I put a CO2 monitor in the mesh pocket of my backpack during a short trip to #London last week.

Thread on the observations:

Note the traffic light colour scale:
Green = CO2 below 1000 ppm
Amber = C02 between 1000-1400 ppm
Red = CO2 over 1400 ppm The highest readings were recorded during the Cork-Stansted return flights.
Typical "Batman Ears" profile obtained for both flights due to lack of ventilation during boarding & disembarking.
@Ryanair - a CO2 reading of 4000 ppm is very unhealthy. Turn the ventilation on earlier!

New publication shows that the recommended minimum ventilation rate of 6 air changes per hour (ACH) for a 6 bed ward commonly found in hospitals across Ireland & UK could only be achieved by combining natural ventilation with HEPA filtration.

1/
journalofhospitalinfection.com/article/S0195-… Values for effective ACH were obtained from the measured decay rates of respirable particles (< PM2.5) under different conditions.
Fully open windows alone delivered 4.5 ACH, while the HEPA air filter unit (AFU) alone delivered 4.8 ACH.
The combination delivered 11.2 ACH.

2/

Schools are back and there are many concerned parents and teachers asking what measures are in place to reduce the spread of COVID-19.

Short thread. #edchatie The mask mandate was removed at the end of February 2022, but schools were advised to continue using infection prevention and control measures, such as ventilation.

gov.ie/en/press-relea…

Thread on the CO2 readings that I took during my four short flights with @KLM @KLM_EIR last week.
Remember, CO2 at 800 ppm means that 1% of the air you breathe in has been breathed out by others.
At 1200 ppm the rebreathed fraction is 2%.
At 2400 ppm it is 5%.
#CovidCO2
1/ Flight 1 (Embraer 175 aircraft, 95% full):
~500 ppm in @CorkAirport
Shoots up to 2400 ppm while boarding, drops when air circulation kicks in.
Settles around 1900 ppm mid flight. Rises to 2500 ppm when disembarking.
RH ~30% on plane.

2/

For the last 6 weeks I have been working with the Castle Hotel in Macroom @castleHmacroom on a CO2 monitoring & ventilation project.

Here is a (long!) thread on the very interesting results we obtained.
#covidco2
1/ The Castle Hotel is a traditional family-run hotel. The building is old - last major refurbishment was in the early 2000s. Mechanical and natural ventilation are available in most areas. I was pleased to see that front doors are wide open throughout the day!
2/

Hooray!

The Department of Education @Education_Ire today published updated guidance on ventilation in schools.

It includes further practical advice on natural ventilation, the use of CO2 monitors (some good news for schools here!) and air cleaners.

1/

gov.ie/en/publication… Also, very pleased to report that the guidance incorporates a lot of the advice provided by The Expert Group on ventilation and COVID-19 which includes @Orla_Hegarty @IAQjones @MoyneFlu @MarieCoggins1 @DrInaKelly1, myself and others.

2/

gov.ie/en/publication….

#covidco2
Hairdressers and barbers were allowed to open in Ireland last week, so I lent a CO2 monitor to my friend Nora, who runs a hairdressing salon in Cork city.

The monitor (circled in red) was placed in the middle, unused station, 1-2 m from the chairs.

1/ I gave Nora some simple advice - keep a window open and increase ventilation if the CO2 level rises above 800 ppm.

Results from Day 1 show levels rise to around 800 ppm even with window open.

When Nora noticed this she opened the door slightly and the CO2 dropped rapidly.

2/

Pleased to see this important update to the Irish Government's Work Safely Protocol.
The section on ventilation is greatly enhanced and includes additional advice on HVAC systems, use of CO2 monitors and filtration. enterprise.gov.ie/en/News-And-Ev… Also pleased that the @TheHSA took on board advice from our Expert Group on Ventilation and COVID-19 which includes @Orla_Hegarty @MarieCoggins1 @IAQjones among others...

gov.ie/en/publication…

These cases studies of virus spread in Ireland have been reported on and commented by @ZaraKing @newschambers @Orla_Hegarty @DeeGilhawley among others. Good to see this type of analysis but what about aerosols? - the elephant in the room!...short thread.

irishtimes.com/news/health/ho… Spread in houses - probably caused by close-range transmission. NPHET need to emphasise that distancing AND ventilation is essential, even in small indoor gatherings of up to 6 people. Open doors and windows regularly to clear the air.

Big development in USA as the Center for Disease Prevention and Control acknowledges that exhaled aerosols play a major and possibly dominant role in transmission of coronavirus.
latimes.com/world-nation/s… Side by side comparison of new and old guidance from CDC...

https://twitter.com/HuffmanLabDU/status/1307824377463857153?s=19

Significant drop in #AirPollution levels measured at the Cork #AirQuality monitoring site on @UCC campus due to #COVIDー19 related travel restrictions.
Follow thread for details.
Measurements by @CRAClabUCC and @EPAAirQuality.
Data analysis by Niall O'Sullivan.
#COVID19ireland First measures introduced on 12 March had no major impact on air pollution. But more severe travel restrictions from 28 March have led to reductions of 47% in average NO2 concentration and 32% for PM2.5 compared to previous years.