WHEN the musical Grease opens in London’s West End this summer, and the teenage sweetheart Sandy draws on a symbolic cigarette, warning notices will be in place around the theatre alerting the audience to the danger she poses.

Theatres throughout England may have to post similar signs at every performance in which somebody lights up.

The West End theatres fought successfully to win an exemption for actors from the ban on smoking in public places, which becomes law on July 1. But some are now concerned that onstage smoking may draw complaints from the audience. The London theatre owners are to meet officials from the Department of Health early next month to resolve the issue.

A spokesman for the Piccadilly Theatre, the venue for Grease, said: “We will put up an information sign as we do when there is strobe lighting or pyrotechnical effects.”

The “safety first” policy has already been adopted by the Barbican Theatre, which put up a notice in its foyer saying “This performance contains smoking” when it staged Chekhov’s Three Sisters.

Penny Horner, general manager of the Jermyn Street Theatre, said: “Our front row practically have their feet on the stage so it might be advisable to stick up notices when people smoke. It is bureaucracy gone mad.”

Theatres in England won an exemption from the ban by arguing that smoking could be integral to the plot. However, if an inspector decides it is not essential, both the actor and the theatre company could face fines. In Grease, the moment Sandy lights up signals her teenage rebellion, while a cigarette is seen as an essential prop for the seductress, Mrs Robinson, in The Graduate.

Richard Pulford of the Society of London Theatre, said: “The exemption allows for smoking on stage where it is an artistic requirement. But it is not clear whether we have to tell the audience if there is smoking on stage.”

Opera will also be required to justify every puff. Last week a new production of Benjamin Britten’s opera Death in Venice opened at the London Coliseum with Ian Bostridge as Gustav von Aschenbach almost chain-smoking as he admires the boy he spots on the beach.

English National Opera said it would not post warning signs for the remaining seven performances “because no one has complained”.

A spokeswoman for the Department of Health said: “There is no requirement under the law for theatres to have warning signs but it is up to the theatres to decide. There is no warning that there is a murder or rape on stage but there could be if there is a cigarette.”

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