All calculations are based on the official index table:
https://github.com/Limych/ha-iaquk/blob/845760b87067cdd8b6831542c46d80975ad8a9c3/IAQ_Rating_Index.pdf
25°С = 1 point (Inadequate)
37% = 4 points (Good)
650 ppm = 4 points (Good)
then the sum (9 points) is approximated for the entire range (1-65), since not all sensors are represented.
Hmmm, I see, that is, since my comfort temperature does not match the IAQ UK, I need to exclude the temperature from the sensor, and then it will work well for me, because now it shows the same thing and it is always bad.
Do I understand this correctly? Or can I make adjustments in it to understand that it’s fine, but tailored to my individual needs?
The sensor only calculates an estimate of the air quality according to a predetermined system. How you use this estimate is up to you.
The “Seeed Studio Grove - Multichannel Gas Sensor V2” seems to be a nice sensor for the job. Hopefully this sensor will be added to the EPShome library soon.
This is great, sadly I’m in the USA where AQI is different than IAQ. Any chance there’s a component like this that can spit out AQI from a PM2.5 sensor? Thanks.
I used the following formula as a template sensor to convert pm2.5 to US AQI:
You’re awesome thank you so much.
Dude, @fahr that is awesome! I didn’t even think about an AQI value, until your post. Just yesterday I got my first pm2.5 sensor from AliExpress (pms7003) and got it working on ESPHome because they recently integrated the pmsx003. I took your equation and matched it up with the one on Wikipedia’s AQI page and adapted it for use in an ESPHome template sensor and template text sensor for the color:
uart:
rx_pin: 16
baud_rate: 9600
globals:
- id: c_low
type: float
- id: c_high
type: float
- id: i_low
type: float
- id: i_high
type: float
sensor:
- platform: pmsx003
type: PMSX003
pm_2_5:
name: "Particulate Matter <2.5µm Concentration"
id: pm25
accuracy_decimals: 1
filters:
- sliding_window_moving_average:
window_size: 60
send_every: 31
send_first_at: 11
# https://en.wikipedia.org/wiki/Air_quality_index
- platform: template
name: Air Quality Index
unit_of_measurement: AQI
icon: mdi:pine-tree-fire
accuracy_decimals: 0
lambda: >
if (id(pm25).state > 500.4) {
return NAN;
} else if (id(pm25).state >= 350.5) {
id(i_high) = 500.0;
id(i_low) = 401.0;
id(c_high) = 500.0;
id(c_low) = 350.5;
} else if (id(pm25).state >= 250.5) {
id(i_high) = 400.0;
id(i_low) = 301.0;
id(c_high) = 350.4;
id(c_low) = 250.5;
id(aqi_color).publish_state("Maroon");
} else if (id(pm25).state >= 150.5) {
id(i_high) = 300.0;
id(i_low) = 201.0;
id(c_high) = 250.4;
id(c_low) = 150.5;
id(aqi_color).publish_state("Purple");
} else if (id(pm25).state >= 55.5) {
id(i_high) = 200.0;
id(i_low) = 151.0;
id(c_high) = 150.4;
id(c_low) = 55.5;
id(aqi_color).publish_state("Red");
} else if (id(pm25).state >= 35.5) {
id(i_high) = 150.0;
id(i_low) = 101.0;
id(c_high) = 55.4;
id(c_low) = 35.5;
id(aqi_color).publish_state("Orange");
} else if (id(pm25).state >= 12.1) {
id(i_high) = 100.0;
id(i_low) = 51.0;
id(c_high) = 35.4;
id(c_low) = 12.1;
id(aqi_color).publish_state("Yellow");
} else {
id(i_high) = 50.0;
id(i_low) = 0.0;
id(c_high) = 12.0;
id(c_low) = 0.0;
id(aqi_color).publish_state("Green");
}
return round(((id(i_high) - id(i_low))/(id(c_high) - id(c_low))) * (id(pm25).state - id(c_low)) + id(i_low));
text_sensor:
- platform: template
name: AQI Color
icon: mdi:pine-tree-fire
id: aqi_color
update_interval: never
One thing to note, my ESPHome implementation doesn’t perform a 24 hour average for the AQI index calculation – I may implement that down the road.
It works GREAT:
The cool thing is, the wiring for this device is even simpler than the BME280 that @Limych shared above. It’s literally three pins (+5V, GND, and RX). Ignore the incorrect BLE CLIENT RADON label. 
I’m going to build a few of these and put them in and around the house. 
One more thing to add here. I bought a Blueair 280i air purifier and it measures VOC and CO2 content. I have had the thing for a week or two and I have been pitting its PM values against the homebrew values but I had no way to crosscheck the VOC nor CO2 values, until now!
I found the CCS811 and it’s supported by ESPHome! This is probably the same sensor used by the 280i that I have because on power-up the device calibrates itself and the CO2 value is stuck at 400, this happens on the 280i as well. The CCS811 is i2c and 3.3V.
