Puraka Masks - Frequently Asked Questions

Choosing a Mask

You have so many different kinds of masks! Which ones are right for me?

Good question! We are constantly innovating and improving our masks to meet our customers needs. Here is a size chart for our Essential Masks (all collections Organic, Seattle, and Designer), Pacific Masks, and Universal Masks. 


How long do the masks last?

Our masks are designed to last for at least 60 washing cycles, and are fully guaranteed for at least six months or 25 washing cycles. This guarantee requires you use a delicates bag if machine-washing or drying your mask. If your nose clip breaks, email customer support and we'll send you a new one along with instructions on replacing it. If your mask's ear straps snap or your mask tears during normal use during the first six months, let us know and we will either replace it or offer store credit in the amount of the original purchase.

Since cotton can be washed again and again (and actually gets more protective over time as it shrinks), you are 
guaranteed longterm protection with a single mask. Other brands may guarantee a high number of wash cycles, but many of them build filters into their masks, and this material significantly degrades with each wash. That's the benefit of having a filter pocket and replaceable filter inserts!



What makes a Puraka mask different from other masks?

Puraka Masks are cotton particulate masks with a special pocket for disposable PM2.5 Filters. We've designed them to offer you the best of both worlds: filtering capabilities significantly higher than most fabric masks, with far less inhalation resistance and discomfort than an N95 Respirator. And now that our Essential and Universal masks are tested to the new CDC-endorsed F3502 standards, Masks are a great choice for anyone looking for enhanced protection suitable for everyday use.

A Puraka Mask is not intended as a replacement for an N95 respirator, and there's a very good reason for this. N95 masks fit tightly against your face, forming an air-tight seal between your mouth & nose and the outside world. This provides a high degree of protection, but this also makes it significantly harder to breathe. For a medical professional who is frequently exposed to airborne virions, the extra protection might be worth the increased strain on her heart caused by the N95 respirator. For the rest of us, wearing an N95 mask during everyday activities is probably going to cause more harm than good.

On the other end of the spectrum are cloth face masks. The purpose of these masks is to decrease the chance that you will unknowingly spread the virus to others. This is a great reason to wear them, but most cloth masks do relatively little to protect you from airborne aerosols or harmful microscopic particulates in your environment.


How do Puraka's masks compare to surgical masks?

There are a number of differences between ASTM F2100 Surgical Masks and the F3502 PM2.5 Filter Masks made by Puraka, but the most important difference comes down to fit. The filtration efficiency test for any Puraka Mask accounts for how well the mask fits on the wearer, and this is also required by the F3502 standard. That means the filtration scores we publish consider real-world factors like leakage.

The filtration test for surgical masks only evaluates the fabric, without taking fit into account. Outside experts who have tested Level 3 masks that advertise filtration scores in excess of 90% have found real-world sub-micron filtration varies, with some F2100 Level 3 masks achieving as little as 11% and others getting up to 70% or more when accounting for fit. You can read more in our blog post on PM 2.5 Masks vs ASTM Surgical Masks for the full write-up.


People say we should be wearing two masks. What do you recommend?

The US Centers for Disease Control recommends not doubling up when your primary mask is rated F3502. Read the CDC's advice.

Another thing to remember is that we are all much more likely to make frequent adjustments to our masks when it is uncomfortable because too many layers are making it difficult to breathe, and these adjustments can be unsafe if they let in air at the wrong time. If you decide to add a surgical mask over your Puraka Mask, we strongly recommend taking a few minutes to walk around indoors while wearing both masks, going up and down steps if possible, and make sure you are comfortable with the breathing resistance before leaving your home.


Can masks and filters be worn immediately?

Because the masks are made of 100% natural cotton, with no powders or coating, they are comfortable and safe to wear right out of the package. However, after additional laboratory testing we now recommend washing your mask once prior to wearing it. This will increase the filtration ability of the fabric. Don't forget to place the filter inside after you have washed!


Do your masks protect against COVID-19?

Puraka's mask and disposable filter system were designed with a very specific goal: preventing the inhalation of airborne particulates, without putting unnecessary strain on your lungs. No mask is 100% effective at protecting from viral transmission, and any claim that a mask offers "total protection from the Coronavirus" is not based on real science.

Airborne virions like the Coronavirus about 120 nanometers across. The laboratory testing required by the F3502 standard measures filtration against particles only 65 nanometers across, considered the "most penetrating particle size". This is also the particle size our filters are tested to. Generally, as particles get bigger, they become easier to trap, which is why we test against the very smallest particulates.

For more on protection, visit our education page.


Will the mask and filters sufficiently protect from coughing / sneezing of others who are within a few feet proximity?

