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Planning to travel to China or India?  Air pollution can be a real concern if you are traveling with kids to cities such as Beijing in China, or Delhi in India, because children’s lungs are more susceptive to the harmful effect of airborne particles call PM2.5.

Singapore based Totobobo Pte. Ltd. introduced a new pollution mask specially designed for women and children. The new “Petit” mask comes with an innovative system to ensure a good seal between the mask and the user’s face.

Water Mark Seal Check of Totobobo UNIFit system

Water Mark Seal Check of Totobobo UNIFit system

Quality of the face seal is essential for the effectiveness of protection against air pollution such as PM2.5. However, it is often overlooked due to lack of simple and accurate method to check the seal. A study of 1500 fit-tests of 500 N95 masks on 50 Chinese by Tongji Medical College,  Huazhong University of Science and Technology, China, discovered that over 90% failed the fit-test due to poor face seal. This suggests at consumer level, over 90% of the time, even a certified N95 mask may fail to provide the expected protection due to poor face  seal.

Totobobo UNIFit system addresses the important issue of face seal with “Check & Seal” approach: 

1) An easy and accurate method to check the face seal, called “Watermark Seal Check”.

2) A “ReShape” feature which allows the user to shape the mask to close any gaps identified by the Watermark Seal Check.

3) A “Cut to size” feature which allows user to trim the mask to fit small children, in case ReShape alone is not sufficient to close the gaps.

“In addition to better fit and better protection, the UNIFit system also results in more comfortable wearing mask.” said the inventor Francis Chu, who has 20 years professional experience in product design.

Woman wearing Petit mask

Woman wearing the Petit mask. One can easily check the seal through the transparent mask.

A boy wearing Petit mask (customised to size)

A boy wearing Petit mask (trimmed to size)

Compares with the original Totobobo mask, the Petit is smaller, softer and more comfortable. Early Petit mask tester, Miss Hu Xiao Fei from Beijing China,  commented in Weibo:

“When I put on the new Petit mask, I was amazed! It fits so well all around my face, there is nothing I can say. I just love it!”

It looks like this small mask is going to be a big hit!

There is nothing I can say, it fits so well and seal my face all around! Miss Hu Xiao Fei (胡笑非), Beijing China

There is nothing I can say, it fits so well and seal my face all around! Miss Hu Xiao Fei (胡笑非), Beijing China

More information about the Petit mask can be found from the official website: totobobo.com, or contact us here.


Totobobo Petit (kid)

The Petit is a smaller version of the original Totobobo mask and is specially designed for ladies and children with smaller face sizes. Similar to the original Totobobo mask, the Petit comes with many important features of the original Totobobo mask, including easy and reliable seal check, which is the world’s first.

What are the important features we keep in the new Totobobo Petit model?

– Water-mark seal-check (Water mark seal check)
– ReShape the mask with hot water or hair dryer , to optimise fit to individual
– Can be trimmed to fit smaller face sizes (sometimes down to three years old)
– Adjustable straps for security and comfort
– High performance filters, easy to breathe
– Essential packaging, minimum impact to environment

Totobobo Petit (lady)

While inheriting the advantage of the original Totobobo mask, the Petit added the following improvements:

– Smaller size, fits most female and teenagers without trimming
– Softer mask body, more comfortable
– More secure filter cap
– Bigger effective filter area, even less breathing resistance than previous
– Includes an adaptor to convert earloop to head strap

In terms of operation, nearly all user instruction are the same as previous, except how to remove and replace the filter. Here is a video showing how to do it:

How to remove the filter:

How to install new filter:

For readers from China, please click here


How long does the Totobobo filter last?

This is a frequently asked question, but there is no standard answer.

The simple answer:

Change the filters when the color of the filters changed to 50% grey as shown in the filter package, or

Change the filters after 2 weeks of starting using it, even if the color has not changed so much.

The long answer:

The effective duration of the filter is heavily dependant on environmental factors and usage patterns. For example:

– Where is the filter being used? Outdoors or indoors?