According to the ESPHome sheet on the CCS811, if you have temperature and humidity to feed into the device it will give you a more accurate reading so I dropped in a DHT22 and fed the readings to it. The DHT22 is also 3.3V.
Now my breadboard looks like this:
That gives me all of this output:
And here’s the config file for it:
uart:
rx_pin: 16
baud_rate: 9600
i2c:
sda: GPIO21
scl: GPIO22
globals:
- id: c_low
type: float
- id: c_high
type: float
- id: i_low
type: float
- id: i_high
type: float
sensor:
- platform: dht
pin: GPIO19
temperature:
name: "Living Room Temperature"
id: living_room_temperature
humidity:
name: "Living Room Humidity"
id: living_room_humidity
update_interval: 60s
- platform: ccs811
eco2:
name: "Living Room CO2"
filters:
- filter_out: 65021
tvoc:
name: "Living Room TVOC"
filters:
- filter_out: 65021
address: 0x5A
update_interval: 60s
temperature: living_room_temperature
humidity: living_room_humidity
# baseline: 0xF4FF
- platform: pmsx003
type: PMSX003
pm_1_0:
name: "Living Room Particulate Matter <1.0µm Concentration"
id: living_room_pm_1_0
accuracy_decimals: 1
filters:
- sliding_window_moving_average:
window_size: ${my_window_size}
send_every: ${my_send_every}
send_first_at: ${my_send_first_at}
pm_2_5:
name: "Living Room Particulate Matter <2.5µm Concentration"
id: living_room_pm_2_5
accuracy_decimals: 1
filters:
- sliding_window_moving_average:
window_size: ${my_window_size}
send_every: ${my_send_every}
send_first_at: ${my_send_first_at}
pm_10_0:
name: "Living Room Particulate Matter <10.0µm Concentration"
id: living_room_pm_10_0
accuracy_decimals: 1
filters:
- sliding_window_moving_average:
window_size: ${my_window_size}
send_every: ${my_send_every}
send_first_at: ${my_send_first_at}
- platform: template
name: Living Room PM 1.0 rolling 30 minute average
id: living_room_pm_1_0_rolling_30_minute_average
unit_of_measurement: µg/m³
icon: mdi:molecule
update_interval: 2s
lambda: >
return id(living_room_pm_1_0).state;
filters:
- sliding_window_moving_average:
window_size: 900
send_every: 15
send_first_at: 15
- platform: template
name: Living Room PM 2.5 rolling 30 minute average
id: living_room_pm_2_5_rolling_30_minute_average
unit_of_measurement: µg/m³
icon: mdi:molecule
update_interval: 2s
lambda: >
return id(living_room_pm_2_5).state;
filters:
- sliding_window_moving_average:
window_size: 900
send_every: 15
send_first_at: 15
- platform: template
name: Living Room PM 10.0 rolling 30 minute average
id: living_room_pm_10_0_rolling_30_minute_average
unit_of_measurement: µg/m³
icon: mdi:molecule
update_interval: 2s
lambda: >
return id(living_room_pm_10_0).state;
filters:
- sliding_window_moving_average:
window_size: 900
send_every: 15
send_first_at: 15
# https://en.wikipedia.org/wiki/Air_quality_index
- platform: template
name: Living Room Air Quality Index
unit_of_measurement: AQI
icon: mdi:pine-tree-fire
accuracy_decimals: 0
lambda: >
if (id(living_room_pm_2_5_rolling_30_minute_average).state > 500.4) {
return NAN;
} else if (id(living_room_pm_2_5_rolling_30_minute_average).state >= 350.5) {
id(i_high) = 500.0;
id(i_low) = 401.0;
id(c_high) = 500.0;
id(c_low) = 350.5;
} else if (id(living_room_pm_2_5_rolling_30_minute_average).state >= 250.5) {
id(i_high) = 400.0;
id(i_low) = 301.0;
id(c_high) = 350.4;
id(c_low) = 250.5;
id(living_room_aqi_color).publish_state("Maroon");
} else if (id(living_room_pm_2_5_rolling_30_minute_average).state >= 150.5) {
id(i_high) = 300.0;
id(i_low) = 201.0;
id(c_high) = 250.4;
id(c_low) = 150.5;
id(living_room_aqi_color).publish_state("Purple");
} else if (id(living_room_pm_2_5_rolling_30_minute_average).state >= 55.5) {
id(i_high) = 200.0;
id(i_low) = 151.0;
id(c_high) = 150.4;
id(c_low) = 55.5;
id(living_room_aqi_color).publish_state("Red");
} else if (id(living_room_pm_2_5_rolling_30_minute_average).state >= 35.5) {
id(i_high) = 150.0;
id(i_low) = 101.0;
id(c_high) = 55.4;
id(c_low) = 35.5;
id(living_room_aqi_color).publish_state("Orange");
} else if (id(living_room_pm_2_5_rolling_30_minute_average).state >= 12.1) {
id(i_high) = 100.0;
id(i_low) = 51.0;
id(c_high) = 35.4;
id(c_low) = 12.1;
id(living_room_aqi_color).publish_state("Yellow");
} else {
id(i_high) = 50.0;
id(i_low) = 0.0;
id(c_high) = 12.0;
id(c_low) = 0.0;
id(living_room_aqi_color).publish_state("Green");
}
return round(((id(i_high) - id(i_low))/(id(c_high) - id(c_low))) * (id(living_room_pm_2_5_rolling_30_minute_average).state - id(c_low)) + id(i_low));
text_sensor:
- platform: template
name: Living Room AQI Color
icon: mdi:pine-tree-fire
id: living_room_aqi_color
update_interval: never
I put the filter_out values on the VOC and CO2 because the sensor throws out a MAX value when it first fires up. If you’re charting the results, you can’t see the real stuff when it starts coming in. Anyway, here’s to fresh air!!
