project manager Bovis Lend Lease, said his team would share the findings of its review with Heron Tower. He said: "We talk to [the backers of] Heron Tower fairly regularly and we will make sure our findings are fairly public."

The London Bridge Tower investigation will be wide-ranging. The team carrying it out is considering encasing steel work to offer greater structural protection and widening staircases.

We talk to the backers of Heron Tower fairly regularly and we will make sure our findings are fairly public

Hamish McKenzie of London Bridge Tower鈥檚 Bovis Lend Lease

McKenzie said his design team was alert to all potential threats including biological ones such as anthrax.

He said: "There is no connection whatsoever between issues of biological terrorism and commercial development in London. But it goes without saying that were any linkage to be demonstrated in the future, then we will review the matter."

Experts believe that buildings should include design features that provide protection against biological attack. Keith Edgell, director of building services at Amec design and engineering, said the creation of such defences was feasible in new buildings but would be much more difficult to install in buildings that had already been built.

Developer Frogmore will also step up safety for its proposed 11-storey One Westminster Bridge scheme, but a review will only take place when the scheme gains detailed planning consent.

Managing director Paul White said: "The final designs will include safety precautions. There's no doubt of that."

Developers are not the only ones re-examining safety after 11 September. The Corporation of London is modifying evacuation procedures in the light of the lessons learned from the attacks.