Latest filter test report from Nelson Labs

Recently we received the final test report regarding F96 and F94 filters from Nelson Labs. The result summary (and link to the pdf):

F96 filter
Latex Particle Challenge Final report
Test particle size: 0.1μm
Filtration efficiency %: 99.86

F96 filter
Bacterial Filtration Efficiency.
Test particle size: 3 μm
Delta P: 11.4 Pa/cm2
Flow rate: 8 L/min
Filtration efficiency %: 99.9*

F96 filter
Viral Filtration Efficiency (VFE) Final report
Test particle size: 3 μm
Filtration efficiency %: 99.9*

F94 filter
Latex Particle Challenge Final report
Test particle size: 0.1μm
Filtration efficiency %: 99.71


Fit testing Totobobo mask with 5.5 years old

Happy Lucas wearing a well fitted Totobobo mask

Happy Lucas wearing a well fitted Totobobo mask

Conducting a fit-test with Lucas

Conducting a fit-test with Lucas

Lucas is the youngest fit-tester ever tested by our Portacount Pro fit-tester machine so far!

Lucas was born in the year of rat 2008, making him 5 years 6 months old when he visited us for a fit-test. Not long ago Yixuan, Lucas’ mother, send us a photo of Lucas wearing a Totobobo mask and explained that she couldn’t get it to fit him perfect enough. After checking the photo it is obvious that the mask was too big for Lucas. I offered to to conduct a fit-test help to customize the mask for the little boy.

At first the mask was too big for Lucas..

Help! Lucas’ Totobobo mask is way too big. Large gaps can be seen below the chin and around the nose bridge. Photo credit: Yixuan

Lucas’ mum told us he is a very active boy and makes friends easily with both adults and peers. It was fun to have Lucas since he is very playful and active. However the fit-test part was a bit challenging since Lucas has to keep still and perform certain specific action, such as deep breathing, moving the head steadily side to side and up-and-down. The most difficult action turn out to be “breathing normally”, (that sounds so boring for Lucas) and the easiest was “Talking loudly”.

Optimized Totobobo mask after the fit test

Optimized Totobobo mask after the fit test

We were unable to obtain an uninterrupted routine to pass overall “Fit-factor” of 100. On the other hand, although the result during “Normal breathing” was a poor 20, incidental results of over 100 means that it is possible for Totobobo mask to achieve N95 level performance on a 5 and a half years old. For example, during the task “Head side to side” the fit factor was 107, and another task “Head Up and Down” the fit factor was beyond 200!

Partial result during the fit test

Partial result during the fit test


How do we test Totobobo mask?

We have not yet figure out what were the causes of the relatively poor results from the CCA (China Consumer Association) test report last month. What we can do now is to share how we conduct our own test to ensure a high level of protection is achievable with Totobobo mask. Even Though Totobobo mask is not a certified N95 mask, we make use of an OSHA-compliant fit-tester called PortaCount® Pro+, which is manufactured by TSI in USA.

由于资料不足我们还没法弄清楚为什么Totobobo在上月中国消费者协会(CCA)的测试报告中表现较差。但我们可以公开我们是如何测试Totobobo口罩,以确定它对PM2.5的高度防护作用。Totobobo不是一个N95认证的口罩,但我们采用符合OSHA标准,由美国TSI公司制造的定量测试仪,PortaCount® Pro+。

Theory of operation of a PortaCount Pro + Image credit: TSI

The PortaCount® Respirator Fit Tester works by measuring the concentration of microscopic dust particles in the ambient air and then measuring the concentration of those dust particles that leak into the respirator. The ratio of these two concentrations is called the fit Factor.

PortaCount® Pro+ 的工作原理为何?它是如何进行口罩测试仪工作?
PortaCount® Pro+ 有两根导管,一根通往口罩测量口罩内的微小颗粒的浓度。另外一根在口罩外测量周围空气的微小颗粒的浓度。PortaCount® Pro+ 根据这两个浓度的比值计算出总保护率(Fit Factor),这包括过滤效率和泄漏性.

