How long does an air purifier need to clean a room?
Have you heard it said, “A woman’s work is never done?” Her air purifier is also never done. There are six basic reasons why you need to continually clean your air. Understanding each one will help you get the clean air results you want.
once in a while is never enough
The most common misconception about cleaning the air is the belief that it is a single task that once done is finished until another day. Cleaning the air is not like vacuuming the floor, washing dishes or clothes. Using an air purifier for a few hours doesn’t finish the job of cleaning the air.
The reason is simple. Indoor air is in a constant state of change. Particles, gases, and microorganisms are constantly being introduced by such things as foot traffic, coughing and sneezing, normal shedding of fur (dander) from humans and pets, your central heating and air system, and others. activities.
Six facts about getting healthy air
Chances are, you want specific health benefits like allergy or asthma relief. What do you need to know to make sure your air purifier provides those health benefits? Consider the following six problems:
- your personal sensitivity
- dilution of contaminants
- dispersion of contaminants
- Reintroduction of contaminants
- Air Changes Per Hour (ACH)
- Efficiency level of your air purifier
How do these points relate to your clean air effort?
Each person has their own “tipping point.” Personal health and environmental factors make this a moving target. Certain allergens may cause a reaction today but not tomorrow. It depends on your total load of irritants and physical stresses.
The goal of air cleaning is to gradually dilute pollutants with clean air, keeping them below the threshold at which it reacts.
Why am I talking about dilution of contaminants and not total elimination? Because particles and gases don’t stay put for an air purifier to capture them one by one. The normal movement of the particles disperses them equally in the air of the room.
This means that the clean air coming out of your air purifier is almost immediately re-contaminated with untreated air. You cannot keep clean air on one side of the room while cleaning the air on the other side.
That’s why your air purifier needs to run continuously. Constant treatment reduces contaminants and keeps them at a low level.
Countering the cleanliness of the air is the reintroduction of new pollutants. Reintroduction is like a leak in a boat. Over time the ship sinks. Your air quality will also plummet if you don’t get ahead of the reintroduction rate of new pollutants.
Just as the ship needs constant bilge to stay afloat, the air in your room needs continuous cleaning to stay healthy.
This is where ACH, or hourly air changes, comes into play. ACH indicates how quickly you can rid the air in your room of pollutants.
ACH is determined by dividing the cubic feet of clean air your air purifier can deliver in one hour by the cubic feet of the room. Let’s say your room is 12 x 15 with an eight foot ceiling. That’s 1440 cubic feet (12 x 15 x 8). Let’s say your air purifier is rated to deliver up to 165 cubic feet per minute (165 CFM) or 9,900 cubic feet in one hour. Dividing 9,900 by 1,440 reveals that your air purifier can provide 6.8 air changes per hour in this room.
That air purifier would be a great option for that room. Most experts agree that 6 ACH is needed for people with severe respiratory problems. At least 4 ACH is recommended for typical allergy relief. In any case, never less than 2 ACH for any benefit and only with the most efficient air purifier.
Which brings us to the issue of efficiency. Not all of the air that passes through an air purifier may be cleaned. Some may bypass the filter or the machine simply cannot remove 100% of the particles that pass through.
The lower the total efficiency of the system, the more times the air will have to pass through the air cleaner to achieve the same cleaning result as a higher efficiency unit. That is why I recommend using only air purifiers with proven high efficiency of the system. It gets the job done effectively with less ACH and therefore lower fan speeds and less noise.
putting it all together
So how long does it take for an air purifier to clean a room? Initially and with a good 4-6 ACH, about an hour to get to a point that produces good allergy relief. Of course, give your body more time to get rid of its load of allergens. Just remember that you never really finish the job of cleaning the air. You should run your air purifier continuously to keep the air as healthy as possible.
I also recommend that you use the most effective and efficient air purifiers you can. Two excellent resources that rigorously test and prove the value of any air filter they offer are achoo!Allergy.com and AllergyBuyersClub.com. Both sites also offer good educational information on clean air and allergy control.