Earth Filter Review- Universal Mask Filter With 99% Filtration

Re-Mask Filter Technology

With massive mask shortages taking place all around the world currently, many are turning to creative solutions for filtering their air. While these solutions are better than nothing, they are often far from proper filters that are designed for particle filtration. 

In times like this, many people, companies and organisations are looking for alternatives that can provide adequate protection from fine particles that are not only easy to produce but also cheap and easy to access. 

Re-Mask is a new company that is based in Hong Kong. I recently reviewed their mask products and found them to be very wearable masks that have achieved good third-party filtration results. 

Re-Mask is soon going to launch another product though, and that is the Earth Filter. This filter is designed to be a solution to the global mask shortages and to provide any mask with higher filtration efficiency.

This post contains affiliate links. For more information, please refer to my affiliate disclaimer. I was sent a product for review, but the article is not sponsored. All opinions expressed in this post are my honest thoughts. I only recommend products that I truly believe in.

Information on this blog is for informational purposes only. Readers are encouraged to confirm the information herein with other sources. Furthermore, this information is not intended to replace medical advice from professionals. This website assumes no responsibility for the accuracy of information and information is subject to change without notice. Devices mentioned on this website are not medical devices and do not guarantee protection.

Purchase Earth Filter here!

Earth Filter Concept

Earth Filter Technology

The idea behind Earth Filter is that there needs to be a universal filter that anyone can use. Whether you have a scarf, surgical mask, or respirator, there should be a single filter that can be placed within these to provide further protection to the wearer. 

I think that the Earth Filter Kickstarter provides the best description of the issue: ‘Due to the shortage of surgical masks, a lot of us have bought fabric masks to protect ourselves from the current pandemic. The problems are fabric mask themselves, regardless of if they are cotton or polyester, they do not have the capability to filter small particles. On average, fabric masks can only filter up to 20% of the airborne particles in the air.

In plain words, fabric masks alone are not good enough. A filter is needed to add filtering capability to fabric masks. However, filters come in different sizes and shapes, which means you might need to pair a specific mask to a specific filter.’

In order to try and solve this issue, Earth Filter has been designed to fit inside a large range of masks and to meet high filtering standards. In this review of the Earth Filter, I want to investigate the filtration capabilities of the filter, the fit, and to also look into how it works with some of the other masks that I have. 

Purchase Earth Filter here!


Earth Filter

The Earth Filter has 5 layers including a carbon filter.

Earth Filter has recently been tested by Nelson Labs and has achieved high results. However, it is important to note that a filter can only filter the air that passes through it. That is to say, fit testing is very important for achieving the highest filtration efficacy. 

Since Earth Filter is only a filter, and not a mask itself, it is vital to make sure the filter is fitted correctly. While getting a perfect fit is near impossible, the Earth Filter will provide better protection than cloth masks and surgical masks when it is fitted well. 

For the best protection, use a mask that has a wire nose-piece or is tight-fitting with minimal leaks. I have found that the Earth Filter works (and fits) well in my MeoAir mask, Re-Mask and also in Gill Mask. While the filter fits many masks, those with a tight fit (that force the air to pass through the filter) will have far better results. 

Earth Filter 1

The filter itself has been tested to have ≥ 99.76% filtration at an MPPS of 0.3μm. This result instantly puts the filtration capabilities of the Earth Filter at a similar level to the TotoBobo mask, Cambridge Mask, Airinum Urban Air Mask 2 and many other popular reusable masks

At the same particle size (MPPS of 0.3μm) the Earth Filter was also found to be ≥ 97.3% effective at filtering bacterial particles and 99.9% effective at filtering viral particles. This means that when the filter is fitted correctly it is capable of filtering the vast majority of particles. 

Particle TypeParticleViralBacterial
Filtration %≥ 99.76%> 99.9%≥ 97.3%

All data used is from the Re-Mask Nelson Lab test results.

It is important to note that particles smaller than 0.3μm will be filtered more effectively. I often get asked how effective masks and respirators are against smaller particles – the answer is that they are very effective. While there are limited studies on nanoparticle filtration, down to 4nm N95 respirators have been found to provide more than 95% filtration (source).

