Filters are another very important factor to consider when buying a vacuum cleaner
. Filtration determins the number of particles that will escape into the air from the exhaust of the vacuum. Filtering the exhaust air is very important to allergy and asthma sufferers. There are three main types of filters to choose from:
- Standard filters (also known as stage filters) filter out the air in stages and are not usually recommended for allergy sufferers. There are usually 4 stages of filter(sometimes refered to as "microfiltration"), but this can can vary.
- HEPA or S-Class filters are designed to capture almost all of the microscopic particles and allergens that are emitted from the exhaust. These type of filters are recommended for allergy sufferers.
- Lifetime filters last for the lifetime of the vacuum cleaner and do not need to be changed. They filter the in-coming air throughout the vacuum. Some HEPA or S-Class filters can also be lifetime filters, but they are often more expensive.