The mask protects others from you as much as they protect you from others. Because of the Coronavirus' uniquely long period of pre-symptomatic spread, unless you're fully vaccinated, the CDC recommends having a mask on anytime you are indoors or cannot physically distance outdoors. No mask will prevent the transmission of all germs, but a Puraka Mask is designed to maximize the protection available from a fabric mask without the discomfort and cost of disposable medical respirators.


What is the lifespan of the filters?

PM2.5 Filters will not lose their effectiveness, but the air resistance will increase over time as the non-woven fibers accumulate airborne particulates. The filter should always be removed as soon as it becomes noticeably more difficult to inhale. Generally, you should feel no difference until 16-24 hours of continuous use (about 1-2 weeks of casual use for daily activities). After that point, the resistance will begin to gradually build up as more particulates are trapped by the advanced spunbond fibers. If you are using the filter everyday in the workplace, we generally recommend replacing the filter at the end of a 40-hour week. For active jobs like shipping, manufacturing or other manual work, we recommend 2 filters per week.


Who tests Puraka filters?

Puraka relies on SGS to test, certify and verify that your filters exceed performance specifications. SGS is one of the world's leading inspection, verification, testing and certification companies. Most importantly, they host the test results themselves, so they can't be faked or manipulated.


Which direction do the filters go in?

Puraka's filters do not have a preferred direction and can be inserted either direction. If you are using a filter that is darker on one side, the darker side should be facing your mouth. Always wash your hands before and after handling the filter.

For more on how to wear your mask, watch this instructional video.


What goes into a PM 2.5 filter?

The outer layer of non-woven spun-bond polypropylene serves as a physical barrier for moisture and larger particulates, including particulates of activated carbon and melt-blown fibers that might detach from the filter material.

The activated carbon layer is also good for a few different purposes. It acts as a deodorant and natural anti-bacterial, so it keeps the mask fresher longer. It also has electrostatic properties which allow it to capture small particulates that can't be stopped by physical barriers.

The melt-blown filter media is the most important layer. The individual fibers are much smaller than the non-woven spun-bond. In addition to incredible mechanical filtration, the material also has electrostatic properties. That's why they use it for N95 respirators.

Visit our blog post on PM2.5 Filters to learn more.


Which masks have more of an electrostatic charge?

A PM2.5 Filter gives any mask an electrostatic charge. Our workplace line of masks has built-in batting, which has its own charge even without a filter.


Is there a difference in moisture collection in any of your masks?

The only difference may be with the Active Masks, which utilize an innovative “open pocket” design for the filter. The open pocket design reduces the amount of fabric you have to breathe through, which helps to minimize the moisture buildup, but it also makes it important to use a filter or a mask bracket to hold the more flexible active-mask cotton away from your face.


Is there a difference in density?

All of our masks are manufactured with a cotton weave between 100-125 threads-per-inch. This weave allows them to qualify as tightly-woven, while staying under the maximum airflow resistance defined in the F3502 specification.


How are contaminants cleared from batting?

Contaminants are only cleared from the batting by washing the mask. Select "Sizing & Care" in the menu above for washing instructions.


What's the difference between the Valved and seamless?

The rule of thumb is a valve mask is more comfortable for long-term use because the valve reduces the heat and moisture inside the mask. All valved masks still have a layer of cotton on the valve, so they can be used without a filter, but cannot be ASTM F3502 compliant and may not always meet CDC guidelines.

We generally recommend all customers use the seamless non-valved masks unless you are working an active job or otherwise need a slightly higher breathability.


Where are your masks manufactured?

Our masks are manufactured in Europe, China, and the United States.


Sizing & Care

What size mask is right for me?

Figuring out your mask size can be a little trickier than knowing your shirt and pant sizes, but we've done everything we can to make things simple, including always using adjustable ear straps to help you achieve the right level of fit. Click the "Find my size" button below for our best guess, or take a look at our sizing chart for detailed measurements. If you think you might be somewhere in the middle, we recommend selecting the larger size, then shrinking your mask according to the directions below.

Find my size


My mask is too big. How do I reduce the size of my mask?

All Puraka Masks are 100% cotton, and because we try to minimize pre-production processing as much as possible, our masks are NOT pre-shrunk. This means you can reduce the size of your mask by up to around 20% with the following steps:

  • Wash your mask in hot water, either in the machine with a delicates bag or by hand, just be careful not to scald yourself!
  • Check periodically throughout the drying cycle to make sure you don't over-shrink the mask
  • When your mask is the right size, change the dryer setting to very low heat or just air, then dry the rest of the way gently.

