What I want to do
- To detect airborne asbestos
- To create a small, cheap instrument that is easy to use
- To be able to detect the asbestos in the presence of other airborne particles
Current research
At this point I have not attempted any experiments, however within publiclab Amysoyka has looked at the detection of settled asbestos fibers using sticky tape. The next stage to this would be to look at airborne asbestos as this would mean that members of the public could determine quickly if they have asbestos particles in the air they are breathing.
Why is this important?
Asbestos comes into several classes blue, brown and white, all are needle like particles with varying flexibility. One of the reasons that asbestos is bad for the body is that it can puncture parts of the lung. With many properties pre-2000 containing asbestos the remaining asbestos in the building can cause health issues for builders, engineers and ardent DIYers. The current mode of detection utilises X-rays and microscopy, these are time intensive processes, and can be quite expensive. Due to the long processing time it means that people can still be walking around in an area in which it is not safe to be.
ALERT sensor
The centre for atmospheric and instrumentation research (CAIR) at the University of Hertfordshire have developed a method which uses two lasers and a magnetic field in order to detect asbestos. The initial reports of this method were unclear about why the magnetic field was needed, especially as it is an expensive addition. The reason behind using the magnetic field is that asbestos particles are para-magnetic this means the structure aligns in a magnetic field. The premise of their method is that you monitor the airborne dust pre-field and either post-field or while the particles are in the field. The former measuring if there are fibrous particles present and the latter measuring how many are aligned.
What I am thinking
Having seen the ALERT sensor I am not 100% how their sensor works step-by-step however, as shown in the diagram I think it can be simplified. The first laser detecting unaligned particles and the second detecting the aligned particles. I haven't quite worked out the best way to get an air flow, or the best positioning of the second laser.
Questions and next steps
Having looked at what is out there the question is; can we replicate it at a lower cost than the $800 that they estimate? The next step will be to do a cost analysis of IR lasers and detectors as they are likely to be the bulk cost. A consistent low power method of generating an electric field also needs to be explored.
If you have any thoughts, please input. The more people there are the better we can make it.
7 Comments
Further questions that need exploring:
Following some literature * What does the data look like * What is a positive result? * What is a negative result? * How does detection work? * What wavelength do they use? * Can we get a hold of a broad range IR light for IR spec characterisation or do we just use a single wavelength and stick with diffraction?
I am reading through this journal now/ by monday and will post findings as and when.
Is this a question? Click here to post it to the Questions page.
Reply to this comment...
Log in to comment
@el_tonio
Your image has me thinking it might be worth using a piece of metal piping & turning it into an electromagnet.
Also, found this article online: https://www.emlab.com/s/sampling/env-report-12-2008.html
It explains quit well three different methods used for testing for asbestos fibers.
Reply to this comment...
Log in to comment