Tag Archives for " HVAC filter changes "

Tackling Dust in Your Home

Tackling Dust in Your Home

Dust is one of those things that never completely goes away, like mold, but keeping both at a minimum in your home is key!  There are a lot of weather conditions that increase dust, but in general, heat and low humidity are two of them.  When these occur, you’ll not only see an increase of dust in your home, you’ll be breathing more of it because the less humidity, the longer particles stay afloat.  Yuck!  Getting it under control takes some effort, but we’d like to help!

Invest in the right tools

We see deep discounts all the time on home appliances that look like they make our lives easier–but they end up to be a waste of money.   This is where it pays to research–and only buy what will do the job, not the gadget with the most features.  The tools we’re going to talk about are very important to your family’s health, so we hope that you keep these requirements in mind and buy wisely! 

  1. Air Cleaner

With dust in the air, you can do all the cleaning you want and then–BOOM–the dust continues to fall out of the air after you stop cleaning, not to mention all the dust you are filtering with your nose and lungs!  If you live in a dusty area, an air cleaner that uses HEPA filters is imperative.  

For value and solid performance, Medify Air has a range of air purifiers that is hard to beat.  You can find one for every size room in your home, from small nurseries to “great” rooms, with simple controls and most with filters that can be vacuumed gently once a month on the pre-filter side to extend their life.  They use True HEPA H13 filters, which in general last 3 to 6 months.  

Another great option is the CoWay AirMega Mighty, which has been highly rated for a number of years by the NY Times Wirecutter review for dusty rooms up to 250 square feet.  Their testing has used the same filter for up to a year with good performance (however of course you’ll want to have new filters on hand just in case you are caught in an exceptionally-poor air quality day).  

  1. Dusting, Vacuuming, and Mopping

I wish I could tell you differently, but these chores are a must.  If you invest in the right tool(s), however, you can enjoy your clean surfaces with less work!  Dusting should be done with a dry microfiber cloth (check out this video to learn how to dust properly–yes there are techniques that are more effective with less work!)  Then, get both vacuuming and mopping done at the same time with this ONE TOOL (I’ve touted it in other articles, but here it is again): with the CrossWave floor and area rug cleaner by Bissell ($257).  It leaves your floor cleaner than if you had vacuumed and mopped separately!  It has a rug cleaning function, and it has a HEPA filter included, so no dust is escaping your machine and going back into the air.   For people who have mobility or strength issues, this machine absolutely reduces the straining scrubbing actions that normal mopping requires, and it also comes in a cordless option.  If you check local discount stores, there are many reconditioned models that sell for less than half this price (I got my corded one at Ollie’s).  In addition, of course the manufacturer wants you to use their patented floor cleaner, and states that using any other cleaner will violate the warranty.  Unfortunately, Bissell products mostly rate an “D” grade from the Environmental Working Group for toxicity to humans and the environment, but if you do decide to substitute a non-toxic cleaner, we have just the one for you: a recipe using TotalClean.  TotalClean has no fragrance and no toxicity, you can clean your floors as often as you want without adding more VOCs and chemicals to your home.  Here’s the full recipe for a Bissell-like non-toxic floor cleaner:

Machine Floor Cleaner Concentrate Recipe (this is the concentrated cleaner so you add it in replace of the manufacturer’s cleaner, with the recommended amount of water, adapted from this very informative article):

  • 1-¾  cups TotalClean Concentrate
  • ⅛ cup rubbing alcohol
  • ⅛ tsp dish soap
  • 5-10 drops essential oil (optional)

If you simply must have a separate vacuum and mop, though, make sure the vacuum uses certified true (make sure the label says “true”) HEPA filters with an airtight, sealed filtration system.  You don’t want that dust to be recycled right back into the air!  As for mops, The Maker’s Mop is an ingenious tool for dry and wet-mopping, dusting, and cleaning up after huge spills.  And, being “cordless”, I guess it’s handy to have around in the case of a power outage!  (20 Tips To Prevent And Reduce Dust In Your Home)  

  1. Fresh-air ventilation WITH filtration

If your rooms are stuffy (too much CO2!) and you don’t have central air conditioning, make sure you only open windows with filters in them!  That’s right, screens may prevent mosquitoes and flies from coming in, but they do nothing to filter dust.  Our Window Ventilation Filters are adjustable so that you can still open your windows for fresh air and block out most of the dust. 