For the benefit of anyone else, after the fact, when using most CCS811 sensor modules:
Remember to connect the WAKE pin to GROUND.
Otherwise, your CCS811 sensor won’t even show up on the I2C bus scan.
Thanks @FredTheFrog, I didn’t run into this issue. I should probably ground mine for good measure…
I reviewed four or five different references for different CCS811 sensor modules and code, and it wasn’t until I found one that finally provided that reminder, that my sensor started working as expected. Just thought I’d save someone else a LOT of frustration. 
@Limych im using a BME680, can you help in letting me know which sensor values to map to create the IAQ value?
bme680_gas_resistance
bme680_humidity
bme680_pressure
bme680_temperature
thanks
for IAQ (or do you mean AQI?) have a look here BME680 gas resistance values - #15 by jorgenn or have a loook at the new BME680 bsec integration
Many thanks to Limych for creating this. I’ll be buying you a coffee.
Just testing this with my PM (HM330X), CO2 & TVOC (SGP30) and temp+humidity (AM2301) sensors.
All on an ESP32 running Tasmota FYI.
Couple of questions, as I’m not a Lovelace master by any means;
Thanks again.
Nice component. Would it be possible to take into account ozone and sulfur dioxide?
With this setup are you still using the interval so you only turn on measurement for 20s every 2 minutes or do you measure air quality continuous?
My live versions are very close to what I shared previously. I have like six of them all over my house. They measure continuously but I primarily use the rolling data because of the inaccuracy of the instantaneous data. Noise doesn’t help anyone make a decision.
If you look at “official AQI number” reporting, you’ll see that the average is rolled by 24 hours which causes significant delay in reporting… it takes a long time to move the needle when a nasty air front moves in quickly. With a 30 minute rolled average the results are nearly real time by comparison.
I have great visibility to see the quality of the air from my house and now I can align what I see with what is actually happening. Mostly I wanted i know: is it just fog in the valley or is it bad air and we should stay inside? The AQI sensor tells me.
I also use the room-based data to trigger air purifiers that I have in the house should the room’s air quality start to degrade. I throttle the purifier based on how “bad” the AQI measurement is. It works very well.
Woah, I just noticed that ESPHome’s integration for PMS5003ST and PMS5003S now have support for formaldehyde! Lately, I’ve been trying to register my 3D printer’s impact to room air quality with the PMS7003 sensors I bought but nothing seems to register – even TVOC/CO2. I know that printing ABS generates formaldehyde (which is pretty much all I print) so I’m going to get a couple of these PMS5003ST sensors and see what it can see. 
I just installed and got this working. I love this component, but I am not a programmer. The Indoor air quality UK component makes use of a function that has been depreciated and will soon no longer function. It looks like there is a replacement available. Is there any chance you will be updating this component before it stops working?
This is the Home assistant log message:
Logger: homeassistant.helpers.frame Source: helpers/frame.py:77 First occurred: 7:50:15 AM (1 occurrences) Last logged: 7:50:15 AM
Detected integration that uses temperature utility. This is deprecated since 2022.10 and will stop working in Home Assistant 2023.4, it should be updated to use unit_conversion.TemperatureConverter instead. Please report issue to the custom integration author for iaquk using this method at custom_components/iaquk/__init__.py, line 355: value = convert_temperature(value, entity_unit, TEMP_CELSIUS)
I would really appreciate your help keeping this component alive.
Nice work, but my sensors are coming up as sensor.unnamed_device.
I don’t believe I missed a step in the config, did i?
iaquk:
livingroom:
name: "iaq Living Room"
sources:
temperature: sensor.woonkamer_temperature
humidity: sensor.woonkamer_humidity
co2: sensor.livingsensor_co2_value