Coronavirus 2019-2020 thread (no unsubstantiated rumours!)
- Thread starter localizer
- Start date
That’s is pretty risky. For one, it might not even work. I know Australia tried and failed when potential vaccine it was researching on caused a false positive hiv result!
for another, even if it works it might come with serious side effects like the AZ one
I can only speak for what was going on in China. But it sounds like there were serious issues with the procurement process in the UK.
For one, none of the masks made here had a "best before" date. The government mandates that certain information must be included on the packaging, including date of production, place of origin, validity period (usually 2 years or 18 months from production date), model name and number, etc. Wherever your masks were sourced from, they clearly had some serious QC issues.
I contacted the NHS and procurement channels in the UK multiple times in June 2020. Same response every time: "We have enough supply of masks, don't need more thanks." Clearly there was a severe shortage on the ground, yet these institutions weren't willing to buy more. Or maybe it was due to political reasons that they didn't want to buy from a Chinese exporter, and preferred to continue struggling with a shortage instead?
I agree that the first few batches of masks were abysmal. In my factory we struggled to get the manufacturing right for the first few weeks but after experience with supplying the domestic market, the quality gradually became better for export. By April 2020 there weren't any more major defects (e.g. ear loops coming off, metal strip falling out).
broadsword
Brigadier
From the photos I've seen in China they generally are made in clean rooms:
This was Feb 2020
There are different grades of masks and different grades of clean rooms. If we were making computer chips, we would need a clean room "devoid of human contact" but it's not necessary to go that far for masks.
Surgical masks (and other medical-grade devices) are made in a basic low-level clean room which filters out most large particles. The ear-loops then have to be attached manually by workers using ultrasonic welding machines. Anyone entering the production area has to wear disposable overalls.
This only applies to medical/surgical masks as they need to be tested for microbial cleanliness (i.e. cleanliness from germs and microbes). Non-medical KN95s were not fully designed for use in a medical environment and therefore don't have this test requirement, so they don't need to be made in a clean room.
In practise, medical and non-medical KN95s are very similar. The filtration requirements are the same. The main difference is that medical-grade respirators have fluid protection to protect wearers against bodily fluids and spray during invasive surgery. So for the vast majority of medical staff in a pandemic situation, non-medical KN95s are actually quite sufficient.
broadsword
Brigadier
Is the fabric imported? I read that it was sourced from Switzerland. If it is, why is there no local company making it?
The majority of meltblown polypropylene (i.e. the filtration fabric) is not imported. Given the choice, every mask manufacturer would prefer to buy it domestically as they have the best prices. I have heard a few cases of imported meltblown from countries like Brazil or Korea in other factories, but the majority is still sourced locally.
As I mentioned before, mask production became quite ridiculous and the fabric supply could not keep up. Only a few companies had experience making high-grade meltblown PP (usually conglomerates like Sinopec, or China Petroleum) and their production was completely full. To make it worse, there were also many hoarders and scalpers. Pre-pandemic it cost 20k yuan for 1 ton of meltblown, but during mid-2020 it peaked at 700k for 1 ton. That's the biggest reason why KN95 prices (at wholesale) ballooned from 50 cents in February 2020 to almost 2 dollars in May 2020.
After several weeks of fruitless searching for legit high-grade meltblown, our factory set up our own production in-house to supplement the scarce supply from outside suppliers. It was difficult and the quality was terrible at first, but eventually we got it to an acceptable level (~70% PFE) and began to use it in masks. By double or triple-layering the fabric, we can achieve 95% in the final product which passes as a KN95.
This medium-grade meltblown is also good to use in surgical masks as the filtration requirements are lower, only 90-95% BFE needed vs 95% PFE for KN95s. BFE stands for Bacteria Filtration Efficiency which means the filtering of particles of 3.0 microns. PFE, Particle Filtration Efficiency, measures the filtering of ALL particles, tested using 0.3 micron particles which are the most difficult to capture.
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CGTN street interviews Taiwanese regarding their vaccine dilemma. Although I expected that CGTN will be very biased in their reporting, this video is rather neutral, with little political innuendos that we are used to seeing elsewhere. Actually, I am wondering how did CGTN reporters get their press credentials from Taipei considering the bellicosity of the DPP.