HEPA Filter FAQs

These FAQs will you implement HEPA filtration for your business or we can assess, install, and maintain your systems.

How do portable HEPA filters protect against SARS CoV-2?

A: Basically, a HEPA filter traps over 99% of the particles that are less than 0.3 microns in the air. While the SARS CoV-2 virus is around 0.1 microns, it is mostly bound up with other respiratory particles that are larger than 0.3 microns and the HEPA filter has electrostatic properties that captures the smaller particle sizes. 

What settings do HEPA air purifiers work best in?

A: They work best in a room with low ceilings in which people are present for 10 to 20 minutes to multiple hours. They decrease the total "viral load" of small buoyant viral particles that are floating around in the room. They cannot magically filter out the particles that spray between people in a short face to face encounter.  

How do I know how many HEPA filters I need in a room?

A: It depends on what air quality objective you are aiming for. Ideally, a business should aim for four to 6 air changes per hour. Try to achieve this with natural ventilation or with the current installed air conditioning before using portable HEPA filters. While four to 6 is a good goal, in a poorly ventilated environment with less than one air change per hour, just lifting the average number of air changes per hour to two will make a significant difference. Your air conditioning mechanic can tell you how many air changes you are currently achieving (zero if a split system) and then the portable HEPA filter can be used to achieve the desired goal.

Is it better to have more smaller capacity HEPA purifiers or one large purifier?

A: It depends. Having more smaller purifiers helps to cover more of the business and they can be run at a lower noise level than having one large purifier in the middle of the room/facility. It depends on the number of walls/partitions and ceiling height and tolerance for noise from the purifiers.

Should portable HEPA filters be placed near the people likely to bring SARS CoV-2 into the building or near those we are trying to protect?

A: While we can never be certain who will bring the virus into our building, we should strive to place it closer to the likely source. Decreasing the total viral dose in the room as early as possible is important. In a school setting, because transmission is usually from teachers to children, it would normally be placed closer to the teacher, but there can be several placed in a room.

What is the best air purifier technology to use?

A: We like HEPA filter technology. There are alternatives that work fine but HEPA filters have the best track record and validation, use less electricity than the corona discharge technology (and are much cheaper), are simple to maintain (filters changed every 3 to 12 months depending on filter). While the filters do trap virus there is minimal risk in replacing/disposing of the filters. Our program addresses maintenance and safe disposal. Ultraviolet air purifiers have a place but it is more difficult to predict what proportion of virus they will kill/extract from the air than with a HEPA filter. They are probably not worth the extra cost.

For essential services and businesses

Our Services

Low fee services

We have a low fee service model for essential services and businesses and operate as a non-profit.  Any excess beyond operational costs support broader pandemic preparedness.

How much does it cost to have HEPA air purifiers installed?

We are a non-profit so we charge a nominal fee for assessment of the facility (usually $600 for a small office area up to $1400 (both + GST)  for a larger complex space requiring a full day of an engineers assessment time.  We can supply the air filters on a rental and maintenance plan. A typical quarterly fee for supply of air purifiers, installation and maintenance of portable purifiers in a 200 square meeting building with three separate zones would be approximately $840 + GST - depending on your air purification and sound level objectives.

How much does it cost to have our ducted air conditioning modified?

We will work with your existing air conditioning engineers to scope the cost to achieve your ventilation objectives. 

What does the service cover?

The service covers three areas:
1. Assessment service
We meet to discuss your air purification objectives, assess the movements of staff and customers through your building, the current status of fresh and make up air and general ventilation, crowding, CO2 levels.  We demonstrate options in air filters, demonstrate the different power options, sizes and sound levels to assess suitability for your workplace. 

2.   Supply, installation and training staff
Once a portable air purifier regimen is selected we supply, place the purifiers and provide training to staff on how to operate the devices and provide reference guides. 

3.  Maintenance
We will provide online support for questions and make maintenance scheduled visits with a frequency dependent on the specifications of the purifier and the level of ambient pollution (dustier environments require more frequent filter replacement). We will remove and replace filters hygienically ensuring no contamination of the environment. 

How quickly can I get this done?

There is a waiting list but drop us a line via email 

Do portable air purifiers remove bushfire smoke?

In our work we try to use only the most modern, convenient and interesting solutions. We want the template you downloaded look unique and new for such a long time as it is possible.