Natural ventilation strategies
The effectiveness of natural ventilation strategies such as opening doors and windows will vary throughout the year, depending on the weather in your area. It is important to keep patient privacy at front of mind when considering natural ventilation methods – neither acoustic nor visual privacy should be compromised for the purpose of increased ventilation.
Simply opening the windows and doors of your practice will not guarantee adequate airflow. Investing in effective mechanical ventilation methods can assist in maintaining privacy requirements and in ensuring consistently adequate ventilation throughout your practice, irrespective of the time of year or weather in your area.
In situations where effective mechanical ventilation is not available, your practice must:
- have a minimum of one natural ventilation opening available (i.e. a door or window) to allow outdoor air to circulate inside. However, it is ideal to have two or more openings available
- keep outdoor-facing windows and doors open as often or for as long as reasonably possible
- keep windows and doors of frequently used rooms open to maximise airflow, where appropriate (tip: consider using fans in these rooms to promote air movement further)
- keep any windows and/or doors located within hallways open at all practical times
- in situations where sufficient natural ventilation might be limited (e.g. during extreme weather periods), your practice might want to open windows and/or doors intermittently for short durations (e.g. for 10 minutes every hour). Staff and occupant thermal comfort and safety should be prioritised.
Remember, maintaining patient privacy remains crucial. Neither acoustic nor visual privacy should be compromised for the purpose of increased ventilation.
Do not open windows or doors to improve air quality in buildings that utilise mechanical ventilation systems unless you have consulted with a ventilation specialist.
Mechanical ventilation strategies
Mechanical ventilation can be used consistently, year-round.
Many practices have individual air conditioning units and/or inbuilt HVAC systems that are designed to distribute fresh outdoor air and recirculated indoor air within the building.
However, it is important to understand if your air conditioner or HVAC system pulls in and distributes fresh outdoor air within your practice, or whether they simply recirculate indoor air. While systems that only recirculate indoor air (such as split-system air conditioners) will help to improve air movement, they must be used in conjunction with mechanical or natural ventilation strategies in order to achieve adequate ventilation results. Find out more under ‘Augmented ventilation strategies’.
Mechanical ventilation systems can be enhanced by:
- disabling control systems that vary the amount of fresh air introduced based on room occupancy or other environmental factors. This will maximise the amount of fresh outside air coming into your practice
- changing relevant settings on your systems to avoid recycling air between rooms or spaces
- directing any exhaust outdoors and away from windows, air intake systems or areas where people may congregate
- operating your mechanical ventilation equipment for as long as it takes to complete a total change of air in a space (as per the manufactures guidance/information) after hours, or when staff and patients are off-site, to flush your practice with clean air post-occupancy
- installing high-grade filters within your HVAC system. Where compatible and feasible, filters can be installed in HVAC systems that do not currently have filters. Please note that installing incompatible or incorrect filters within your ventilation system will not only be ineffective, but can cause serious mechanical damage. Contact your HVAC system’s manufacturer to discuss which types of high-grade filters are compatible with your system and to organise installation.
It is paramount that each of your practice’s HVAC systems and air conditioning units are professionally serviced regularly and as per the manufacturer’s instructions to maintain optimal functionality.
Augmented ventilation strategies
Augmented ventilation devices, or air-recirculation and filtration devices, can be used in conjunction with mechanical or natural ventilation strategies to further improve the indoor air quality of your practice.
Common air-recirculation and filtration devices include:
Air cleaners/purifiers
When used appropriately, air cleaners/purifiers such as those fitted with high-efficiency particulate air (HEPA) filters can assist in improving indoor air quality and are useful additions in areas with poor ventilation. Air cleaners can either recirculate air back into a room, or be ducted to exhaust air to the outside.
It is important to keep in mind that air cleaners/purifiers do not reduce build-up of carbon dioxide (CO2). At high levels, CO2 might affect comfort and concentration. For this reason, ventilation with fresh air is preferred to air cleaning where possible.
If your practice chooses to use air cleaners/purifiers, you should:
- place them in locations within your building with poor ventilation. Consider consulting a ventilation expert to determine best placement and maximise benefits
- ensure that they do not interfere with existing HVAC airflow
- avoid placing them near openings such as windows and doors, near sources of heat or areas that are highly humid or dusty
- use them in conjunction with fans and split-system air conditioners to boost clean air distribution
- operate air cleaner/purifiers in the highest mode available.
Air cleaners/purifiers should be used and maintained in accordance with the manufacturer’s instructions.
Split-system air conditioners/non-ducted air conditioners
Split-system air conditioning systems are designed to boost air movement and recirculation within an indoor space. However, these systems do not typically bring fresh outdoor air inside. For this reason, split-system air conditioners should only be used in conjunction with mechanical or natural ventilation to meet sufficient ventilation requirements.
If you are unsure whether your air conditioning system brings fresh outdoor air inside, or if it simply recirculates indoor air, contact the manufacturer or consult with a ventilation specialist.
Fans
Fans offer a cost-effective and convenient solution to boosting air movement in a range of indoor settings, including general practice. Types of fans include:
- portable fans – these can help to increase the effectiveness of open windows and doors
- extractor fans/whirlybird fans – these fans can be installed in your practice roof to enhance the effects of natural and mechanical ventilation strategies
- electrical fans – these can be installed on the ceiling of appropriate rooms within your practice to increase air recirculation and movement within a space
- box or exhaust fans – these fans can be installed in a window to facilitate air movement in or out of a space, dilute aerosol particles in the space and improve air movement. Toilets within your practice must be fitted with exhaust fans. You can find more information on this in The Royal Australian College of General Practitioners’ (RACGP’s) Infection Prevention and Control Guidelines.1
Considered and well executed fan placement is vital. Should your practice choose to utilise fans for the purpose of improving air flow, you must consider the relevant room’s setup and intended air flow direction.
It is important to avoid:
- positioning fans in a way that might cause contaminated air to flow directly from one person to another
- using high-speed settings.
Instead, aim to:
- direct fan airflow towards a suitable unoccupied space, or above the occupied zone
- use ceiling fans at low velocity and possibly in the reverse-flow direction (this will pull air up toward the ceiling)
To ensure correct use and the safety of patients and staff, organise to have your practice assessed by a ventilation expert prior to installing or setting up fans for ventilation purposes.
Remember: If ever in doubt, and to ensure the safety of patients and staff, organise to have your practice assessed by a ventilation expert.