A fit factor is a measure of how well a particular face piece seals against a person’s face. It is expressed as a ratio of the concentration of challenge aerosol outside a respirator to the concentration of aerosol that leaks into the respirator through the face seal. A fit factor of 100 means the air inside the mask is 100 times cleaner than the air outside.

什么是总保护率-Fit Factor?
总保护率-Fit Factor是指一个口罩对某一个使用者人的总体保护程度。以口罩内外空气中两个颗粒的浓度的比值计算。总保护率-Fit Factor =100 即是表示面罩内的空气比外面的空气清洁器100倍。N95口罩的总保护率-Fit Factor必虽达到100。

The PortaCount® Pro is a Quantitative fit tester (QNFT). QNFT is a better test because it eliminates the subjectivity of QLFT. A quantitative fit test is not affected by the person’s sense of smell, taste or sensitivity to irritant chemicals. One of the most appreciated aspects of QNFT is that the test subject cannot deceive the test operator, as often happens with QLFT.

PortaCount® Pro+是一款定量测试仪。 定量测试比定性测试更好,因为它消除了定性测试中会影晌结果的一些主观因素。例如受试者的嗅觉,味觉或对刺激性化学品的敏感度。在定量测试中测试受试者不可能欺骗测试仪。

Below is a 9 minutes video showing the entire process of a Quantitative fit test. The final result shows the Totobobo mask with a pair of F96 filters is able to reduce ambient particles by 142 times (Video @ 8:48), or a fit-factor of 142.

以下是一段9分钟的视频显示PortaCount® Pro+定量测试的全个过程。最终的结果显示Totobobo口罩可以提供142的总保护率(Fit Factor)。面罩内的空气比外面的空气清洁器142倍,即总过滤效率=1-1/142=99.3%。(视频@8:48)

Fit-test-Totobobo Mask with TSI Portacount Pro 8038 from Francis Chu on Vimeo.

Intro to Quantitative Fit Testing (TSI)

Totobobo mask in NIOSH site for “No Fit Test Respirator”

Clearly a Better Way to Check for Safety


CCA report: Totobobo mask performs not as good as $1 disposable mask?

2014-03-21 Beijing, China
China Consumer’s Association (CCA) published a major test report of 37 types of anti-pollution masks purchased from open market in China. These includes sources from both physical shops and online stores. The test was conducted according to Chinese standard GB2626-2006 《呼吸防护用品自吸过滤式防颗粒物呼吸器》, or 《Particulate Filtering Facepiece Respirators》. Majority of the test samples are disposable respirator, a few cloth mask (permeable material) with exchangeable filters. Only Totobobo mask is “rubber mask” (non permeable material) with exchangeable filters. According to the results, at a rating from poor (1 star, to best, 5 stars) Totobobo mask rated 3.5 stars for filtration efficiency, 4 stars for breathing resistance and “POOR” for face fit. This result compares to a few of the much cheaper disposable mask (e.g. Maskin 61750) is not impressive at all.

Link to the CCA test result here:

We were quite surprised by the poor result because there is a big differences from an earlier study done in the Prince of Wales hospital, Chinese University in Hong Kong. That study compared the performance of Totobobo mask against several N95 masks previously fit tested. The results shown that Totobobo mask was able to achieve reduction of airborne particles by 132 fold while those previously fitted 3M masks were able to achieve 193 fold of reduction. In terms of comfort 65% of subjects preferred the Totobobo mask
over the N95 masks (1860, 1860s 3M).

Link to the hospital test in Hong Kong:

Since there is a large gap between the two tests, we are now trying to find out more information about the CCA test, for example what kind of tests have been performed on the mask, and how it was conducted. Perhaps the reason will be more clear about our investigation. We will update this post at we find out more.

If you have any idea/theory to explain this performance gaps, please leave a comment below.