The Earth Mask also features a carbon filter which is a welcome addition. These filters are designed to remove organic compounds by means of adsorption (not absorption!). While these filters aren’t effective against most non-organic compounds, they are useful at filtering pollutants such as benzene, toluene, xylene, oils and more (source).

Another benefit of carbon filters is that they are capable of filtering some odours. This means that when wearing the Earth Filter you should notice less smells – however, this only applies to some chemicals.

While some respirators have carbon filters within, the addition of such a filter still isn’t commonplace. Although this is a welcome addition, it is important to note that if you need protection from chemicals or gases a specialised respirator is essential. 

Purchase Earth Filter here!

Earth Filter in Masks

Re Mask Organic With Earth Filter

I tested the Earth Filter in a variety of different masks to see if the universal fit claim is true. While it won’t fit every mask, I did find that it fits well in a large variety of masks. Frankly, with the differences in mask sizes, I was impressed with how many masks the Earth Filter fit well. 

The only masks that the Earth Filter will not fit at all are those that require (larger), totally custom filters. For example, the fan-powered Koolmask that I recently reviewed uses a proprietary filter that is not only larger than Earth Filter but also a more unique (rounded) shape.

While the filter isn’t intended to be used inside masks that already have a filter, I first tried the Earth Filter within a Cambridge Mask and Vogmask. The filter was too large for both of these masks (they are both small size). I believe the filter would fit well in larger models of Vogmask and Cambridge Mask, however. 

I then tried the filter in the MeoAir Mask. This mask has interchangeable filters, and as such, it is a more likely scenario for using an Earth Filter. On my small-sized MeoAir Mask, the filter fits perfectly. Since the mask also has a good fit with a wire nose-piece, I found this to be perhaps the best fitting mask out of everything that I tried. 

Earth Filter in MeoAir mask

Of course, the filter also works well in Re-Mask’s masks – including the Re-Mask Sports. Although the Earth Filter is not designed to be used in these masks (they have their own filters), the Earth Filter fits well. On the large models, the filter was slightly too small, but it fits well on the smaller models. 

Afterwards, I tried the Aropec Mask. I thought this would be an interesting choice as the Aropec is an antiviral mask, but one that doesn’t have tested particle filtration capabilities. The filter fit well, however, it did move a bit during wear and this is something to be aware of. 

Earth Filter with Surgical Mask

The same goes for surgical masks and other cloth masks. If you have a tight-fitting cloth mask, the filter can fit well. However, I found that surgical masks were typically too loose (even when tightened and folded before wearing) for the filter. It tended to move a bit during wear, and it needed to be readjusted. 

Finally, I also tested the Earth Filter in some other respirators. The two that I tested were standard KN95 and KF94 variants. Although the filter is not intended to be used in masks that already have capable filters, I found that it fit well and needed little adjustment. The issue is that the breathing resistance was quite significant due to having two filters. 

Earth Filter in Aropec Mask

Typically, the Earth Filter should fit any medium to larger sized mask. It may be a struggle getting the Earth Filter to fit in smaller masks (such as S sizes from Cambridge Mask and Vogmask), however, it did fit in the majority of masks that I tested. 

It should also fit masks that require smaller filters. For example, the Gill Mask uses very small filters. The Earth Filter can easily be cut down to the correct size, and from experience, I was able to get two filters from each piece. Using a mask such as the Gill Mask also makes it far easier to make sure the filter is properly fitted.

Again, it is important to remember that the Earth Filter will not be fully effective unless it is fitted correctly. If you don’t have access to a well-fitting mask, the filter can provide some protection. However, a well-fitting respirator that the Earth Filter fits well will provide the best results. 

Purchase Earth Filter here!


Re Mask Casual Black

Earth Filter works well with Re-Mask

The Earth Filter is an innovative idea to reduce waste and to make filters more widely accessible. While the idea of a universal filter may not be new, the Earth Filter is the best fitting filter that I have tested to date. 

The filter has been tested and proven to provide high filtering efficiencies. It performs similarly or better than many of the other reusable masks on the market and it is capable of fitting in many masks on the market. 

For the best results with the filter, I would recommend using it in a mask that it fits in well. From my experience, the Re-Mask Casual and MeoAir Mask fit the filter best and provide a good overall fit. 

