HEPA Room Air Purifiers are Needed at Many Schools

Protection, Appeal, and Cost are the Three Criteria for Mask Purchases

Rolling Stone Rates Reusable Masks

 

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HEPA Room Air Purifiers are Needed at Many Schools

School administrators continue to struggle with selecting the right ventilation system for classrooms, as more states reopen schools for in-person learning. U.S.-based air purification company, Oransi, offers the following guidance for schools that will allow them to select the right ventilation products, the first time, thereby helping to avoid any delay when reopening.

To achieve good indoor air quality the Environmental Protection Agency (EPA) states there are three strategies: source control (removes the source of the pollutant), ventilation (brings in fresh air from outdoors) and air cleaning (through use of an air purifier). For school ventilation there are two options: a HEPA air filtration system or an HVAC ventilation system. Knowing which option is right for a school depends on the efficiency (percentage of particles of a given size that are removed by the air filter with each air pass) and if enough air is moving for the room size.

Commercial HVAC systems are expensive, time-consuming to upgrade, and generally use lower efficiency air filters that do not remove fine particles such as viruses - allowing them to pass back into a room's air. However, upgrading or installing an HVAC system is the right solution if there is a very large space to clean usually larger than 1,500 square feet and removing viruses or fine particles is not a concern.

But a new HVAC system may not be realistic when a school's budget is limited or the campus buildings are older and source control and proper ventilation cannot be achieved. In this case, HEPA air purifiers may be the best supplemental solution for a school's budget and layout. But how can schools select the right HEPA air purifier? Oransi offers the following tips:

1)      Based on the recommendation of Harvard University School of Public Health, look for 5 air changes per hour (ACH) If a school's existing Commercial HVAC system provides 3 ACH, then the air purifier selected would need to provide 2 ACH as a supplement

2)      Look for a portable air purifier with a HEPA filter.

3)      Look for a high Clean Air Delivery Rate (CADR). This represents the volume of clean air coming from an air purifier. The air must be cleaned quickly in order to remove virus particles. Only a HEPA filter can capture a virus with the proper air flow.

4)      Avoid add-ons such as ionizers or UV lights - a technology that requires a lengthy contact time to remove viruses and airborne particles.

5)      Know the exact square footage of the classroom the air purifier will be placed in. To calculate square footage, measure the length and width of the classroom in feet, and then multiply the two numbers to get the square footage. Also calculate in the ceiling height, as an 8-foot ceiling is often assumed. Then refer to the CADR rating to determine what size air purifier can clean the room.

Oransi is a variation of Oranssi, a Finnish word that means orange. This is tribute to the  founder's heritage that values simple design, ease of use and practical.

The company is based in Austin Texas. Its initial products focused on high quality and affordability especially as it relates to filter replacement costs.  It has since added commercial air purifiers  It searched the world to build the ultimate air purifiers. In Germany it found the largest factory of high performance motors. So the purchaser obtains high performance and reliability with low energy usage. 

 

Protection, Appeal, and Cost are the Three Criteria for Mask Purchases

When the consumer buys an automobile he bases his decision on reliable performance and safety data which has evolved over decades. There are minimum standards set by regulations. But there is a wealth of analysis provided by experts and communicated in the media and by the suppliers.

The mask industry has to create a reliable decision system without the luxury of time. It is almost as if you asked someone in 1910 who had only ridden a horse to choose between a Chevrolet SUV and  a Harley motorcycle.

The ASTM ratings along with similar public mask standards in Europe create a minimum requirement and also a measurement structure. What is now needed is a guidance hierarchy which results in the access to clear choices for the consumer.

This hierarchy includes the background science, testing, evaluation, and conclusions by the industry. Then these conclusions have to be communicated to media, associations, and governments who in turn then make their own rating recommendations.

The guidance for the consumer has to be based not on technical criteria such as breathing resistance but simply on comfort. In fact a mask with more media has lower actual resistance than one with less media even though the testing done at a standard velocity does not reflect this.

For the consumer the three goals are protection, appeal, and cost.

