Presentation by David Osborn to the Safer Healthcare Biosafety Network (1 August 2025)

Summary

David is a health and safety consultant and member of the Covid Airborne Transmission Alliance (CATA).

The Safer Healthcare Biosafety Network (SHBN) is an independent forum focused on improving healthcare worker and patient safety. It is made up of clinicians, professional associations, trades unions and employers, patient organisations, industry, and government agencies with the shared objective to prevent occupational and patient safety incidents and improve occupational health and safety and patient safety in healthcare. It includes representatives from the UK-Health Security Agency, NHS, Health and Safety Executive (HSE), Care Quality Commission (CQC), Public Health, Royal College of Nursing (RCN), British Medical Association (BMA) and many others.

You can watch the video of David’s presentation (20 minutes) and download the pdf presentation slides below. 

Content

David reveals new expert guidance about respiratory protective equipment (RPE), which is required to protect healthcare workers when caring for patients who are infectious with Covid-19 and other airborne diseases such as TB, measles, flu, RSV, etc. This guidance quashes, once and for all, the misguided notion held by authors of Infection Prevention Control (IPC) guidance during the pandemic and today’s National IPC Manuals, that surgical masks (including the fluid resistant variety) are suitable for protecting people against airborne diseases.

The new guidance, prepared by the British Occupational Hygiene Society (BOHS), the Chartered Society for Worker Health Protection and the UK’s leading authority on respiratory protection, has the added credentials of meeting the approval of the HSE, the British Standards Institution, RCN, BMA and others.

A key element of the guidance is that it makes it absolutely clear that it is illegal to refer to surgical masks as 'personal protective equipment'. The term 'PPE' has a very precise interpretation in terms of UK safety legislation.

The use of this misleading term for surgical masks has become widespread in NHS documentation. It demonstrates that the authors either don’t properly understand health and safety legislation and/or do not respect the authority of the regulatory body the HSE, its guidance and approved codes of practice. Incorrectly describing surgical masks as PPE lulls workers into a false sense of security. BOHS acknowledge the helpful input of Professor Andrew Curran (HSE’s Chief Scientific Advisor) in finalising this authoritative guidance and the legal clarifications that it contains.

The section of David’s presentation intriguingly entitled 'Size does matter!' explains the fundamental misunderstanding of IPC authors that 'airborne transmission' via aerosols only relates to droplets and particles that are deemed 'respirable' and are so small that they can pass deep down into the lungs (i.e. 5 microns or less). This fundamental flaw in IPC thinking was plainly evident in guidance produced by the 4-nations IPC Cell during the height of the pandemic and continues to this day, leaving healthcare workers endangered by believing they are protected by surgical masks against airborne diseases when in fact they are not.

David also explains how organisations such as CATA are now reaching out to international partners in Canada and elsewhere, with a common purpose of ensuring that IPC guidance across the world is founded on credible scientific principles, which, at present, it is not.