If you like to open your windows wide for fresh air often, you should consider replacing the fitted window screens with nanoscreening.  Nanoscreening does cut visibility through the screen somewhat compared to normal insect screens, but many customers like the additional privacy it offers.  AllergyGuard nanoscreen offers a kit that is super-easy to install with double-sided tape.   If you re-screen a few windows with this kit and like how it performs, you can go to their website for a larger roll and video on how to install it with spline, the skinny rubber tubing that is normally used to keep screens in place.  

  1. Change your HVAC filter more frequently.  

If you have a hard time remembering to do this, just enroll in an auto-ship subscription to make it easy to have them available when you need them.  If you’re concerned about changing it too frequently, check out our tips for getting that interval just right.

  1. Don’t carry the dust in with you!

We’ve written a lot about this practice, which ranges from taking your shoes off at the door and using a doormat, to doing your best to clean dusty pets off before they come inside (umm, can we teach them how to brush themselves?)

  1. Minimize.

This says so much in one word.  Minimize the fluffy pillows, fuzzy throws, carpeted flooring (don’t rip out carpet if you’re renting, though, obviously), knick-knacks and tchotchkes, piles of clothing, anything that you can do without, that catches loads of dust (children not included)!   If you want to have area rugs or carpet, consider changing them to wool carpets.  According to a 2015 study, wool carpets significantly improve indoor air quality by rapidly absorbing the common pollutants formaldehyde, sulphur dioxide and nitrogen oxides, known as volatile organic compounds, or VOCs, which are released from many common household items such as cleaners and disinfectants, air fresheners, printers and home furnishings.  A high level of formaldehyde (300 parts per million) was reduced to virtually zero in four hours, and nitrogen oxides from 300 to 5 parts per million in 24 hours, whereas nylon carpets did not perform as well.  The wool carpets retained the formaldehyde and did not remit them into the atmosphere.  When you choose a carpet, low pile heights are favorable so that dust and debris is easier for the vacuum to remove (with your True HEPA vacuum, of course!).    

Do Air Purifiers in Classrooms Reduce Illness?

Do Air Purifiers in Classrooms Reduce Illness?

Ahh, this is certainly one time when I’m glad to be working remotely!  As my co-workers send their children back to school, the illnesses (from the common cold to COVID-19) ramp up again in their families as germs get passed back and forth in classrooms.

In 2021, there was a lot of discussion about how to keep students and teachers safe from COVID-19.  Many school districts rushed out to purchase and install air purifiers, with ensuing debate on which purifiers were effective, or in fact, which were dangerous.  It can be a bit confusing, so I headed online to find studies on what works.  I found that across a wide spectrum of experts, the following three solutions to reducing illness and increasing classroom performance are, in order, 

  1. Fresh air ventilation

  2. HVAC system filter maintenance

  3. Air purifiers

This list really is in order of importance.  First of all, air purification technology is great, but we at HypoAir are always in favor of the most natural option first, one that replicates the outdoors, and that will be fresh air VENTILATION.  That’s right, you can put an air purifier in a classroom, but without a continual supply of fresh air to increase oxygen and dilute rising CO2 and virus and bacteria levels, the air purifier can only do so much.  Fresh air can be supplied through an open window if the weather or outdoor air quality is nice, but there should be fresh air ventilation built into every HVAC system so that air quality outside doesn’t limit the quality of air indoors.  Many buildings in the U.S., especially schools, do not meet recommended ventilation rates. The quantity of ventilation depends on how many people are in the room; it should be 15 cubic feet per minute per person. In one study coauthored by Rengie Chan, a research scientist at Lawrence Berkeley National Labs, 85 percent of the California classrooms included failed to meet the minimum standard of 15 CFM per person. Other studies show many American classrooms have an average ventilation rate of only 6 to 11 cfm per person.(wired.com). 

The problem with estimating actual fresh-air ventilation to a room by HVAC is that unless there is an intake from the outside in the system, air blown into the classroom is just being recirculated through the ducts and maybe only filtered once, not adding any fresh air at all.  This type of estimation requires a person knowledgeable about the building’s HVAC system.  If fresh air intake is included, then one expert (Joseph Allen, a professor at Harvard’s School of Public Health) estimates that for reducing Covid-19 risk, the air in the room should be completely replaced at least five times an hour. In a Boston school, the sensor registered about 400 cfm of fresh air coming in through the unit ventilator in one classroom. The room measured 1,010 square feet and had 9.5 foot ceilings: It had 9,595 cubic feet of air. Multiply 400 cubic feet per minute by 60 minutes, divide it by the volume, and you find that the air only gets turned over 2.5 times an hour, which was not sufficient. (wired.com)  However, when conducting another experiment in the same school, they found they could boost air changes to 17 to 20 air changes per hour by opening windows and doors.

