I would like to commend Karl Collingwood –Thirlway as a first class legionella control specilaist. I have known and had work carried out by Karl since 2003 when his legionella risk assessment of a complex site in Halifax was very good. The quality and attention to detail was noticeable throughout the documentation and his approach to the works. I am confident that any Council or other organisation that chooses Archer & Stone (and especially Karl) to do auditing services will be pleased with their decision.