How should I wash my mask?

Visit our guide to caring for your Puraka Mask for complete washing instructions.

It's important to not touch the front of the mask. Always wash your hands before and after handling the mask.


How can I dry my mask?

The masks can be tumble dried as a delicate in a mesh bag on low or no heat. You can also let the masks air dry, laid out flat to minimize risk of damage.


Can I wash the filter?

PM2.5 filters can not be washed. We recommend replacing the filter when you wash the mask.


Are there other ways to clean the mask?

We do offer an ultraviolet-light disinfection box that uses “Type C” UV light designed to sterilize the front and back surfaces of the mask.

Learn more here.

Mask Sterilization

How does the SteraLight work?

The SteraLight is an ultraviolet disinfection device, used for surface sanitization of your masks, phones and other small objects using UVC Type-C light.


What are the dimensions of the SteraLight?

6.9in x 4.1in x 1.2in (175mm x 104mm x 30mm)


Will SteraLight disinfect the filters, too?

It will disinfect the surface of the filter, but it won't unclog them, so when they trap enough particulates it will become harder to breathe and the filters should be changed.


Was the original Steralight's 253.7 UV-C wavelength tested in an independent lab?

It was. We also performed secondary testing ourselves with UVC Dosimeters from American Ultraviolet.


Was the Second Generation Steralight tested in an independent lab?

It was tested by the Guangdong Detection Center of Microbiology. We also performed secondary testing ourselves with UVC Dosimeters from American Ultraviolet.


What improvements does the 2nd Generation SteraLight feature?

We changed the lights from diodes to mercury lamps, and placed a mirror along the top of the inner lid to help the light reach the mask more uniformly.


I think something might be wrong with my SteraLight. Can I get a replacement?

The SteraLights are warranted for a one-year period. Customers experiencing problems with their box can contact support@purakamasks.com for assistance.


Do you offer extended technical support for the SteraLight or send replacement parts?

We do not provide extended technical support for malfunctioning devices. If a device is malfunctioning, we will replace it free of charge within a 1-year period. Please contact support@purakamasks.com for assistance.

ASTM F3502

What is ASTM F3502?

Unlike respirators and surgical masks, masks worn to help prevent the spread of COVID-19 aren't measured against federal performance standards. According to the CDC, that lack of standardized testing and labeling left people with no way to compare face covering products to make informed decisions when choosing a face covering.

To solve this problem, ASTM International worked with the CDC's NIOSH division to develop a new Barrier Face Covering standard (F3502-21). To meet F3502 requirements, a BFC must be tested by an accredited laboratory to achieve minimum filtration efficiency and air flow performance scores.

Read more about the F3502 label.


Are Puraka's masks F3502 compliant?

We are pleased to announce that our Essential and Breathe Collections are fully compliant with F3502!

Our Universal Masks have been tested to F3502 standards by an accredited laboratory and passed the filtration requirements. The Crimson, Gray and Navy model exceeded the maximum breathing resistance by a small amount (still less than half the breathing resistance limit of a medical-grade respirator!). The Universal Black model meets both the filtration and breathability requirement.


What are the filtration and breathability scores?

Here's how our different masks scored during testing:

f3502 filtration score comparison chart



28% filtration sounds kind of low. Is it really safe to wear an Essential Mask without a filter?

The sub-micron efficiency testing uses particles considered "most penetrating", because they are the hardest to capture. They are also small... less than half the diameter of the coronavirus! According to aerosol experts, a mask with a 20% sub-micron score should capture 80% of particles in the 5 micron range. In other words, a mask that filters 28% in the sub-micron range will filter out a substantial majority of aerosolized particulates, and even more with a filter!


Is it safe to wear masks with a breathability score over 15mm?

The standard uses 15mm as the cutoff because this level of breathing resistance is not expected to require a pre-use medical evaluation for the general population. It's also significantly lower than the 35mm cutoff for a medical respirator.

According to the CDC, symptoms like headaches, shortness of breath, or lethargy are a sign that your mask might be causing excessive C02 buildup, especially if you wear it for more than an hour in an active setting.


Who conducted your F3502 testing? Are they accredited to conduct under ISO 17025 to conduct the test?

Puraka is proud to utilize Kinectrics Inc.'s fully-accredited North American laboratory for our F3502 sub-micron and breathability testing. Kinectrics' accreditation scope can be accessed here.

The F2101 bacterial filtration efficiency testing was performed by TUV SUD, a global leader in respirator certification. You can access their accreditation here.


How are the masks designed to reduce leakage?

The F3502 specification requires the manufacturer to perform a Product Design Analysis. The graphic below shows the different design elements intended to reduce leakage and achieve a comfortable fit.