An easier way to determine if ventilation is sufficient is by monitoring the CO2 level.  To demonstrate the effect of reducing CO2 levels on disease transmission,  researchers in Taiwan reported on the effect of ventilation on a tuberculosis outbreak at Taipei University. Many of the rooms in the school were underventilated and had CO2 levels above 3,000 ppm. When engineers improved air circulation and got CO2 levels under 600 ppm, the outbreak completely stopped. According to the research, the increase in ventilation was responsible for 97% of the decrease in transmission.(theconversation.com)

Since the coronavirus is spread through the air, higher CO2 levels in a room likely mean there is a higher chance of transmission if an infected person is inside. Based on the study above, experts recommend trying to keep the CO2 levels below 600 ppm. You can buy good CO2 meters for less than $100 online (check out our post including them); just make sure that they are accurate to within 50 ppm. (theconversation.com) What can it hurt to donate (or get together with other parents to donate) several CO2 sensors with remote readings, in order to check the levels of CO2 in your childrens’ classrooms?  

After fresh-air ventilation has been established, let’s look at air cleaning.  In any HVAC system, there should be at least filters in the air returns and they should be changed regularly.  By increasing the MERV rating on these filters to MERV 13, smaller particles like viruses can be filtered out to reduce illness transmission rates.  Changing the rating of the filters should be done in cooperation with the facilities manager in order not to overload the HVAC system, but it is quite possible even if filter box sizes need to be enlarged (see our post on Air Filter Thickness for how to increase MERV rating without increasing pressure drop). 

Third, air purifiers can be considered.  If the school has done what they can to provide adequate ventilation and HVAC filter maintenance, then air purifiers can add another layer of protection by filtering or killing the germs that get by these first two conditions.  In order to be effective, an air purifier must either:

  • pull all of the air in the room through a filter unit several times an hour, OR

  • Send out a non-toxic disinfectant that disperses to all areas of the room.

The first of these can be accomplished with units that include high-powered fans, but these can be noisy.  Noise in a classroom, just like in your home, can be distracting and debilitating for the teacher and students!  For this reason, air purifiers that depend upon air throughput for efficacy need to be evaluated for noise when running at the optimum fan speed for the size of classroom considered.  Also, replacement parts such as filters need to be considered in the total cost.  The cost of a HEPA filter (and possibly UV lamp) for every purifier, for example, can quickly add up to thousands of dollars a year when changes are needed in a school with dozens of classrooms.  Maintenance of these units will fall on the school’s facilities staff, who are likely already over-burdened with an increased cleaning schedule.  

The second option is one that HypoAir promotes because it really is akin to what goes on naturally outdoors.  Ions are one of nature’s cleaning devices, because positive and negative ions are continually floating through the air and reacting with allergens, viruses and bacteria, deactivating them.  These ions are naturally produced by natural phenomena in the air such as sunshine, lightning, crashing water like at the seashore or a waterfall, and plants.  Indoors, we produce them by passing a small electrical charge through stainless steel “needles” to produce positive and negative ions, which get distributed through the air to every part of the room (like adding drops of dye to clean water, soon every part of the water is changed!).  This is done nearly silently, because powerful fans are not required for distribution (any fans already in use in the room will boost circulation of the unit’s small fan).  In addition, maintenance on HypoAir ionizers is virtually nil, because no filters are required and there are no replacement parts.  The cost of running our ionizers is very small, as they use minimal electricity. 

So what about real world testing of these methods?  The CDC released a study on 123 elementary schools in Georgia in 2021.  The schools included did one of three things:

  1. Nothing

  2. Increased ventilation by opening doors, windows or using fans 

  3. Added HEPA filters to classrooms.

In schools that improved ventilation through dilution methods alone, COVID-19 incidence was 35% lower than the schools that did nothing, whereas in schools that combined dilution methods with filtration, incidence was 48% lower than the schools that did nothing.  The takeaway here is that ventilation and HEPA filtration work, even with some added cost for ventilation modification or filter replacements!  Doing nothing, on the other hand, increases the cost of lost school days, makeup time and medical costs for students and teachers substantially.   

It’s a new world with viruses and allergens challenging young and old alike everywhere, but the wisdom of fresh-air ventilation combined with the technology of purification can make it significantly easier to bear!

Photo by CDC on Unsplash