– Is the air pollution level very high when you use the filter?

– Are you using it all day long, or just during your commute?

– Are you using it for exercising, such as running or cycling, or while you are driving?

– Are you using it while handicrafting? such as wood turning?

– Is the user a big man, or a small child?

All the factors mentioned about can affect the effective duration of the filters. If you are a big guy use the filter mask outdoors for exercise, your filters will last a lot shorter than a small boy using the same filter mask mainly indoors.

Since it is not possible to give an accurate answer for the effective time duration, we instead suggest the following, for maximum protection:

1) Change the filters when they reach a 50% gray color (as shown in the filter package).

2) Maximum usage duration is 2 weeks since first use of the new pair of filters, even if they have not reached the 50% gray color.

You may ask, why 50% gray and not 40% or 60%? And why 2 weeks, not 4 weeks?

To be honest, we are also not sure! But we’ve done tests and we feel comfortable with the above recommendation, knowing that the filters are still sufficiently effective at 50% gray and after 2 weeks since first use.

Below is an experiment to find out the remaining effectiveness of a pair of filters after two weeks of use, after accumulating enough pollutant to turn it into a 50% gray.

50% grey filter matching the color on the filter package

50% gray filter matching the color on the filter package

Filter preparation:

1) Attach a pair of filters to a box fan, drawing air continuously through the filters until it changes to 50% gray (matching the picture on the filter package).

2) Insert the filter to a Totobobo mask, and ensure the watermark seal check shows the mask fits well on the user’s face.

Respirator test with 50% gray filters:

We then conduct an NIOSH standard fit test for N95 mask.

Test setup with TSI PortaCount Pro 8083 respirator fit tester

Test setup with TSI PortaCount Pro 8083 respirator fit tester

Test result:

The test result is a marginal pass (Fit-factor = 100) for NIOSH N95 standard. Converting this result to filtration efficiency as following:

Filtration Efficiency = (1- 1/Fit-factor)% = (1- 1/100)% = 99%

This is not as impressive as a new pair of filters which is usually able to achieve a Fit-factor of 130+ , but it still provides sufficient protection for pollutant protection purposes.

Test result, Fit-Factor = 100

Test result, Fit-factor = 100




The quality of protection against PM2.5 is highly depends on how well a mask is sealing your face. Through the transparent body of Totobobo mask, you are able to determine the quality of the seal by checking the “watermark”. If necessary, you can Reshape the mask to improve the seal. Below is a short video showing how to ReShape a mask by a hair dryer.

* Alternative: ReShape Totobobo mask with Hot and Cold water



Totobobo demo in Beijing and Shanghai

Swanport cafe in Soho Galaxy at Chaoyang, Beijing

Swanport cafe in Soho Galaxy at Chaoyang, Beijing

Muren of Totobobo Tmall share a presentation about PM2.5

Muren of Totobobo Tmall share a presentation about PM2.5

Francis shared his story about Totobobo mask

Francis shared his story about Totobobo mask, Robin from Totobobo Tmall is providing realtime translation

2014-09-16 Swanport Cafe, Chaoyang District, Beijing

The demo in Beijing was a great success on a Tuesday evening, thanks to Robin and Muren from Totobobo Beijing and the helpful staff from Swan Port Cafe. The session started off with a brief introduction of PM2.5 by Muren, he explained what PM2.5 is, and how it affects our health. Francis, the designer of Totobobo mask, shared how he came up with the idea of a customizable and reusable respirator mask out of the SARS crisis in 2003. The fit-test demo started after a short tea break.

What is “Fit-test”? Why it is important?

