According to a posting in news:uk.d-i-y [1] there were faulty fittings which had to be matched and replaced, and involved new mountings being drilled into the church fabric.

AIUI the HSE don't ban the use of ladders for tasks of less than 30 minutes where there is no need to let go of the ladder with both hands.

[1] news:<4dbcccc598dave@davenoise.co.uk>