Ok I’ve got a professional precision and efficient DUST PARTICLE COUNTER. And it’s come in a box ,in a box. And the reason I’ve got it, I’ve read a few articles on line about micro particle production, or emission from filament from 3D printing and I wanted to be able to check while printing what kind of quantity of particles are produced and to then make a decision whether to enclose the printers and filter the air when working with them. I mean this seems ok, and I’ve already put the battery in and I’ve used it a few times. It seems to be working. Although I haven’t been able to identify a test to see if this is accurate. Essentially what I’ve done is watch a Matthias Wandel video where he used a particle counter and looked at reading he was getting, and compared them to what I was getting with this thing here in the workshop. And it seems more or less accurate. I manged to change the settings so that I have three different size of particle that I’m reading. 0.3, 2.5, and 10 Micrometers. And it’s reading at PPL – pieces per litre and as far as I can tell that’s very similar to parts per million. And what I’m going to do is run a few tests with this, while using my sander with and without the extraction, with two different type of sandpaper, and also an air filter on and off, and we’ll see what kind of readings we get from this thing here.
The firs thing to mention is you also get reading of the temperature and relative humidity, so in this room (May 2018) it’s 20 degrees C at the moment, coz it’s warming up now it’s summer. And the humidity is about 51% but I do have a de-humidifier running pretty much non stop in here.
So lets start by doing a sample count. Essentially what you do is press RUN, you get a count down from 50 seconds and about half way, you get an initial reading. And at the end you get the sample reading. Ok that’s a lot higher then last time. Normally it’s around 10000. In the book there’s a reference table somewhere. That’s heavy solution. Interesting.
I’m going to turn my air filter on, and do a couple readings and write those down. Normally when I do any cutting or sanding I have this on in the background.
I’m going to go do a reading outside. Ok I’ve just come back from outside. And that’s outside. That’s really high. I actually took this to work with me and used it while changing the bags in the dust extraction room. I didn’t see any at 10 micrometers come up on the reading but it went up to 90,000 for 0.3. and I thought that was a lot.
It seems on this fine day in London, the pollution is quite high. But I’m going to just check the pollution and pollen count from the met office and compare it to what I’m getting in my area. Maybe it’s just a particularly bad day.
Ok I’ve found a website. London air pollution real time air quality index, HX1. So I’m in Wandsworth at the moment. So their reading is 112 PPM at 2.5 micrometers, and I’m getting 380 PPL.
So 1 part per million is equivalent to 1 million grams of something per L of water. The readings on this are equivalent to PPM. It’s quite high. I’m going to do some readings in other parts of the building.
Ok so I’ve just run around the building doing a few different counts and it’s consistently high everywhere. The website I found with a live pollen count or pollution count, seems to high as well so they seem to correlate. (correlation doesn’t equal causality) I guess it depends on the area. Peaks and troughs. I think what I’ll try today. There’s no point doing the sanding experiment coz it will effect the readings but I’m going to turn my fan on. Take the hose off the extractor for the table saw under there. That’s got a HEPA filter. I’m going to let that run for a little bit. I’ll also do the same for the numatic over there. Give it a couple minutes running and then turn this on and run it again.
Ok it has dropped down a bit. Maybe if I left the two extractors and the air scrubber running for quite a while longer maybe that would drop down even more but I think I’m battling against real life now and I ain’t going to win in this leaky building. It’s dropped from 140 to 110. So there’s no point doing the sanding experiment today.
Another way to check how much dust your producing – albeit in a qualitative way, is the Tyndall beam dust lamp. Look at this shot from my previous video. The camera is acting like an observer, while my body is blocking the light source which is behind me. And the shadow behind the saw help illuminate the dust coming off the machine. So if you don’t have a dust counter or not willing to spend the money to get one, you can still check whats coming off your machines, and think about changing how your extraction operates or other preventative measures to reduce your exposure. Compare the previous shot with this one from a different angle, and you barely see any dust coming off the machine – but it’s still there. I’ll link to the particle counter that I’m using and some other examples, and well as a video from the HSE on how to check for dust using the Tyndall dust lamp. Hope that was interesting. Thanks again for watching and you’ll catch me in the next one.