If you currently only have access to surgical masks, cloth masks, or other less effective masks, then the Earth Filter is a great way to add some extra filtration capabilities. Not only is adding the filter easy, but it’s also cheap and more environmentally friendly than constantly disposing of masks.

Earth Filter FAQ

Has Earth Filter Been Third-Party Tested?

Yes, the filter has been tested by Nelson Labs to achieve the filtration specifications mentioned here.

Does Earth Filter Fit Every Mask?

Earth Filter does not fit in every mask, however, it does fit in a large variety of masks. Smaller masks may be too small for the filter, but most larger masks will house the filter well.

What Does Earth Filter, Filter?

Earth Filter is capable of filtering viral, bacterial and fine particles. It is capable of filtering all of these to > 97% efficiency. However, the filter must be fitted correctly for this efficiency.

What Masks Can I Put Earth Filter In?

You can put Earth Filter in nearly every larger size mask on the market. Some masks with unique dimensions may not fit the filter, but the majority of standard sized masks will.

11 thoughts on “Earth Filter Review- Universal Mask Filter With 99% Filtration”

    1. Hello James,

      Great question! Compared to the MeoAir filter I found this to be a bit more difficult to breathe through. However, it was not as big of a difference as I would have expected. With the significant price difference between the two, I would personally stick to the Earth Filter in most cases.

      1. Surely the Earth Filter costs a lot more than Meo?

        A pack of 10 Earth Filters is USD26, so USD2.60 per filter. They last 48 hours, so about 7-8 days at 6-7 hours per day. So, USD0.37 per day.

        The Meo filters are NZD57 for 18 filters (their offer of buy 3 packs of three filters and get another 3 packs free). That’s NZD3.16 per filter, which is about USD2.11. The Meo filter lasts 2-3 weeks, so let’s conservatively say USD0.15 per day.

        Both calculations exclude postage, so maybe that would narrow the gap in some cases, depending on volume and destination.

        1. I did my math a little bit differently.

          Firstly, the MeoAir filter and Earth Filter have almost identical lifespans (MeoAir – 50 hours, Earth Filter – 48 hours). Of course, the exact lifespan depends on the AQI, frequency of use, etc. However, both filters should have very similar usage periods.

          Further, it really depends on how many you buy. If you are comparing the 18 filters of MeoAir, then I think it’s best to compare to the closest Earth Filter pack (20 filters for $42 USD). The 18 MeoAir filters cost $38 USD, which is very similar (20 EF for $42 or 18 MeoAir for $38).

          You do raise a good point though – in some cases (perhaps the majority of them), MeoAir filters are cheaper. The 10 + 15 (75 filters) for $190 NZD is also a great deal for anyone looking for bulk purchases.

          1. Ah, I was just going by the only offer they show on the website home page. I missed that they had other bundles on another page that are better value, which makes the price closer. The cheapest might come down to postage costs and what volume you are up for ordering.

          2. No problem! I actually didn’t notice the number of MeoAir filter options avaliable either – your comment made me go back and look through them. I am actually surprised with how affordable they are. But yes, I think shipping is a big factor. It seems that MeoAir shipping prices are very high.

        2. I just realised I was comparing the MeoLite filter. The Reusable filter has around double this usage period. In this case, yes, MeoAir would be cheaper.

  1. Since the Earth filter fits both the Re-Mask Casual and the MeoAir mask (not Meo Lite?), would it be correct to assume that the Meo Helix filter (again, not Lite) will fit the Re-Mask Casual? I am looking for a comfortable mask that will fit the Meo Helix filters, but this is hard to do when nobody gives mask or filter dimensions. Thanks!

    1. Hello Rodrigo, thank you for your question!

      I actually meant to say Meo Lite, that is my mistake. Unfortunately, I can’t give a certain answer to your question as I have never used the Meo Helix filters (I have only used the Lite filters). If I had to make a guess though, looking at the size chart (I believe the Helix Filter to be a bit bigger than the Lite) it would be a similar size to the Earth Filter. Therefore, I believe the Re-Mask Casual should fit the Helix Filter, especially the larger sizes.

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