PurpleAir Classic Air Quality Monitor
PurpleAir Classic Air Quality Monitor
PurpleAir Classic Air Quality Monitor
PurpleAir Classic Air Quality Monitor
PurpleAir Classic Air Quality Monitor
PurpleAir Classic Air Quality Monitor
PurpleAir Classic Air Quality Monitor

PurpleAir Classic Air Quality Monitor

Regular price
Sale price

The PurpleAir Classic air quality monitor is the original and popular PurpleAir sensor. It measures real-time PM2.5 concentrations for residential, commercial, or industrial use and can be installed indoors or outdoors. Built-in WiFi enables the air quality measurement device to transmit data to the real-time PurpleAir Map, which is stored and made available to any smart device. 

The PA-II is available in two editions. The SD edition includes an onboard SD logger to record and store data without a WiFi connection.

Please note: This sensor does not come with a power adaptor. Find a suitable OUTDOOR-rated adaptor here or use your own USB power source (any 5V, 1.2 to 2.4 amp adaptor will work).

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  • Classic PurpleAir PA-II particulate sensor
  • Dual Laser Particle Counters (PMS-5003)
  • Pressure, Temperature & Humidity Sensor (BME280)
  • WiFi connectivity with data stored in the cloud
Classic PurpleAir dual laser particulate sensor
Dimensions 3.5 in x 3.5 in x 5 in
(85 mm x 85 mm x 125 mm)
Color White
Power requirements 5V USB Micro, 0.18A continuous, 600mA peak
Intended Use Outdoor and indoor use
WiFi Yes
Expansion Port No
Internal Storage No
Warranty One (1) year limited warranty
Laser Particle Counters

Class 1 Laser. A Class 1 laser is safe under all conditions of normal use.

Manufacturer Plantower

This device contains two particle detectors to provide redundancy and help determine sensor health.

Type PMS-5003 (2)
Range of measurement 0.3, 0.5, 1.0, 2.5, 5.0, & 10 μm
Counting efficiency 50% at 0.3μm & 98% at ≥0.5μm
Effective range
(PM2.5 standard)*
0 to 500 μg/m³
Maximum range (PM2.5 standard)* ≥1000 μg/m³
Maximum consistency error (PM2.5 standard) ±10% at 100 to 500μg/m³ & ±10μg/m³ at 0 to 100μg/m³
Standard Volume 0.1 liter
Single response time ≤1 second
Total response time ≤10 seconds
Pressure, Temperature, & Humidity Sensor
Manufacturer BOSCH
Model Number BME280
Temperature range -40°F to 185°F (-40°C to 85°C)
Pressure range 300 to 1100 hPa
Humidity Response time (τ63%): 1s
Accuracy tolerance: ±3% RH
Hysteresis: ≤2% RH

Contains Transmitter Module FCC ID: 2AC7Z-ESPWROOM02D

Wireless Networks 802.11b/g/n @ 2.4GHz
(WPA2 pre-shared key or open networks)
Certificates FCC/CE/TELEC/SRRC
Tx Power 802.11 b: +20 dBm
802.11 g: +17 dBm
802.11 n: +14 dBm
Rx Sensitivity 802.11 b: -91 dbm (11 Mbps)
802.11 g: -75 dbm (54 Mbps)
802.11 n: -72 dbm (MCS7)
Antenna Type 2 dBi on-board PCB antenna

FCC Compliance Statement (Part 15.19)

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:

  1. This device may not cause harmful interference, and
  2. This device must accept any interference received, including interference that may cause undesired operation.

Warning (Part 15.21)

Changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to operate the equipment.

FCC Interference Statement (Part 15.105 (b))

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one of the following measures:

  • Reorient or relocate the receiving antenna.
  • Increase the separation between the equipment and receiver.
  • Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
  • Consult the dealer or an experienced radio/TV technician for help.

To comply with FCC/IC RF exposure limits for general population / uncontrolled exposure, the antenna(s) used for this transmitter must be installed to provide a separation distance of at least 20 cm from all persons and must not be co-located or operating in conjunction with any other antenna or transmitter.

Customer Reviews

Based on 7 reviews
Steve Frost
power and price

These are great units that work well, the price and power issues keep them from being great. Need a solar option and reduce the price to get more of these out in all areas of the country.

Thank you for your review. You can find more information about using solar power: https://community.purpleair.com/t/off-the-grid/119. Here is a post where community members discuss how they’re using solar: https://community.purpleair.com/t/solar-power-pole-mount/1049

Just right

It does exactly the job we wanted. Getting it online was a little more involved than anticipated, but in the end we got it working.

Ron Fleshman
Waste of money

My data is not available. Sensor download tool has been retired. I will need to hire someone to write scripts to collect my data. I need data history available for research.

Ron, we have a new data download tool that is also open source here: https://community.purpleair.com/t/purpleair-data-download-tool/3787. We will also be happy to help if you contact us: https://www2.purpleair.com/pages/contact-us

Jeff Silva
Amazing service

We started working on an order several months ago but had some hold-ups on our end. When we reached back out to Purple Air they seamlessly picked up right where we left off. Great service team.

Erich Britton
User Friendly, Good Customer Service

Received the monitors within a few days of placing the order. Set up was really easy. Prompt response to my questions from customer service regarding some technical questions on manipulating the website/map to meet our needs.