T-Safe In Focus

Is your point-of-use filter supplier compliant with NETB 2024/03?

The publication of NHS Estates Technical Bulletin NETB 2024/03 introduces a new benchmark for patient water safety, particularly for patients at heightened risk of infection from nontuberculous mycobacteria (NTM) and other waterborne pathogens. A primary focus of this guidance is the specification and deployment of sterilising-grade point-of-use (POU) filters. However, how can Water Safety Groups (WSGs) and Infection Prevention and Control (IPC) teams assess whether the filters being used, or those under consideration, comply with these updated expectations?

This article highlights the NETB requirements for selecting point-of-use filters, outlining the potential clinical risks that can occur when filters fall short, and introduces a downloadable compliance checklist to support procurement and assurance teams.

What Does NETB 2024/03 Say About POU Filters?

Section 3.73 of NETB 2024/03 provides clear expectations on the use of point-of-use filters in healthcare estates. The guidance states that when water is considered safe to use in high-risk areas, such as for drinking or hygiene purposes (bathing, showering, and handwashing) in patient recovery pathways, it must be filtered through sterilising grade point-of-use filters. These filters should meet defined technical and regulatory criteria to ensure continuous patient protection against waterborne pathogens like Pseudomonas aeruginosa, Legionella, and NTM.

Two pages floating on a blue background with content from the NHS Estates Technical Bulletin (NETB) 2024/3 report

Key Selection Criteria for NETB-Compliant POU Filters

Point-of-use filters must meet a range of functional and safety-critical benchmarks, as outlined in the downloadable compliance checklist. Your filter should demonstrate:

  • Validated 0.2 μm filtration for the full life cycle – Proven total retention (not just log reduction) of bacteria under real-life hospital conditions.
  • Leak-free manufacturing integrity – Each filter must pass rigorous pressure testing to detect any potential defects.
  • Robust housing with burst resistance – Casings must withstand mechanical stress and pressure over time.
  • Secure outlet watertight fit with no splashback – To prevent unfiltered water bypass or drain splash contamination.
  • Material compatibility with hospital surface cleaning and water system biocides – Filters must maintain performance during disinfection protocols.
  • Protocols to prevent re-use – Ensuring used filters cannot be reattached, avoiding retrograde contamination.
  • Regulatory compliance and training – Conformity with Water Fittings Regulations and appropriate user training to prevent human error.

These are not optional extras; they are essential patient safety features for filters used in high-risk areas.

Why It Matters: Patient Safety Implications

The use of non-compliant or substandard filters can have serious consequences:

  • Filter degradation could result in bacterial breakthrough, directly exposing immunocompromised patients to harmful pathogens.
  • Leaks or poor fitment may allow uncontrolled water to bypass the filter.
  • Clogged filters without clear diagnostics or escalation protocols may disrupt clinical water supply or result in improper removal and reuse
  • Missed filter installation or exchange can compromise filter performance and create compliance blind spots.

For patients in augmented care, such as lung transplant or stem cell transplant recipients, such failures can be catastrophic. NETB 2024/03 takes a precautionary stance: unless safety is demonstrated and documented, don’t assume it’s safe.

What You Should Do Next

Water Safety Groups and procurement leads should verify that all filters currently in use or under consideration meet the technical and clinical expectations outlined in NETB 2024/03.

Get our free checklist

Use our free downloadable NETB POU Filter Compliance checklist to carry out a quick self-assessment of your current POU filter supplier and products.

A document of NETB 2024/03 Point-Of-Use Filter Compliance Checklist. Visually it consists of three pieces of paper floating in the air on top of a blue circle.

Book a consultation with T-safe

Contact our experts today to learn about T-safe’s gold-standard approach to point-of-use filter validation and compliance with NETB 2024/03.

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