Apollo AIR-1 Air Quality Sensor

Quick verdict

A purpose-built air quality sensor that feeds PM2.5, VOC, NOx, temperature, and humidity directly into Home Assistant via ESPHome, with CO2 available through the optional SCD40 add-on. No cloud, no subscription, no account. Use it to alert you when PM2.5 spikes during wildfire season, or to trigger ventilation on CO2 once the add-on is fitted. Straightforward setup and solid value for the sensor coverage you get.

Standout: All-in-one air quality sensor covering PM2.5, VOC, NOx, temperature, and humidity (with optional NDIR CO2), fully local via ESPHome.

Notes last checked May 31, 2026.

Compatibility snapshot

Why it stands out

• comprehensive air quality monitoring including PM2.5, VOC, NOx, temperature, and humidity in one device, with CO2 (NDIR SCD40) as an optional add-on
• ESPHome firmware means fully local operation with easy customization
• enables powerful automations like triggering ventilation when PM2.5 spikes, or on CO2 with the optional SCD40 fitted

Reasons to hesitate

• WiFi-based, which adds to wireless network load
• no display on the device itself, so you need Home Assistant or a dashboard to read values
• no native voice assistant integration without Home Assistant

Best for

• Home Assistant users who want comprehensive indoor air quality data for health-conscious automations
• anyone who wants to monitor PM2.5, VOC and NOx locally without sending data to a cloud service (CO2 needs the optional SCD40 add-on)

Avoid if

• you just need temperature and humidity. Simpler and cheaper sensors exist for that
• you want a standalone air quality monitor with a built-in display

Privacy and local-control notes

Fully local via ESPHome. No cloud, no account. Air quality readings stay entirely on your local network.

Home Assistant support: supported · integration path: ESPHome.

Built with ESPHome - see the ESPHome guide for Home Assistant →

Buying reality check

Price notes: Mid-range pricing is fair for the number of sensors included. Comparable commercial air quality monitors cost more and require cloud accounts.

Compare side by side: see sensor comparisons →

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