Ventilation in early learning services

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  • All Early Learning Services
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Ventilation in early learning

The COVID-19 pandemic will continue to require a health and safety response from early learning services to minimise the risk of transmission. The Ministry is continuing to support early learning services to maintain good ventilation in their spaces year-round.

Our advice to early learning services is to maximise fresh-air ventilation capabilities as much as possible while maintaining a comfortable indoor temperature of no lower than 18 degrees C, to help to reduce the risk of transmission of airborne illnesses including COVID-19.

The importance of ventilation

All early learning services are designed to be well-ventilated, either naturally or mechanically. When airborne illnesses are prevalent, maintaining good indoor air quality reduces the risk of airborne transmission by regularly refreshing the air in a space.

The best way to achieve good ventilation is to open windows and doors, either fully or partially, whenever you can. The exception to this is spaces that are fitted with ducted air conditioning systems which do not rely on opening windows to bring in fresh air. Note that heat pumps are not ducted air conditioning systems as they do not bring in fresh outdoor air, they only cool/heat and re-cycle the existing indoor air.

Purpose of this guidance

Our guidance is provided to help early learning services understand how ventilation works, and to assess and mitigate the risks caused by poor ventilation.

Early learning services are encouraged to follow our guidance and fine-tune their ventilation strategies year-round, to cater for the seasonal and outdoor conditions.

Support is available to early learning services who are concerned about maintaining good ventilation. This includes:

  • the ability to purchase suitable portable air cleaners and CO2 monitors from the Ministry’s nominated suppliers at discounted pricing
  • downloadable resources and other useful tools to help early learning services follow the guidance. 

For further ventilation advice and support, please contact ventilation.mailbox@education.govt.nz.

Understanding good ventilation

Good ventilation removes stale air and replaces it with fresh, clean air while maintaining a comfortable temperature and humidity levels for the people in the space.  This helps to improve indoor air quality and to reduce the transmission of airborne illnesses including COVID-19.

Our guidance has been developed to provide advice to early learning services on how they can improve and maintain good ventilation year-round.

Indicators that a space may not be well-ventilated include a feeling of stuffiness, lingering smells and elevated CO2 levels. Sustained and elevated levels of CO2 can impact health and learning outcomes, can cause drowsiness and concentration issues for those in the space, and indicate an increased risk of airborne transmission. 

Actions should be taken to improve ventilation when CO2 levels stay above 800ppm for an hour or more.  These actions become more important if CO2 levels are higher and sustained for more than an hour, noting short peaks of higher CO2 readings are normal and should not be a cause for concern.

Guidance for naturally ventilated spaces

Most New Zealand early learning services are designed with good natural ventilation using windows that can be opened. Early learning services can make the most of this by:

  • Opening all windows and doors, partially or fully as conditions allow, whenever you can. Do not wait for a space to get stuffy before opening windows and doors.
  • Opening lots of windows by a little, rather than a few windows by a lot, to avoid uncomfortable draughts.
  • Opening windows prior to or as soon as people arrive in the space and increase the through the day when the room is vacated.
  • Where possible, opening multiple external windows and doors on the opposite sides of a room to enable a cross flow of air.
  • For spaces that only have external windows and doors on one side of the building, consider also opening doors that connect the space to internal corridors to assist with airflow. If doing this, the adjoining space should be well-ventilated and have its external windows open.
  • Taking regular refresh breaks to flush the space with fresh air, as explained below.
  • Ensuring teachers and staff know how to open windows in all spaces throughout the early learning service, and regularly checking to ensure windows are not being temporarily blocked by classroom furniture, children’s artwork or teaching materials.

Refresh breaks (a "reboot" of the room)

Refresh breaks are recommended to flush a space with fresh air by fully opening windows and doors for a short time – for example, 5-10 minutes. If this does not resolve the stuffiness and quickly reduce the CO2 levels, the windows and doors may need to be open for a longer period of time.  The air in the room will also be refreshed more quickly if the space is unoccupied during the refresh break.

Early learning services can check whether a refresh break was effective by using a CO2 monitor.

Early learning services should regularly check for any property issues that may need to be resolved, such as:

  • Ensuring all windows and doors that were originally designed to open, can still open.
  • Unsticking windows which may have been fixed or painted shut.
  • Replacing missing or broken window winders, hinges, catches, security stays, or closers.
  • Correcting any previous alterations which may be impeding good ventilation.
  • Ensuring windows are able to be used as intended and are not blocked, covered over or been changed so that they cannot be opened.