Fit-testing is a procedure to determine if a tight seal can be achieved when the user don a respirator mask. This is important because the quality of the seal affects the overall protection against PM2.5 and other airborne contamination. In fact, the NIOSH N95 standard requires a proper fit-test to be conducted before anyone starts using a respirator for the first time. During the fit-test, a particle counting instrument is used to accurately measure respirator fit by comparing the particle concentration in the surrounding air with the particle concentration inside the respirator. The ratio of these concentrations is called the Fit-factor (FF). For N95 mask, a minimum Fit-factor of 100 is required in order to pass the fit test.

Fit factor formular

Fit factor formular

TSI Portacount is the best fit-testing machine in the world. (US Army recently purchased 65 sets of the same TSI Portacount fit-tester http://itbriefing.net/modules.php?op=modload&name=News&file=article&sid=571559)

The working principle of the PortaCount 8083 is straight forward: there are two flexible tubes coming out of the machine, one is to draw the air and measure the concentration of particles inside the mask. The second tube is open ended and is used to measure the particle concentration in the surrounding area. The PortaCount fit-tester calculates the particle concentration inside and outside of the mask and report the ratio, or the Fit-factor, in realtime. The higher the Fit-factor, the better is the protection effect of the mask. With the Portacount machine, Francis was able to demonstrate quantitatively how the quality of the seal and the filters can have a great impact on the protection effectiveness of a respirator.

Preparing for the test

Francis exchange ideas with the VIPs.

Francis exchange ideas with the VIPs.

Before the fit-test, a “Daily check” on the machine was performed to assure that the ambience air quality is suitable for the test and the machine is in proper operation condition. Amongst the audience, there were members from the China Consumer Association (中国消费者协会), National labor supplies Quality Supervision and Inspection Center (Beijing) 国家劳保用品质量监督检验中心(北京), Austria Embassy, TimeOut Beijing,  Aqicn.org and members of the public to monitor the entire process of the fit-test demo.

Fit test demo with PortaCount professional fit-tester

Faye testing Totobobo mask

Faye testing Totobobo mask

The perfect shape for Faye

The perfect shape for Faye

Fit-factor is only 3.3, the result of the cosmetic cotton pad is not convincing

Fit-factor is only 3.3, the result of the cosmetic cotton pad is not convincing

The first Fit-test of Totobobo mask was performed on Faye, a Chinese lady with a slender face shape. Francis first tested a pair of “fake filters” made of cosmetic cotton pad. The “fake filters” looks nearly the same as the original, but the resulting Fit-Factor is only 3.3 which means on a day with AQI 500, the cotton pad can ideally bring it down to 150, just not good enough. After changing into a pair of F96 filters, the Fit-factor shoot up to 150+. In AQI 500 day, ideally it can bring it down to 4-, better than the air you will get in Switzerland!

The Fit-factor shoot up to 150+ after changing into a pair of F96 filters

The Fit-factor shoot up to 150+ after changing into a pair of F96 filters

The second participant was a young girl (Guo Yao) with a fuller face. Francis first conduct the test with the same Totobobo mask without modification. The water-mark-method shown that the seal was not perfect and the initial result was relatively low (below 50). However, after Reshape the mask with a hair-dryer and after a good water-mark is obtained, the Fit-factor reported by the Portacount machine come up to 200+.

The perfect shape to fit  Guo Yao after ReShaping the mask

The perfect shape to fit Guo Yao after ReShaping the mask

Guo Yao received a new Totobobo mask from Sharon, Managing Director of Totobobo mask.

Guo Yao received a new Totobobo mask from Sharon, Managing Director of Totobobo mask.

Francis using the "Water-mark" method to predict the fitting of the mask

Francis using the “Water-mark” method to predict the fitting of the mask

Francis also demonstrated the effect of good and poor seal, by the “water mark method”. He applied a bit of water around the nose bridge area. When the matt color mask surface touching the wet skin, it changes to transparent (water-mark).

Barbara testing Totobobo mask

Barbara testing Totobobo mask

The third participant was Barbara Grosse from the Austria Embassy. It took Francis few rounds of ReShaping the mask in order to obtain a good water-mark seal. The final Fit-factor was also in the range of 150~200+. All three ladies passed with a clear margin from the minimum requirement of 100 (for N95 mask).

