Dylos Air Particule Conter experiment maintenance.

Posted on October 21st 2013
Share: aqicn.org/faq/2013-10-21/dylos-air-particule-conter-experiment-maintenance



Note: this article was written in 2013. While the Dylos monitor is still a good product, there is nowdays much better and affordable monitoring products, so we do not recommend purchasing the Dylos product anymore.
You can for instance check the GAIA air quality monitoring stations product range from ES Labs.


The Dylos Air Particle Counter experiment is still going-on, and has been on for now 50 days. So, last weekend, as the air pollution in Beijing was getting really low - thanks to strong north winds, we used this time as an opportunity to perform a maintenance break... on the Dylos monitor itself.

The reason is that, even if the Dylos monitor is definitely well designed and engineered equipment (we do mean it), it maybe not be so well conceived to subsist Beijing's tough episodic Air Pollution.

It all started after noticing that the correlation graphs between the Dylos and BAM monitor tend to show some systematic signs of leveling beyond 38,000 particles (≥0.5µ). This kind of saturation symptom can be the consequence of internal air inflow bottleneck, which can be caused by "saturated" air channels. During times of heavy pollution, this phenomenon is totally normal due to the large amount of particulate matter having to go through the air channel.

So, no surprise, after opening the Dylos monitor, we confirmed that the internal air channels are definitely saturated, by an accumulation of dust during the last 50 days:

 
-Beijing dust impact on the Dylos air particle counter internal structure-


The result of cleaning the internal structure, using a fine brush, would produce an astonishing amount of dust - and this, just after 50 days of outdoor experimentation. Just think that this is what you are breathing...


-The real Beijing dust... the one Beijiners breathe during heavy pollution day!-


Actually, having to perform such cleaning and maintenance on the Dylos equipment is not a surprise, since even the very expensive BAM equipment requires monthly maintenance by skilled operators.


--

The following part has been added 10 days after the initial post was published:

It is now 10 days since the cleaning has been done, and the situation has definitely improved for the correlation between BAM and Dylos. From the graph below, which shows the measurements before and after the cleaning, the zone indicated with number (2) shows a very good similarity (correlation) between BAM and Dylos. But, under condition of heavy pollution, there are still consistent signs of leveling (deviation in measurement), as highlighted with zone number (1) and (3). The deviation seems however less worse after the cleaning (zone (3)) than before (zone (1)). We are contacting the Dylos company, to consult them on this leveling phenomenon, and will update this post later.


(Click on the picture to open the real time version)

--


Click here to see all the FAQ entries
  • Nitrogen Dioxyde (NO2) in our atmosphere
  • Ozone AQI Scale update
  • Kriging Interpolation




  • comments powered by Disqus

    À propos de la qualité et de la mesure de la pollution atmosphérique:

    A propos des niveaux de qualité de l'air

    IQANiveau de pollution de l'air Impact sur la santé
    0 - 50BonLa qualité de l'air est jugée satisfaisante, et la pollution de l'air pose peu ou pas de risque.
    51 -100ModéréAir quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.
    101-150Mauvais pour les groupes sensiblesLa qualité de l'air est acceptable; Cependant, pour certains polluants, il peut y avoir un problème de santé modérée pour un très petit nombre de personnes qui sont particulièrement sensibles à la pollution de l'air.
    151-200MauvaisTout le monde peut commencer à ressentir des effets sur la santé; les membres des groupes sensibles peuvent ressentir des effets de santé plus graves.
    201-300Très mauvaisAvertissements de santé de conditions d'urgence. Toute la population est plus susceptible d'être affecté.
    300+DangereuxAlerte de santé: tout le monde peut ressentir des effets de santé plus graves.

    Pour en savoir plus sur la qualité de l'air, consultez le sujet Qualité de l'air sur wikipedia ou le guide AirNow de la qualité de l'air et de votre santé .

    Pour des conseils de santé très utiles de Docteur Richard Saint Cyr, consultez le blog myhealthbeijing.com.


    Usage Notice: All the Air Quality data are unvalidated at the time of publication, and due to quality assurance these data may be amended, without notice, at any time. The World Air Quality Index project has exercised all reasonable skill and care in compiling the contents of this information and under no circumstances will the World Air Quality Index project team or its agents be liable in contract, tort or otherwise for any loss, injury or damage arising directly or indirectly from the supply of this data.



    Paramètres


    Paramètres de langue:


    Temperature unit:
    Celcius