From David Stevenson
Newbury, Berkshire
I must admit to being somewhat sceptical of Denis Henshaw’s conclusions
about the hazards of radon and electrical fields, as described by Claire O’Brien
(This Week, 17 February, p 4). I have always understood from textbooks that
alpha particles do not penetrate very far and are mostly stopped by the
epidermis of the skin.
On the more positive side, however, while still being doubtful about the
evidence, it might be a good public relations exercise for the National Grid to
sling earth lines below the lower conductors on power lines (which presumably
are responsible for most of the field at ground level) in residential and
industrial areas. Such lines being at earth potential would screen off most of
the field at ground level. Unfortunately the neutral line, which could otherwise
be useful in this respect, is usually slung from the apex of the pylons. Is my
reasoning correct?