Guidance for colder weather and seasons

During colder weather and especially during the winter season, it can be less practical to fully open windows and doors.  But on cold days good ventilation can still be achieved by partially opening the windows.

This is because air flow behaves differently at different temperatures. The bigger the temperature difference between the outside and inside, the more efficiently fresh outside air is drawn in through open windows, even if the actual opening size is quite small.  This provides a flow of fresh air for the space while only resulting in minimal temperature loss.

On colder days, take these additional steps to help ventilate your space while balancing comfortable indoor temperatures:

  • Heat: Heat the room before the start of the early learning service day, which will allow people to open windows earlier in the day. Keep heating on throughout the day to stay warm, with windows partially opened whenever possible.
  • Open: Open windows by at least a crack or as much as you can while staying warm. Opening lots of windows a little can be more effective in colder weather. If the weather is bad outside, close what you need to stay comfortable.
  • Reboot: Take refresh breaks to clear the air at different times during the day by fully opening all the windows and doors, preferably while having everyone exit the room. Aim to do this at least four times each day.

Fine-tune your approach through the day as the weather changes. Fully opening windows will achieve the best ventilation, so increase your window openings as it warms up outside later in the day or whenever this can be done while maintaining a comfortable indoor temperature.  You can use CO2 monitors to check that these strategies are working and identify whether adjustments need to be made.

If these tips do not provide good ventilation, early learning services can also try these more specific tactics:

  • Open high-level windows first and wider than low level windows, to reduce the risk of cold draughts in the room.
  • Close the doors before you begin closing windows and reduce or close any windows directly facing the worst weather conditions while leaving others partially or fully open.
  • On a wet day, try to keep wet clothes out of the activity space as bringing them in will make the room more difficult to heat.
  • Adjust the room layout to move children away from open windows, and other areas that may have cooler air or draughts.
  • Ensure children have warm clothes to be worn on the coldest days.

Guidance for warmer weather and seasons

When it is warmer, early learning services should fully open windows and doors whenever possible to make the most of natural ventilation while still maintaining comfortable indoor temperatures.

When hot weather outside is making it too warm inside, early learning services should use their cooling systems (for example, heat pumps) to reduce the indoor temperature. This may require windows and doors to be open less at the warmest times during the early learning service day. Consider resetting the temperature of the room to a comfortable level by having all occupants leave the room, open all the windows and doors fully for a short period to air the space, and then close them and run the cooling system on its highest setting before re-occupying the room and re-opening windows.

Air cleaners can also be used in spaces that are challenging to ventilate.  During warmer months air cleaners will also help remove dust, pollen and other outdoor allergens from the indoor air.

Portable and ceiling fans can provide additional comfort to occupants in the warmer months by moving air and creating a breeze within the room, noting their use is not a replacement for opening windows.  Portable fans should only be positioned where they do not present a health and safety risk.

Guidance for spaces with ducted mechanical ventilation systems

Some early learning services are fitted with ducted mechanical ventilation systems that automatically source fresh air from the outside while also managing the temperature of the room. These are often referred to as HVAC or air conditioning systems. This doesn’t include heat pumps because they don’t supply fresh air from outside.

One way to identify if your space has a ducted mechanical ventilation system is to look for vents in the ceilings or walls that bring in fresh air or extract stale air.

Where ducted mechanical ventilation systems are fitted, the advice above for naturally ventilated spaces doesn’t apply unless the system has specifically been designed to work in conjunction with windows and doors being open.  If not, windows and doors should remain closed to allow the system to work as designed.

A well-configured ducted mechanical ventilation system will provide good ventilation while managing indoor temperatures. Most systems will automatically adjust to warmer or colder weather, but it may be possible for the technician to change the amount of fresh air brought in as the seasons change.  Ensure these systems are:

  • Checked, cleaned and maintained by an appropriately skilled technician in accordance with the system’s warranty and maintenance specifications.
  • Configured to operate for at least two hours before and after the early learning service day.
  • Configured to increase the amount of fresh air brought in by the system and minimise the amount of stale air it filters and recirculates, where this can be done while maintaining comfortable indoor temperatures.

