@catcheun Thanks for your post, I’ll point you toward this thread which links to and discusses the VOC graphs, etc. on Dyson smart purifiers at length:

May I know what does it mean (the circled part) . It’s calibrated for 6 hours . Does it mean VOC is detected but not showing in the reading yet ? 

Hi @catcheun,

It’s showing that the current level of VOCs detected by your Dyson purifier is within the Good (green) range - ie, the lowest levels on the scale. From your other screenshot, it’s showing as 0, as is NO2. PM10 and PM2.5 are both showing as 1, respectively - also within their Good range.

You can click the further tabs (Air Quality, PM2.5, PM10, VOC, NO2, Temperature and Humidity) within the graph for a more detailed breakdown throughout the day. You can see my own example below, where the VOC levels began to spike when I started cooking dinner, before returning to their normal low levels over the next few hours!

Thank you and is VOC stay in 1 for days  ( except it goes back to 0  when window is open). Something is off gassing? 
 

my older model doesn’t read VOC unless the source is pretty close to it . Is there anything I can do about it ?

many thanks 

Hi @catcheun,

Our VOC sensors detect a wide range of gases including some you can't smell - such as gases from cleaning products. Although the room may smell clean, there may still be something present. It's not possible for us to pinpoint exactly what the source would be in this particular instance.

Your machine will purify most efficiently when the window is closed, but of course there are times you may want to open the window for ventilation.

Thanks Jack, 

  It’s just not coming back to 0

Hi Jack as for the photo

i have posted circling VOC tight next to the 48% humidity. 
What does that stands for ? VOC is the dominant pollutant? 
 

Hi @catcheun,

I noted what you’ve highlighted and I did mention in my reply above - it’s showing that the current level of VOCs detected by your Dyson purifier is within the Good (green) range - ie, the lowest levels on the scale. If the VOC levels detected were high, it would be showing orange or red next to the VOC label. 

Hope this clarifies things!

Thanks Jack, 

I just feel a bit uneasy having a little kid at home. i am hoping to find out my VOC source.

I had the Dyson Pure cool for many years and it doesn't registered we have VOC unless I used Clorox or husband farted next to it. With the relatively newer Purifier cool, it’s a bit more sensitive may be?

This month I noticed the VOC number doesn't go back to 0 this month. WIth both side by side. The older unit remain 0 but it does registered Clorox. The newer unit always stays at 1 in the living room and 2 on the bedroom level. The newer unit  it goes up to 3 or 4 when we do normal activities such as doing the laundry and mouthwash, which i understand. 

It is normal for a household to have VOC at level 2 at all times?

 I am just trying to figure out the source. 

Hi @catcheun,

Thanks for your further question but as I’ve mentioned, unfortunately it wouldn’t be possible for me to guess at what precise source could be causing the VOC reading you’re currently seeing in your particular home environment. It is possible your new machine is slightly more sensitive than your older one - but to reiterate, the range of readings you’ve described (0-4) is in the Good - Fair range, which shouldn’t be a concern.

Sorry I’m not able to provide a conclusive answer here!