Ken I appreciate your comments about hearing protection and continuing work whilst Big Ben continues to chime but have you ever stood close to a large bell when it is chiming, I have whilst working on our church bells in our village church, there is a tremendous amount of energy released, way above safe working levels and if that is extrapolated up from a relatively small church bell to a bell the size of Big Ben I wouldn't want to be in close proximity when it was struck. I am coming from the position of one who has a severe hearing loss due to loud noise exposure ( gas turbine engines) and it is something that should be avoided at all costs, in the case I believe Health and Safety have got it right.
Dave