It is preferable for these systems to be activated by CO2 thresholds, enabling them to identify when they need to ensure more fresh air is supplied into the space. You can use CO2 monitors to assess whether the system is working effectively.

Configuration and maintenance of ducted ventilation systems should only be done by appropriately skilled technicians.

For more information, refer to our technical advice for ducted mechanical ventilation systems [PDF, 72 KB].

Guidance for using heat pumps and other heating systems

You can continue to use heat pumps to heat or cool spaces, even when windows and doors are open. Using a heat pump with windows open will be less efficient and may incur some additional power costs but can help balance increasing fresh airflow with comfortable indoor temperatures.

Heat pumps and many other heating systems only heat or cool recirculated air within the space. They do not bring in fresh air, so to achieve good ventilation they are to be used alongside a means of providing fresh air. 

When using heat pumps and other heating systems:

  • Pre-heat the space to a comfortable temperature no lower than 18 degrees C before the early learning service day to improve the draw of fresh air through partially opened windows.
  • Increase indoor heating or cooling during the day, if you need to, to offset the impact on temperature of having the windows open.
  • Reset the temperature of the room to a comfortable level no lower than 18 degrees C after it has been vacated and aired out, by briefly closing all windows and doors and running the system on its highest setting before re-occupying the room and re-opening windows.

Your heat pump or heating system should be regularly checked and serviced, including cleaning its mesh dust filter, to make sure it is operating efficiently.

Other supplementary solutions

Portable air cleaners (purifiers)

Air cleaners are a supplementary solution that filter and recirculate the air within a space.  This can improve indoor air quality and reduce the airborne transmission of illnesses including COVID-19. Air cleaners do not replace good ventilation practices as they do not supply fresh air or reduce CO2 levels.

Air cleaners can offer a modest improvement to air quality in spaces that are challenging to ventilate (e.g. where air flow is low, the air is stale, CO2 levels remain elevated for one hour or more) and when it is impractical to sufficiently open windows to flush the space with fresh air. Their effectiveness is dependent on the air cleaner being correctly sized for the room, running on a high fan speed, and having a quality HEPA filter.

Schools, early learning services and other education providers can purchase air cleaners at a discounted price, directly from the Ministry’s two suppliers: Samsung NZ and Rentokil.

Ceiling fans

Fixed ceiling fans help to circulate warm or cool air around the room. They can provide a small improvement to ventilation when windows are fully open, however are unlikely to result in an improvement when windows are only partially opened.

Fixed extract and supply fans

Fitting well-designed and positioned extract and supply fans that bring in fresh air or push out the stale air can boost natural ventilation in conjunction with, or as an alternative to fully opening all windows and doors.  If you are considering fitting extract or supply fans, you can contact ventilation.mailbox@education.govt.nz to discuss whether they will successfully supplement the existing natural ventilation.

Portable fans

Most non-industrial portable fans do not produce sufficient air movement to offer a notable improvement to ventilation, but they can provide additional comfort to occupants in the warmer months by moving air and creating a ‘breeze’ within the room.

We recommend limiting the use of portable fans as it can be difficult to determine whether they are assisting or interfering with air flow. Portable fans are also noisy and can be a safety hazard depending on how they are positioned in the room.

Assessing ventilation

There are several ways to quickly assess whether a space is well ventilated.

Your senses can give a good immediate indication of whether a space has good airflow – for example if a room feels stuffy or has lingering smells, it may not be well ventilated. You’ll be able to verify this using a CO2 monitor.

If you can’t resolve ventilation issues using our guidance, or you are concerned about ventilation in your early learning service you can contact ventilation.mailbox@education.govt.nz.

Carbon dioxide (CO2) monitoring

Monitoring CO2 levels is one way to quickly assess whether a space is well ventilated when it is occupied. Elevated CO2 levels for a sustained period of time (e.g. over an hour or more) indicate that fresh air isn’t flowing into a space quickly enough to meet the needs of the space’s occupants. A space under 800ppm is considered well-ventilated and when levels start to climb above this level, associated risk of airborne transmission of illnesses such as COVID-19 also begins to rise.

In 2022 we provided a one-off supplementary energy payment to centre-based early childhood services to support them to maintain good levels of ventilation and heating over winter. We also provided a one-off payment of $377.20 (incl GST) to fund portable carbon dioxide (CO2) monitors for centre-based services that currently receive Targeted Funding for Disadvantage. The amount reflects the price of the CO2 monitors available through our chosen supplier.