Protection

Protection includes

·         media efficiency

·         in leakage

Protection =100% -in leakage-media penetration. Therefore “protection” is a very good term to use in dealing with the consumer. It accurately reflects his goals. He can readily differentiate between  a mask with a 60% protection versus one with  90%

Quality control is another factor which can be communicated with terms such as excellent or appropriate but also with a negative % reduction in protection. With a good quality control program the projected defect impact will be less than 1%.

Protection factor = 100% - in leakage- media penetration- defects.

Mask fit is critical. Recent recommendations to wear a cloth mask over a surgical mask are indicative of the importance. However, this particular choice creates new variables including not only which combination of masks is chosen but how they are actually worn.

Some mask companies have five different mask sizes. They have done extensive testing of leakage under various movements.  They have programs to make sure purchasers have good guidance on wear. This category could be classified as “donning”. There is likely to be less consumer error in picking the wrong size of mask or wearing it inappropriately.

Protection factor = 100% - in leakage - media penetration  – defects - donning

Here is an example of a good mask versus a surgical mask with a cloth mask over it.  

Mask Protection Factor %
Parameter	Single Good Mask	Double Mask
Perfect Protection Factor	100	100
In leakage	-5	-5
Penetration	-5	-5
defects	-1	-1
donning	-4	-9
Protection Factor	85	80

 

This protection factor can be a guide but with the qualification that it is just one tool and subject to many variables.  This is why a guidance hierarchy is needed.

 Appeal

Media flow resistance is an important measurement. But without taking into account the amount of filterable media in a mask, the consumer is lacking the comfort information he needs.  Comfort is also about distributing pressure points, using the right fabrics next to the skin, and other parameters. It involves the activities of the wearer. A soccer player has a different experience than a bus rider.

Appeal also includes attractiveness.  A woman dressing up for a celebration is going to rate attractiveness differently than an office worker or meat packer.

Some mask companies have extensive feedback from clients and can credibly claim a high level of appeal based on  comfort plus attractiveness. The guidance hierarchy can rely on the user experience to help rate “appeal”.

Cost

The terms single use and reusable are no longer valuable labels. Due to the shortage surgical masks are being worn longer during one use and then reused. N95 masks are being cleaned with H2O2 and used many times.

Many masks offered to the public are designed for more than 20 wearings without any filter changes.  Other masks have filter inserts.

The same mask used for virus protection can also be used for wildfire smoke protection where the main concern will be accumulation of particles in the media and increase in resistance.

As people become vaccinated the concerns will be reintroduction of variants, influenza, wildfires, air pollution protection, and pollens. Masks are likely to be worn fewer hours per week and therefore last longer.

The cost therefore needs to include

-          initial cost

-          life

o   use

o   deterioration of efficiency or fit over time

o   loss of appeal

Two factors affecting life are efficiency and media resistance. Electrostatically charged media will lose efficiency over time. However there are billions of HVAC filters with meltblown media which are expected to remain efficient over months. The other factor is particulate buildup.  Again HVAC filters are expected to last for months before pressure drop increases sufficiently for replacement.

The concerns about virus transmission from the mask surface are legitimate but have to be viewed in terms of viral load. If you have momentary exposure to the virus and it is captured on the mask exterior and you touch the filter area 10 hours later much of the virus will have been inactivated. If the mask sits out overnight, by the following morning even less of the virus would be active.

To put this in perspective the risk of transmission from the mask surface ranges from 0 to 5%.  With UV or H2O2 cleaning the risk might be 0%. By just avoiding touching the outer filter  surface the risk might be 2%. So when you have a total protection factor of 60 to 90% a few percent difference in mask surface transmission is not a major concern.

Attractiveness deteriorates with time. Lipstick and cosmetics on mask interiors are one problem.  Multicolored or black masks remain at the original attractiveness level for longer periods. 

The consumer does not need much advice on this since “beauty is in the eye of the beholder”.  He can make his own judgements.

It is desirable, necessary and practical to set up a guidance system which results in mask consumers being able to make choices based on  the amount of protection, appeal and cost per use. 

