Workforce Block 2 Seminars

3:00 pm - 3:20 pm

Using Portable Air Purifiers to Reduce Airborne Transmission of Infectious Respiratory Viruses – a Computational Fluid Dynamics Study

Aerosols and droplets generated from expiratory events play a critical role in the transmission of infectious respiratory viruses. Fine aerosols play a crucial role in airborne transmission of respiratory diseases including COVID- 19. Out-patient hospital activity moved to virtual clinics during the pandemic, making effective communication difficult and leading to increased isolation and staff dissatisfaction. Mitigations for aerosol-borne disease spread are needed to make healthcare spaces safer for doctors and patients to safely meet face to face again.
Methods
We used computational flow dynamic (CFD) modelling to investigate the efficiency of portable air purifiers containing HEPA filters as a retrofit mitigation strategy to reduce airborne aerosols in hospital consulting rooms. We modelled a single doctor patient interaction in a room with a chilled beam air conditioning system at 3 air changes per hour, 220C and 50% humidity. We generated a detailed computational mesh including 800,000 elements. We performed 3D transient simulations, with steps of 0.01 s, for 180 s. Both continuous phase (air flow) and discrete phase (aerosols) were taken into account. The discrete phase of aerosols was tracked in a Lagrangian manner, with representative populations of around 200,000 particles being tracked.
Results
Aerosol particle number plateaued around 180 seconds. Clearance efficiency ranged from 25% to 62% depending on where the inlet/suction of the air purifier unit was placed. The best location for a single HEPA filter was on the desk between doctor and patient but highest efficiency was achieved using two devices, one on the desk and a second to the side of the room at the height where aerosols were generated.
Discussion
This work provides practical guidance on a mitigation that can be rapidly implemented in an expedient, cost-effective manner, and may lead to more science informed strategies to mitigate airborne transmission of respiratory infections in hospitals.

SPEAKER

3:20 pm - 3:40 pm

Surgical Plume is Hazardous to the Health of the Surgical Team. Using Remote Sensors in a Healthcare Setting to Monitor Exposure to Surgical Plume Will Help Protect the Healthcare Workforce

Surgical plume is a gaseous byproduct of burning organic material created from heat-producing surgical tools. The operating theatre workforce and patients may experience adverse effects from being exposed to surgical plume when plume evacuation devices and standards of practices are lacking.
Opportunities exist to increase awareness about the health consequences of surgical plume exposure to surgical teams and their patients. Engineers, hospital leadership, policy makers, and multidisciplinary surgical team members can influence practice through advocacy, education, and spreading awareness. To better understand the context of the problem, we will analyze the scientific evidence of the hazards and the health and safety risks of exposure to surgical plume and discuss the standards and best practices that guide protection against exposure to surgical plume.
Key to helping resolve issues over exposure will be covered by examining how the use of innovative ways of using technology to exploit data via remote sensors for measuring particulate which is one of the main component of surgical plume and using this to determine if the plume is not being adequately controlled in order to help the employer (Trust, manger) in protecting people's health.

Having something that alerts staff may just make a big difference to their exposure and their health.

• Your LEV isn't working
• Your surgeon isn't using the on tip extraction
• You are at risk

IOM have been working with clients to replace traditional methods of monitoring exposure which can be challenging in clinical environments and employing sensors where monitoring can be carried out remotely and over more meaningful time periods than can be captured in a site visit.
The interpretation being undertaken by AI allows fast accurate feedback on individual exposure.

Lastly, we will provide you with references and resources for further information on developing policy and surveying for compliance.

SPEAKER