Short for 'High Efficiency Particulate Air', HEPA filters help to limit the amount of dust mites, mould spores, grass and ragweed pollen, animal dander and other allergens in your environment. These filters are designed to trap allergens that have settled on your floors and furniture so unlike normal vacuums which re-circulate the air, instead the particles are trapped and only fresh clean air is re-circulated back into the air.
HEPA filters have different ratings for efficiency which are generally posted on the filter itself. There are a couple of different categories of HEPA filters which can make understanding the abilities of your filter a bit confusing until they're explained.
How do I know what type of filter my vacuum has?
- True or Absolute HEPA Filters: These certified HEPA filters have passed criteria to be considered HEPA worthy. They are given a particular serial number when they demonstrate that they can trap at least 99.97 percent of particles of .3 microns or less. Test results will be printed on the filter. These True or absolute HEPA filters are generally more expensive than other HEPA filters, but you are also assured they will perform to the highest standard.
- HEPA Type Filters: HEPA like or HEPA type filters are made in similar ways to true HEPA filters and may even resemble them. However, they don't have to meet the rigid standards that certified ones do so are a less expensive alternative. They capture a lower percentage of particles and that percent can fall even lower for particles of 1 micron and below. Depending on the level of your dust allergy issues, these can be a great lower cost option as well.
- Spotting the difference: Look for the serial number and test results printed on true or absolute HEPA filters. Make sure that the test results at .3 microns are 99.97 percent or above. The size of .3 microns is the testing standard, because most filters will perform better with both smaller and larger particles. Double-check the test results at .3 microns to make sure your filter is a true or absolute HEPA.
How do I know when my filter needs cleaning or replacing?
Your HEPA filter, like other types of filters in your home, is made of dense fibres. If you can see through it when you hold it up to the light, it should still be able to absorb more particles. Filters are white so when they are getting black, it will mean that not enough air will come out of your machine and the motor can burn out. Your machine's paperwork should also advise how to check so that you don't waste money unnecessarily on buying new filters too often.
How often should I replace it?
Depending on the model, the amount of allergens in your home and your family's level of sensitivity, these filters may either need to be replaced regularly although some models require far less frequent changes like once in 10 years. In some canister models, the filter will need replacing as it's made of a paper-like material that doesn't take well to water. So in the end the cost of filters can add up. Other models with bags often include a new filter along with a new set of bags. Still others have lifetime filters which require cleaning regularly but should last the life of the machine if properly taken care of.
Can I wash my filter to make it last longer?
Many newer canister models have more expensive "washable" filters that can be rinsed in cold water and left to dry. For example the Dyson DC26 Multifloor has a lifetime filter that just requires a rinse once a month with cold water to keep it in top form.http://www.currys.co.uk/gbuk/dyson-dc26-multi-floor-cylinder-bagless-vacuum-cleaner-grey-blue-04531753-pdt.html . Your manufacturer's instructions can advise.
Buying a vacuum with a HEPA filter is a great investment in your family's health. Take care of your filter and it will take care of you - so you both can breathe a little easier!