Puraka Mask F3502 Product Design Analysis Leakage



Will the mask have the label on it when I buy it?

We are in the process of applying F3502-compliant labels to all of our warehoused masks. Just in case you receive a mask without a label, we will send you a digital copy of the label via email when you make a purchase. You can download the Essential ASTM F3502-21 label here or download our laboratory testing results here.


Where can I see your test results?

You can download the raw data for our F3502 testing results here.


Filter Subscriptions

When does my subscription order ship out each month?

Your bank account will be charged one month from the date of your original order date. In order to keep our customers safe and to ensure they arrive on time, we ship two weeks prior to the charge date. For example, if you placed an order on August 1, your account will be charged next on September 1, but your masks will ship out around August 18.


Why is the monthly fee for the six-month subscription higher than the 12 month subscription?

All new subscribers get a free SteraLight UV Box, Laundry Bag and two Universal Masks. Because the six month subscription requires a shorter commitment, we charge a few dollars more per month to compensate.


I signed up for the six month subscription bundle. If I don't cancel after 6 months, will my subscription fee decrease?

Yes, your subscription fee will go down! After the first six months, if you decide to remain a subscriber, your monthly fee will go down to the same lower rate as the subscribers who opted for the 12-month commitment. Please email support@purakamasks.com if you have any questions about your subscription.


Is there a shipping charge for subscription filters?

No, shipping is free. Puraka sends your replacement filters early to make sure they arrive at your home or business before or on your anniversary date. As a subscriber, you'll also get free shipping on any store orders of masks, filters or any accessory priced over $7.00!


What are the other benefits of being a subscriber?

In addition to monthly replacement filters, subscribers receive all of the following:

  1. Automatic 10% discount on all store orders
  2. Rewards points redeemable for at least two free masks, every six months!
  3. Exclusive discounts on new masks and other store products.

Where do we sign up?

You can sign up for a subscription here.


Is one person allowed to sign up for multiple separate subscriptions, each with the free twelve month UV sanitizer box promotion?

Yes. A customer may maintain up to four subscriptions. If you are interested in filter subscriptions for school or corporate use, please contact sales@purakamasks.com.


Can the item count on a subscription change month to month?

The number of filters can be changed once per month, subject to the 15-day notice requirement.


Are there any stipulations for how many or how few times I can change my filter amount or the address they get sent to?

No restrictions. We only ask that you limit the number of changes to once per month per subscription.


How do I know when my subscription renews?

Subscriptions renew monthly on the anniversary date of the order.


How are subscription customers invoiced?

Subscription customers are charged monthly via credit card. When the customer purchases the filter plan, the system creates two orders. The first order is a regular order that gets filled immediately. The second order is a recurring order. This order will automatically charge the customer every month, on the same day the original order was placed.


When can I terminate my subscription?

We offer options to subscribe for a minimum of 6 and 12 months. After that initial period you can cancel anytime. The only limit is the cancellation must be at least 15 days before your monthly billing date, since we ship your replacement filters early in order to guarantee on-time delivery.


How does a customer cancel their subscription?

Every subscriber has created an account to opt-in to a recurring subscription. There is an option to cancel a recurring order near the bottom of your account page. You can also email support@purakamasks.com with your cancellation request.


Store Policies

How long does it take to process and ship my order?

Orders placed before 11:30 PM Central Time will be dispatched within 1 business day, but usually will ship the same day. Shipping itself may take 1-4 business days, depending on how far you live from the fulfillment center shipping the order. These estimates do not include delays that the fulfillment and shipping company may encounter.


What shipping methods do you offer?

For domestic shipments, we offer free ground shipping on any order of two or more masks. Upgrading to USPS Priority / First Class (depending on the weight) is available for a $5 fee. USPS normally treats First Class packages the same as Priority Mail, and estimates a delivery speed of 1-3 business days for both options.


Can I do multi-product orders?

For multiple product orders, we will make every attempt to ship all items contained in that order at the same time. Products that are unavailable at the time of shipping will be shipped as they become available, unless you inform us otherwise. You will only be charged for products contained in a given shipment, plus any applicable shipping charges. You will only be charged for shipping at the rate quoted to you on your purchase receipt. The entirety of this shipping charge will be applied to the first product(s) shipped on a multiple shipment order.


Do you ship internationally?

We currently ship to Canada, Mexico, the United Kingdom, Ireland, Germany, France, Spain, Switzerland, Israel, the Netherlands and Australia. If you would like us to enable shipping to your country, send us an email. We'll make it work!

For more on our return policies, visit our Shipping & Returns page.