We advise early learning services to take action to improve ventilation if CO2 levels stay above 800ppm for an hour or more. More detail about these actions is provided in the table below.

Using your portable CO2 monitor to perform spot checks

Spot checks provide an immediate indication of current CO2 levels. If the levels are high, follow our guidance to try to lower them and consider if you should also monitor the space’s CO2 levels over a longer duration as explained below.

Spot checks only provide a snapshot of the current CO2 level and may not represent peak or sustained levels. Short peaks of elevated CO2 levels are common in all indoor spaces and are not a cause for concern. Spot checks are best carried out while the space is fully occupied and in use, to provide the most representative spot-check readings. For a more accurate understanding of ventilation, carry out a full day reading as per below.

  1. Take the CO2 monitor to each space and place it somewhere around 500mm from the floor, away from doors and windows, out of direct sunlight, and at least 1m away from the closest people and in a place where it will not be disturbed or moved. Note breathing directly into or over the device will cause it to report high CO2
  2. Leave the device in the room for at least five minutes before checking the CO2 levels reported on its screen. If temperature readings are also required, extend this to 30 minutes to allow the device to report this accurately.
  3. Repeat this process in a selection of spaces, or all spaces on a regular basis (e.g. fortnightly). Look for patterns and relationships between CO2 levels, who is in the room, doing what, and with windows and doors open or closed.

Using your portable CO2 monitor to gather full day readings

If you have a concern with how the space’s ventilation is changing through the day, you can leave the CO2 monitor in the room for a longer period for it to automatically collect its readings. This will provide a more representative picture of ventilation for that space compared to performing spot checks. The devices will typically store 3-7 days data that can then be downloaded.

  1. Take the CO2 monitor into the space and place it somewhere around 500mm from the floor, away from doors and windows, out of direct sunlight, at least 1m away from the closest people and in a place where it will not be disturbed or moved.
  2. At the end of the day or days, use the smartphone app to view and download the CO2 When downloading and assessing the data, ensure you only review the data linked to that space on that day. Take note of how CO2 levels change based on who is in the room, doing what, with windows and doors open or closed at different times through the day.
Sustained CO2 levels What to do
Less than 800 ppm

Your space is very well ventilated – continue with your current approach.

800-1250 ppm

Open all windows and doors as much as possible, and whenever it is practical to do so each day while maintaining comfortable indoor temperatures.

Ensure all exterior windows are functional and can be opened as originally intended.   This may require some maintenance or minor property improvements.

Consider briefly vacating the room, changing activity, or lowering the occupancy at times through the day to purge and refresh the air in the space.

1251-2000 ppm

Short peaks above 1250ppm throughout the day are common.  If there are consistent and sustained elevations in CO2 levels over 1250ppm over the day, consider:

  • briefly vacating the room at regular intervals (e.g. 5 minutes each hour) with all windows and doors fully open, to purge and refresh the air in the space
  • lower the occupancy or the level of vigorous activity performed in the room

If the elevated CO2 levels continue, you can contact ventilation.mailbox@education.govt.nz

Over 2000 ppm

Peaks of high CO2 levels can also occur. If you have followed the above advice and continue to have sustained CO2 levels over 2000ppm, you can contact ventilation.mailbox@education.govt.nz

Ventilation resources

The Ministry has developed a series of downloadable resources to support early learning services with good ventilation.

Ventilation in a space

A4 Poster: How different ventilation methods compare [PDF, 417 KB]

A4 Poster: Tips for good ventilation in colder weather [PDF, 349 KB]

Technical advice: Ducted mechanical ventilation systems [PDF, 72 KB]

Portable air cleaners

A4 Poster: How to use a Samsung portable air cleaner [PDF, 124 KB]

A4 Poster: Where to position your portable air cleaner [PDF, 109 KB](external link) in a room

CO2 monitoring 

A4 Poster: Help slow COVID-19 by monitoring CO2 [PDF, 267 KB]

Device support

In 2022 we provided a one-off supplementary energy payment to centre-based early childhood services to support them to maintain good levels of ventilation and heating over winter. We also provided a one-off payment of $377.20 (incl GST) to fund portable carbon dioxide (CO2) monitors for centre-based services that currently receive Targeted Funding for Disadvantage. The amount reflects the price of the CO2 monitors available through our chosen supplier.