How to improve the locking power of the new filter cap?

How to improve the locking of the filter cap?
The filter cap can be reshaped to improve the locking power.
Follow the following steps :


How to improve locking power of Totobobo filter cap?


Totobobo on WSJ and CCTV

Totobobo mask was recently featured in The Wall Street Journal and CCTV. Below are the links:

Totobobo featured in The Wall Street Journal!8947A308-3A68-4689-AA5E-B741B9FF5927

Totobobo mask featured in CCTV


Nanjing University experiment with used Totobobo filters

Nanjing University Totobobo filter experiment

Would you like swop your used TOTOBOBO filters with new one?
We are helping a research group in Nanjing University to study the harmful material in the filter. Two sub-groups will be analysing the organic material as well as the heavy metal trapped in the used filters.
If you are using Totobobo mask in China, this is your chance to help.
What we need you to do is to send your used filter to Totobobo China in Beijing, along with the following details:

Details of used filter pair (example)
Date: 2013-12-12 ~ 2013-12-14
Duration: 7 hours
Location: Beijing, Haiding
PM2.5 range: 200 ~ 300

The research team will publish the result at the end of the study. To support this meaningful study, we will issue 60 pairs of F96 filter to swop with the first 60 pairs of useful filter samples.

Below is more detail instruction in Chinese:
Nanjing University Totobobo filter experiment


There is a large gap around the filter holder! (2014 design)

Some user feedback that the filter holder of the 2014 new design is not as tightly seal as the old design. There is a large gap around the filter holder and the filter inside is clearly exposed. (pic. 1)

Does this gap cause a problem with the seal?

Does this gap cause a problem with the seal?

First the large gap around the filter holder is our design intent. It is designed to allow more air to go through the filter. More air opening means lower resistance and easier breathing. This is an important benefit relates to the comfort of mask wearing.
Now, does this large gap also indicates the new 2014 model is less protective?
Certainly NOT. To understand, you need to check the inside of the mask (pic. 2) Here you can see clearly, all the air has to go through the opening. The seal is valid, as long as the filter makes good contact with the edge of the opening.

The seal is good , as long as the inside of the filter is properly fitted.

The seal is good , as long as the inside of the filter is properly fitted.

To demonstrate the above is true, we use a TSI PortaCount device to perform a fit test of a user using the 2014 new design. The overall fit-factor in this case is 165, clearly above the pass rating of 100.

Fit test result from one of the 2014 design users.

Fit test result from one of the 2014 design users.


A nice little review of Totobobo mask

By Electric Bike Review

If you’ve ever been riding in traffic and wondered “is this car exhaust bad for me?” you’re not alone… and yes, it is. I went on a search for a good air pollution mask that would work with my cycling glasses and helmet and found a few good options. I even invented one of my own. My favorite is the Totobobo from Singapore.


2014 new design

Some of you may have received our new design (2014) ahead of this official announcement.
The 2014 new design of Totobobo mask has improve the design based on feedbacks from our supportive users.

Some of you told us the previous filter cap was not easy to use and a few broke the filter cap while trying to open it. Also some lost the filter cap and need to purchase the replacement.

We have improved the design of the filter cap, it is now attached to the mask (never lost it again!) and it is easier to operate.
The mask body material has been improved to ensure 100% support of the ReShape feature.

The key improvements:
- Filter cap integrated with the mask body, no more missing caps.
- Easier operation to lock the filter cap, no more broken cap.
- Multi-directional filtering – even more easy to breath!
- Improved formulation for the mask body, 100% support the unique ReShape feature.

An important design principle is ECO friendliness and sustainability. While moving over to the new 2014 design you should not throw away the old parts. All filters, head-strap and earloop straps are compatible with the old design. This is a running change so we will be using the same code name (TTO, TTLe, TTSC and TTSCe) as before. During this couple of months some of you may received the original design while others may receive the new design. Here are a few photos of the new design (2014) for your reference:

Totobobo 2014 new design