Point-of-use filters and scheduled shower head replacement both show up under "Legionella control" — which leads some estates teams to treat them as interchangeable options to pick between.

Ask an estates manager what makes a water-safety audit slow, and the answer is rarely the water testing itself.

Legionella gets the attention, but in augmented care units Pseudomonas aeruginosa is often the bigger risk — and it doesn't respond to the same controls.

HTM 04-01 governs water safety across NHS estates. Here's what Parts A, B and C actually require for showers and outlets, without the jargon.