Fit-test demo based on only three users is obviously not statistically sound. However, we have done this nearly a hundred times privately and this is the first time we perform the fit-test in front of a public group.

After Beijing, we went to Shanghai ArtBike to conduct another fit-test demo with their customers. We came to similar observation as in Beijing.

Fit-test at ArtBike, Shanghai

Fit-test at ArtBike, Shanghai


Some interesting facts we can draw from all the fit-tests:

1. Totobobo mask can be ReShaped to fit a wide range of face shapes.

  • The same Totobobo mask was used through out the fitting on all three ladies, with significantly different face shapes and all managed to obtain high Fit-factors above 150.
  • Many more fit-tests on different users shows the ReShape function can be applied to a wide range of users.

2. The “Water mark” method is reliable to help ensure face fit and protection.

  • There was a strong correlation between the water-mark-method and the PortaCount results
  • When the water-mark method showed the seal was not perfect, the corresponding Fit-factor dropped  to below 50 and sometimes down to single digit value.
  • When a clear water mark was formed around the nose bridge and the face, the corresponding Fit-factor shot up to 150+

3. Overall protection against PM2.5 require good quality filter AND a good face-mask seal

  • When cosmetic cotton pad is used in place of the Totobobo filters, the Fit-factor dropped to only 3.3.
  • When the water-mark shows there is a leak between the mask and the face, the Fit-factor dropped to below 50 and sometime single digit.
  • The resulting Fit-factor is consistently good (150+) when Totobobo filter is used and the water mark result is positive.

Above points 1&2 are the strengths and the weaknesses of Totobobo mask, ReShape (and cutting) makes Totobobo mask the most versatile solution to fit a wide range of users, including children and adult. But ReShaping and cutting the mask is more complicated than bending a metal nose clip. With the “Water mark” fit-test method, you can be sure that when the water mark seal up your nose and mouth, the mask is giving you high level of protection. In contrary, ensuring face-seal is much more tricky for many popular masks on the market, as a detail research concluded by Tongji Medical College (Huazhong University of Science and Technology, Wuhan, China) suggested: Fitting Characteristics of N95 Filtering-Facepiece Respirators Used Widely in China . 8 out of 10 popular mask can only fit less than 10% of the 54 Chinese test subjects.

On the other hand, these two features are the limiting factors for Totobobo mask to gain certification approval. It is confirmed that the current testing protocol does not allow  mask samples to be reshaped,  cut, or perform a water-mark check before the fit. These may well be the reasons why Totobobo mask did not perform well in the published review of 37 masks by Chinese Consumer Association earlier this year. Obtaining the certification is an important step for marketing purposes, but for now we put our focus on the practical protection that can be measured by the professional fit-testing machine (PortaCount 8083).


Related links:

Beijing TimeOut

Totobobo Fit-test demo on Weibo (1)

Totobobo Fit-test demo on Weibo (2)

Testing Totobobo mask with Portacount 8083 (video of entire process)

How to ReShape Totobobo mask?



Totobobo demo in Beijing and Shanghai

Next week Tuesday (2014/09/16 to 18) I will be conducting life demo of customizing the Totobobo mask to fit individual users in Beijing and Shanghai. Here is a quick preview of what I intended to share:

The essential factors to determine protection against PM2.5 is:

  • (1) if a tight fit can be achieved between the respirator mask and the user’s face (mask-to-face seal)
  • (2) the quality of the filter
  • – Quality of filter can be achieved by technology and tested in laboratory
    – Quality of mask-to-face seal is the biggest issue for ensuring the protection for individual, because each individual is different

