I'm still wearing my mask.

People are talking about "post-pandemic" and "after Covid" as if it's now. Considering what I read about long-Covid and current case numbers, I am not quite ready to leave my mask and safety-protocols completely.

Ian Ozswald asked in his newsletter:

I feel comfy wearing these [masks] as I can see them puff in/out as I breathe, so there's a pressure difference to the external environment so most of the air I breathe is filtered. Have you found anything better for public traveling?

this caused me to info-dump my research. As it has become a fairly thorough piece of information on how I think about personal protection in the pandemic, I decided to share it here. Mind you, this is non-expert advice.

I've put a bit of thought and research into the Covid-protection question. Most of it already when I was living in the UK I felt abandoned, so I looked for countries that had a better response at the time. I looked towards Germany and South Korea and what they recommend / enforce.


There are many types of masks. From "single-ply cloth" to professional respirators. It's important to have the full information on types to go for:

Different Types

First, I found that the cloth masks are absolutely outdated and anyone should wear a surgical mask at the least. Although that is very much the minimum. Second, the FFP(2) masks are of a higher standard, so let's do a quick dive into FFP masks.

The one with a one-way valve are obviously a bad vibe and tell everyone that you only care about yourself, so I recommend staying away from them. So let's look at filtration values according to the EN 149 standard:

  • FFP1: Max 25% leakage / 22% average
  • FFP2: Max 11% leakage / 8% average
  • FFP3: Max 5% leakage / 2% average

That generally translates to this:

FFP1 is for non-toxic and non-fibrogen particles, definitely out for this pandy. FFP2 is an overall min. 95% protection and applicable for health hazards. So it's good to go for us. Technically FFP3 is rated at 99% protection and technically against viruses and microorganisms. The FFP2 is basically equivalent to North American N95 masks.

But obviously this is a scale and cost question. Requiring FFP3 would simply be infeasible and FFP2 and N95 especially, when mutually worn is a pretty good lowest common denominator.

Quality of Masks

Quality control issues. There are fakes out there, here are the places that can actually CE certify masks: CE Certification sites

Within those standards, I found some FFP2 with better and worse fits even within the same manufacturer. Bit annoying, but what can you do. Hope for the best when they come in, and try them on before taking them with you is what I do.

Safety and Fit

Here's a guide how you're supposed to put on various PPI from the German RKI translated to English: Robert-Koch-Institute - How to put on the Mask

Here's a German video testing the fit of a mask:

Basically, what I took from is: Push the mask tight and breathe out to test for leakages. Adjust the nose bridge for a tight fit.

Here are some other things about safety and fit:

  • A beard will reduce the efficacy of a mask. (I read about 80-90%.) Here are some facts and mitigation techniques. [PDF]
  • Wearing the mask under your chin will tire out the elastic bands and reduce fit, also there's possible cross-contamination.
  • Don't touch the inside of the mask
  • Avoid contact of the mask with possible cross-contaminants like cash in pockets etc.
  • Mark your own mask so as to not wear masks from others

I have now had two types of elastics on the mask. Earloops and "around the head"-loops. In my personal experience the earloops are quite variable and don't always have great fit. I could feel some draft on some models. Headloops have been the tightest fit of mask, I have experienced and felt the safest.

There are pros and cons to both loop-styles: I feel like the earloops can't put as much pull, as they'll become uncomfortable in no time. On the pro side, they're easy to take off for a drink, snack and passport control checks. The around-the-head loops have the best protection I would say. But they're impossible to take off with one hand, especially if you wear noise-cancelling headphones like me.

Mask Reuse

Technically these masks are single use, but since you're not working in a health environment, it's ok to let masks dry out and reuse them.

This means, we need to cycle through masks, as it takes 7 days for Covid levels on the mask to deminuish to tolerable levels, when worn in shops and private use. [Source]

There are two ways to dry masks. Air-drying in your room, or baking the mask at 80°C top-and-bottom heat in an oven for an hour. [Source [PDF]] Remember to let it cool, before the next use.

There are many ways not to dry the masks. Do not put them on heaters, as that creates the ideal environment for funghi and bacteria to grow. Don't throw them in the washer, diswasher, or microwave either.

Finally, dispose the mask after 5 uses or when the breathing resistance is getting higher.

When to Wear

Anywhere inside that isn't private or safe. Outside where there are many people.

So people will look funny at you in the UK, but here in Bonn until recently, the city centre had a mask mandate. On the streets everywhere. Something to consider. In Edinburgh I made a risk assessment of streets, when they were relatively full, I'd avoid and/or wear my mask.

My daily driver are FFP2 masks. For plane travel I consider FFP3 masks. If I have to go back to taking the bus / train somewhere and can't avoid large crowds, I will consider FFP3 masks.

Technically, you are not supposed to wear these masks longer than 75 minutes, followed by a 30 minute break. Moreover, not during higher exertion. However, with the current return to the office that is rarely possible.

General Safety

Rules I go by:

  • Avoid crowded closed rooms (if a shop is "full" go somewhere else)
  • Open windows for ventilation if possible (also on buses)
  • When you were outside and touched anything, your hands are contaminated, wash them.
  • Choose travel times that are off-peak to avoid large crowds
  • Take the bike anywhere possible, it's safe cheap and healthy (yes even in rainy UK, but I get it it sucks)
  • Social distancing is still a good rule of thumb, so slalom around people even if it's inconvenient
  • It's ok to leave a room if someone is openly coughing / sneezing
  • No hand shakes, at best fist-bumps or elbow bumps
  • If I get Covid, I'd prefer by doing something cool, rather than work. If work is unsafe, I remove myself from the situation.
  • Remote & outside as much as possible
  • Think about the network effect of unmasked contact. (The whole thing about bubbles they tried back in the day, but really who are the people you are meeting with meeting? In a bus that is a huge network, in a 2-people office it would already be 2 families at the least, so possibly a 2nd degree network of two entire Kindergardens... Risk assessment as always)

I'm incredibly privileged that I haven't caught Covid and could work remotely. I don't have a family and not a lot of friends I meet, so while it is very lonely, I can be fairly safe covid-wise. Unfortunately I have to, because I have some health-stuff that would possibly have me die if I caught it. But regardless, I'm aware my isolation isn't something everyone can afford. But I think the things and info I described was fairly "this is how everyone can reduce their risk" rather than "I have had direct contact to less than 10 people in 2021 and physical contact once to one person", which is not really reproducible for anyone. Here in Bonn I have been much more social, but still as careful as possible, according to all of the above.

One example is that I am still religiously wearing my mask. I even wear it in the gym during workouts, when the total amount of masks I have seen during my workout today was 2, of which 1 was an employee. It has a signaling effect for most people too that they leave me fairly alone, which I appreciate. But it is a personal choice that goes against the grain, which I make to keep myself safe while still going out. I've definitely stood at the door of places and turned around because they were too full with too many unmasked people.

That's all I have collected from experts I trust. So today in May 2022, I stick to these. We'll see how that will change and evolve in the future, for the worse or better.