More information about these devices, including warranty and purchasing details, is provided on this page. If early learning services have further questions, please email ventilation.mailbox@education.govt.nz.  

Aranet4 Portable CO2 Monitors

Purchasing

Early learning services and other education providers can purchase these devices at a discounted price directly from the Ministry's supplier, Butler TechSense Ltd via the web site: https://co2sensor.co.nz/(external link) and by using the voucher code ‘3DUCATION’ at checkout.

If purchasing other CO2 monitor brands or products, we recommend ensuring the device has a nondispersive infrared (NDIR) CO2 sensor and has the ability to download data.

Warranty and support

Aranet4 CO2 monitors come with a 24-month warranty, including coverage of goods damaged in transit.

Early learning services can report any damage or faults with Aranet4 CO2 monitors directly to the supplier, Butler TechSense Ltd. The supplier will send a new monitor to the early learning service along with a pre-paid courier bag to return the damaged/faulty product.

Process for reporting damaged or faulty devices:

  1. Email support@butlertechsense.co.nz, including the following information:
  • Early learning service name
  • Early learning service address and postcode
  • Contact name
  • Contact phone number
  • Contact email address
  • Serial number of the Aranet4 CO2 monitor

Portable Air Cleaners (purifiers)

Purchasing

Early learning services, early childhood services and other education providers can also purchase air cleaners at a discounted price, directly from the Ministry’s two suppliers: Samsung NZ and Rentokil.

If purchasing other air cleaner brands and products, we recommend air cleaners that use H13-14 HEPA filters, have a Clean Air Delivery Rate (CADR) greater than 400 m3/hour, operate at less than 60dB (less than 45dB preferred) and do not use emerging technologies that emit any substances into the air (for example ionisers, plasma discharge, ozone generators, photocatalytic oxidation or hydrogen peroxide).

Samsung AX60 (Medium) and AX90 (Large) air cleaners

Purchasing and consumables

Samsung air cleaners can be purchased at a discounted price directly from Samsung NZ, via the website: https://www.samsung.com/nz/air-care/air-purifier/(external link) and using the voucher code ‘3DUCATION’ at checkout.

Replacement filter consumables can be purchased from the same web site: https://www.samsung.com/nz/home-appliance-accessories/all-home-appliance-accessories/(external link), also using voucher code ‘3DUCATION’ at checkout.

Warranty and support

Samsung portable air cleaners come with a 24-month warranty, including coverage if damaged in transit.

Early learning services can report any damages or faults with air cleaners directly to Samsung, who will arrange for a replacement to be sent immediately and for the faulty product to be picked-up.

Process for reporting damaged/faulty devices:

  1. Call Samsung customer support on 0800 726 786 and select Option 2 (customer support)
  2. Please then select Option 3 (business products)
  3. Samsung will ask for you to provide the following information:
    1. early learning service name
    2. early learning service address and postcode
    3. contact name
    4. contact phone number
    5. contact email address
    6. model number
    7. serial number
  4. Samsung will dispatch a replacement unit immediately
  5. Please keep the filter at your early learning service
  6. Samsung will arrange pickup of the faulty unit. If possible, please re-box the item for transit item

Rentokil InspireAir-72 air cleaner

Purchasing and consumables

The InspireAir-72 air cleaner can be purchased at a discounted price directly from Rentokil. More information about these units can be found online at https://web.rentokil-initial.com.au/inspireair72-education-nz(external link).

These can be purchased by calling 0800 RIPRODUCTS or emailing ri-products-nz@rentokil-initial.com and quoting the voucher code ‘MOEInspire’.

Warranty and support

Rentokil portable air cleaners come with a 24-month warranty, including coverage if damaged in transit. 

Early learning services can report any damages or faults directly to Rentokil, either by calling 0800 RIPRODUCTS or emailing ri-products-nz@rentokil-initial.com.

Evaluation of ventilation report

In August 2022, the ventilation programme initiated a ventilation monitoring initiative which involved continuous monitoring of carbon dioxide (CO2), temperature and humidity levels in 5 centres spread across the country.

This report is based on the data collected, which evaluated the ventilation performance of naturally ventilated early childhood education centres to inform proactive ventilation management and improvement guidelines.

Ventilation in early childhood education and care centres [PDF, 1.3 MB]

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