  • Fit-testing is a process to determine the quality of the face-to-mask seal for individual. This is essential because the protection against PM 2.5 is hugely affected by the quality of the seal.
  • Totobobo special approach: (1) ReShape or trim to fit most people, (2) Easy fit-check through the transparent mask
  • To validate our approach, we sent Totobobo mask to Prince of Wales Hospital in Hong Kong for fit-test. The resulting Fit-Factor is 135, which is better than the minimum requirement for N95 mask.
  • For normal N95 mask, a proper fit-test is necessary during the first use by a new user. This is to determine if a good seal is achievable.
  • – if a good seal is not achievable, the user has to choose a different mask
    – In case of Totobobo, if a good seal is not achievable (by see-through method), the mask can be ReShape or cut smaller to get a better fit

    All those who participated in the demo fit-test will get a free, customized Totobobo mask!
    email us as totobobomask(at)gmail.com if you are interested to join.


    Martie’s Totobobo filter in London

    Martie use her Totobobo mask for cycling in London traffic

    Martie use her Totobobo mask for cycling in London traffic (Southampton Row, London)

    Why do you choose cycling to work?

    I realised cycling is a cheaper, more reliable and (even) enjoyable mode of transport compared to the unreliable, overcrowded & expensive public transport. I’m least interested in cycling sports, but I’m glad that I made the decision to cycle for my everyday transport.

    Adding all the bicycle-related cost (bike, locks, mask, clothes etc. altogether) is equivalent of buying a 4-month travel ticket in London. Even including maintenance cost, I’m financially better-off cycling than using public transport.

    Another factor is reliability. Cycling may take a bit longer and require more physical effort, but at least its duration is predictable. Commuting on a public transport is always full of confusion and frustration due to unreliable service and overcrowding. But once I started cycling, to my surprise the whole set of travel-related stress has disappeared and I discovered happier me.

    When I started cycling I was scared my socks off for the first 2-3 months, but if you take it as a small adventure for the first time and repeat the route carefully, the nervous excitement will wear off and cycling will become everyday activity after a while.

    To cycle safely amongst large vehicles, you just need to know the DOs and DON’Ts around those vehicles. As long as you adhere to it, those big guys won’t harm you. If you respect other general traffic rules, the motorists will respect your presence in return. You cycle alone but you share the space with everyone else.

    How is your experience of using Totobobo mask in London?

    Martie at Kingsway, London, WC2B

    Martie at Kingsway, London, WC2B

    filters facing outside of the mask.

    Totobobo mask after cycling in London about a week, the distance covered is approx 80km.

    I use Totobobo mask all the time as I cycle everywhere in London.

    Since I began commuting to the centre of London where traffic pollution is worst, I started using double 96% filter for my mask.

    With single filter I get discomfort in my throat after every journey because of the heavy traffic, but with double filter I can clearly feel the improvement. Previously I keep producing small amount of sputum for a couple of hours after every journey, whereas with double filter, I don’t get that ‘ahem…ahem, ahem…’ phase, virtually none.

    Obviously using double filter limits my inhalation, but I’m happy to take this trade-off for greatly reducing discomfort caused by pollution.

    I have been using double filter nearly every day for about 4 months, and so far there’s no lasting respiratory impact, only short period of breathlessness immediately after a journey.

    filters facing outside of the mask.

    filters facing outside of the mask.

    With the mask, I’m more willing to travel longer distance without worrying about the level of pollution, it also allows me to cycle safely as I’m not compelled to move away from the rear of a vehicle when it is unsafe to do so.

    I do intensive exercise regularly so I know my respiration capacity is stronger than the average person, but I’m also aware that there might be a long term negative impact of having double filter.

    (Note: Double layer of filter may cause discomfort and can be damaging for special group of user. Consult your doctor before applying double filter on your mask.)

    Have you try other brands (of mask) before?

    No, but other products didn’t look so air-tight while Totobobo taking less space to carry around. Other product looked either too elaborate or too flimsy. Totobobo seemed to me hitting the right balance.

    The rather clinical look of the mask sometimes raise eyebrows, but I think it’s just an outcome of that famous principle ‘form follows function’.


    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

    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) http://tinyurl.com/totobobo-test

    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

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