Chinese industrial filters

We need more information
This article is a stub.
You can help Gas Mask and Respirator Wiki by expanding it and adding more information to it.

Hold up! Under construction
This article or section is currently under construction and is in an unfinished state. If there is an urgent need for information about this topic, comment at the bottom of this page with a question.

The neutrality of this article is disputed
Articles should be written from a neutral point of view, and should not reflect the views of authors.

Generally, Chinese industrial filters have GOST 8762-75 compliant threads, so it is not "normalised threaded".
They are manufactured by many different manufacturers, most of which produces masks too.
They are often dubbed "TF-1 filters" for oversimplication which sometimes leads to confusion.
The earlier ones really were simply named "TF-1 filters", which is intended for TF-1 masks.
Later ones have different model names under different manufacturers.
Note that the GB 2890-1995 standard uses colour code while the GB 2890-2009 standard uses colour code and letter identifier code.
The classification standard of GB 2890-2009 is the first Chinese standard that begins to start unison of standardization with the international ABEK system
List of standards over the years:

GB 2890-1982 (superseded)
GB 2890-1995 (superseded)
GB 2890-2009 (superseded)
GB 2890-2022 (current enforcement)

Footnote: Ichigo brand filters are under Yihu brand, which are made by Shandong China Industry Protection Technology Co., Ltd.

NOTE: The research on this topic is ongoing. Please be patience. Any new information which are NOT based on speculations would be helpful on this research.

Classification of the filters[]

Levels[]

A common theme among Chinese filters are the use of "levels" to describe the type/size of filter. A lot of machine translation will call refer to them as primary/secondary/tertiary but it's better to think of it as closer to a sizing or protection scheme. Keep in mind that these keywords are used domestically, and won't work if you're searching in English on an English website.

Level 1: This is usually used to refer to the "pad"-like filters, similar to those used in 3M masks.

Level 2: These are the conventional cylindrical filters that screw directly into a mask.

Level 3: Level 3 filters are the "coffee-can" style long filters that one'd typically wear on a belt.

Chemical classification[]

Numbering of filter	GB2890-2009 letter identifier	GB2890-1995 colour code	GB2890-2009 colour code	Protection against
No.3	A	Brown	Brown	Organic gases or vapours
No.1	B	Green	Grey	Inorganic gases or vapours
No.7	E	Yellow	Yellow	Acidic gases or vapours
No.4	K	Grey	Green	Ammonia and its derivatives
No.5	CO	White	White	Carbon monoxide
No.8	H2S or H₂S	Blue	Blue	Hydrogen sulfide
(still unknown/not understood clearly)	P	(still unknown/not understood clearly)	Pink or no colour	Particulate matter
(still unknown/not understood clearly)	(still unknown/not understood clearly)	(still unknown/not understood clearly)	Orange	Radioactive iodines
No.6	Hg	Black	Red	Mercury
No.9	T	Green	Purple	Formaldehyde

Obtaining[]

It's quite difficult to find specifically Chinese filters since, unlike soviet ones, most does not includes the place of origin in store listings. Commercial websites like Ebay, Amazon, and AliExpress won't give you relevant search results most of the time as well. Things may not be able to be done the easy way, but two approaches have yielded the best results:

Chinese search strings:[]

In order to actually find Chinese listings, it's necessary to translate English search terms into Chinese characters and search using those, instead of typing them directly. This works best on websites like AliExpress where a good portion of the listings are made by Chinese companies.

- Upsides: Fairly easy to find modern production, Chinese-made filters if all you want is something.

- Downsides: Search results will be vague and very restricted. A lot of products, like the type 3 filters described above, are extremely hard to find using this method. Listings are made by middleman companies, so who knows what you're actually ordering.

Chinese domestic websites (Taobao):[]

Taobao is the Chinese domestic version of AliExpress. Best results can be obtained when the language settingis changed to English.

- Upsides: Search results are very specific and finding things is very easy. Prices are incredibly low, even with shipping factored in.

- Downsides: Making and verifying an account is extremely difficult and the website is inaccessible without one. Oftentimes a forwarding service, like Superbuy, is necessary to get them overseas. Good luck with customs.