Ventilation in NZ schools during the Omicron wave – results from a preliminary study

Monday, February 28th, 2022 | carra86p | No Comments

Dr Julie Bennett, Dr Tim Chambers and Dr Caroline Shorter*

Ventilation is a key and relatively underutilised public health measure that can reduce the risk of Covid-19 transmission. Last year we outlined the need for adequate ventilation in schools and highlighted the need for nationwide ventilation surveillance. In this blog we provide an overview of the results of carbon dioxide (CO2) monitoring carried out in a variety of schools at the start of the Omicron wave. These results highlight that excessive levels of CO2 can build up in classrooms – and that this can be prevented by window opening. 

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Monitoring CO2 indoors for improving ventilation as a Covid-19 control tool

Wednesday, October 27th, 2021 | carra86p | 1 Comment

Dr Ian Longley and Dr Julie Bennett*

Poor ventilation in indoor settings is widely recognised as a risk factor for the airborne transmission of the virus (SARS-CoV-2) that causes Covid-19. Virus-laden aerosols can remain airborne for hours in indoor spaces with low levels of ventilation. In this blog, we discuss how to use carbon dioxide (CO2) measures as a proxy for estimating the level of ventilation in a building and to guide ventilation improvements in schools and workplaces.

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Reducing the risk of Covid-19 transmission through the use of air purifiers

Tuesday, October 26th, 2021 | carra86p | 5 Comments

Prof Mark Jermy, Dr Julie Bennett, Dr Jason Chen, Phoebe Taptiklis and Dr Caroline Shorter*

Indoor environments increase the risk of transmission for the virus that causes Covid-19 (SARS-CoV-2) by containment and concentration of the airborne virus. However, to reduce such transmission, the particles that carry the virus can be diluted by bringing in as much outdoor air as possible. When good ventilation is not possible, air purifiers can be used as an additional preventative measure to reduce the number of virus-laden particles. Ventilation and purification of indoor air needs to be used alongside public health measures, such as vaccination, staying home when unwell and mask use. This blog outlines some basic principles of using air purifiers to reduce the risk of Covid-19 transmission.

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Throwing Open the Windows: The Need for Ventilation Improvements as Part of Covid-19 Outbreak Control in Aotearoa

Monday, August 30th, 2021 | carra86p | 4 Comments

Dr Leah Grout, Prof Nick Wilson, Dr Julie Bennett, Dr Jennifer Summers, Dr Amanda Kvalsvig, Prof Michael Baker *

The importance of indoor aerosol transmission of the virus that causes COVID-19 is increasingly recognised. In addition to public health measures such as masking and physical distancing, further protections are needed to prevent the spread of the virus. Interventions to improve ventilation and filtration are needed for indoor settings in Aotearoa NZ. In this blog we address the particular need to improve ventilation in three settings: (i) homes with contacts who are self-isolating; (ii) indoor workplaces that have essential workers; and (iii) MIQ facilities.

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