 

Rolling Stone Rates Reusable Masks

 

Rolling Stone states that they have receive a commission from rating masks. This is in contrast to Consumer Reports.  Nevertheless Rolling Stone can be a conduit for information on effective masks. Their readers will very soon be wanting to know about mask effectiveness. Here is the just published analysis which we believe needs to be revised greatly as the new ASTM standards are understood and public interest shifts.

There is no concrete filtration efficiency or fit data.  Some statements such as “meets CDC guidelines for 2 layers”, or “has efficient nanofiber media” or “has PM 2.5 filters” are ambiguous or even misleading.

 

Rolling Stone “According to the CDC, the most effective cloth masks have materials that follow these guidelines:

• Tightly woven fabrics, such as cotton and cotton blends
• Breathable
• Two or three fabric layers

That being said, always check the label of your mask, since some companies use custom fabric blends, especially to increase warmth during the winter, or wick moisture.

One of the most important factors is the seal of the mask itself. Your mask should fit tightly over your nose and mouth, not leaving any gaps that might allow viral particles to pass through. Look for a reusable face mask with adjustable ear straps, or masks with a tight cone shape that will fit the contour of the bridge of your nose. If your cloth mask doesn’t have adjustable straps, make sure it’s still form-fitting and won’t move around too much on your face.

You can also customize any reusable cloth mask you get to enhance the fit—there are flexible metal nose strips, or mask extenders, which will also have the added bonus of reducing how much your glasses fog up, if you wear them. Double-masking with a non-medical mask over a disposable medical mask is also a great way to have added layers of protection, combined with a tighter seal on your face.

The best cloth face coverings are also machine-washable or can at least be washed by hand. While they won’t hold up forever, they can still be worn dozens of times, and washing them will help prevent them from building up bacteria and germs on the surface.

With that advice in mind, Rolling Stone rounded up some of their top picks for reusable face masks that will stand up to frequent use.

 

 

1. är Small Logo Black Self-Cleaning Face Mask

 

Tested by our editors, we recommend this sleek and comfortable face covering as one of the best reusable masks on the market. Not only is är’s mask design as stylish as it gets, it checks all our boxes in terms of secure fit and protective coverage—each Nanofilter included in the mask comes with three layers (two layers non-woven material, one layer nanofiber) for maximum particle filtration, and the top has an aluminum nose strip that seals off any possible gaps. While you can’t just toss it in the washing machine, each Nanofilter lasts for up to 40 hours of continuous wear before needing to be replaced (the mask itself is machine-washable). The mask is also treated with a “ViralOff” coating, which the company says kills more bacteria, reducing the number of times you’ll have to clean it in between uses.

är Small Logo Black Self-cleaning Face Mask, available on Concept är $29.90

2. Cremöly Face Mask

Looking for an eco-friendly alternative to disposable masks? Each of Cremöly’s masks can be reused up to 60 times, and are designed with sustainable materials, including a layer made of natural latex that will only take six months to decompose, according to the site. They’re still super light and breathable, thanks to a skin-friendly cotton layer, as well as adjustable straps that will create a nice seal without feeling suffocating. Coming in a variety of colorful prints and designs, you can customize these environmentally-conscious masks to fit your personal style.

Mäskup Face Mask Olive Green, available at Cremöly $13.99

 

3. Brave New Look Protective Face Mask (with PM2.5 Filter)

 

Brave New Look’s CDC-approved non-medical masks are reusable and come with a set of fourPM2.5 filters, which are designed to capture tiny particles and contaminants in the air. Just slip one of the filters into the built-in pouch, and breath normally through the lightweight cotton and spandex blend. We recommend replacing the filter after one week, but the mask itself comes in a variety of colors and patterns, so you can chose one you won’t get bored of wearing every day.

