Wildly high PM25 values from api

i’ve noticed this for the past several weeks and finally put some logging in to catch it. I’m got dozens of these from just today. pm25 value is over 2000 and sometimes much higher. no way this is correct right? i’ve put some code in on my side to just catch these and set the value i show to at least a more plausible number (300). any ideas?

sensor=206005 sensor_index=206005 pm2.5=4055.1 dist=18.0km uri=https://api.purpleair.com/v1/sensors/206005?fields=pm2.5

Possibly dust or spiderweb in the sensor. Blow it out with whatever compressed air you have available.

i’m a dev using the api, so it’s not my physical sensor. and it’s quite a few with this issue. these are from just the last hour

sensor=126231 sensor_index=126231 pm2.5=3075.5
sensor=133141 sensor_index=133141 pm2.5=3329
sensor=123453 sensor_index=123453 pm2.5=3297.6
sensor=183603 sensor_index=183603 pm2.5=3328.8
sensor=114745 sensor_index=114745 pm2.5=3227.3
sensor=48541 sensor_index=48541 pm2.5=3327

looks similar to this issue and is just part of having unmaintained sensors out in the world. does make me question the validity of the whole platform though tbh as these sensors age and start pumping out bad data. i’m seeing up to about 100 of these a day in my data

Scott, we have seen this issue occasionally happen with Plantower laser counters before, and we believe it’s an issue with the firmware implementation of CF1 and ATM in the laser counter (firmware we don’t have access to). Try getting the Alt-CF3.4 data instead.

We’ve got a new map coming soon, and it will display Alt-CF3.4 data by default, with the option to switch back to ATM/CF1 (corresponding with outdoor/indoor sensors).