Brave New Look Protective Face Mask With PM2.5 Filter, available at Brave New Look $80 $47.60

 

4. Outdoor Voices Adjustable Face Mask

 

These double-layered, breathable face masks come with adjustable straps, so you’ll never have to worry about a flimsy fit or touching your face unnecessarily to move it around. Made from an 86% Polyester and 14% Spandex blend, you can easily throw them in the wash, and even in your dryer on a low setting. If you’re worried about always having to run your machine, these masks come in a pack of five, so you can rotate which ones you wear

 

Outdoor Voices Adjustable Face Mask (5-pack), available at Outdoor Voices $28

 

5. Rag & Bone The Stealth Mask Pack

Rag & Bone’s Stealth Masks are made from lightweight, upcycled materials, but have a cotton lining if you’re worried about comfort. As with most other masks made from 100% cotton, it’s recommended that you wash this mask before you use it first, and after every use, although you’ll have to hand wash these. But it’s totally worth it, as the mask is super convenient, with adjustable elastic straps and a pouch to safely store it in if you’re on the go.

Rag & Bone Stealth Mask Pack (3-pack), available at Rag & Bone $55

 

6. Uniqlo Airism Mask

Airism has a washable, built-in filter, so you won’t have to constantly replace filters like some of our other masks on this list. For comfort at any size, Uniqlo offers three options (S, M, L) so you can get the best fit possible for a reusable mask. For outdoor activities, or hot summer days, this mask has a mesh layer that blocks out 90% of harmful UV rays so you won’t get a dreaded mask tan while out and about. Reviews have also said this mask is quick-drying, since the first layer of fabric is moisture-wicking, which makes it a good mask for running.

Airism Face Mask (3-pack), available at Uniqlo $14.90

 

7. The Tie Bar 5-Pack Cotton Solid Masks

You wouldn’t think that a company known for its neckties and dress shirts would be designing fashionable and modern cotton face masks. But the two-ply cotton masks have an additional layer of shirting fabric, so you can pair it with just about any outfit. They also come with a built-in wire and adjustable ear loops, for a fit that’s as comfortable as it is protective. Maintaining these stylish masks is a breeze, just machine wash them and lay flat to dry.

The Tie Bar Cotton Solid Masks (5-pack), available at Tie Bar $30

 

 

8. Bonobos Riviera Face Mask

The Riviera cloth mask from Bonobos is not only washable, but has an additional pouch where you can add in your own filter. For an extra boost in comfort too, the mask is designed with double layers of cotton fabric, and a contoured, pleated shape to make room for the nose and mouth. You won’t have to worry about a secure fit, as the mask has two straps that go around the head and neck as opposed to over the ears, so there won’t be any gaps to speak of.

Bonobos Riviera Face Mask (3-pack), available at Bonobos $25

 

9. Sheertex Everywhere Mask

In terms of functionality, Sheertex packs a lot into their reusable face mask—their propriety knit blend means the face covering is cooling, lightweight, and moisture-wicking. The strings are adjustable, which is a big bonus, but the Everywear mask also has a naturally curved shape with edges that will hug your face naturally and stay in place. What we like: while this is a non-medical mask, there’s a built-in pouch for disposable filters, so you get both total facial coverage and more advanced filtration, if you want it.

Sheertex Everywear Mask, available at Sheertex $30

 

 

10. Huckberry Merino Wool Face Mask

 

This mask may be made with layers of pillowy-soft Merino wool, but it can still retain its shape well after multiple machine washes. Triple-layered for comfort, Huckberry says Merino wool was also chosen for its “moisture-wicking, breathable, temperature-regulating, and odor-resistant” properties. You won’t be using your reusable mask during just one season, and this mask is a great year-round companion: it’ll stay dry in the summer, while keeping you warm and cozy during the winter months.

 

Huckberry Merino Wool Face Mask, available at Huckberry $12

 

11. Everlane The 100% Human Face Mask

 

One of our favorite machine-washable face masks, this lightweight 100% cotton mask from Everlane has a CDC-approved double layer design. With a five-pack of these chic masks from Everlane, you don’t have to wear the same design every day, but the stretchy lycra ear loops make any of them comfortable enough for all-day wear. For every five-pack of masks sold, the company is also donating 10% of sales to the ACLU.

Everlane The 100% Human Face Mask (5-Pack), available on Everlane $25