Why Some Air Purifiers Talk to Your Building — and Most Don't

Most commercial air purifiers are appliances. You plug one in, it runs, and unless someone walks over and looks at it, you have no idea whether it's actually keeping up — or whether the filter needs changing, or whether the room it's in even has a problem. Multiply that across a 40-unit office building or a multi-site portfolio, and "air quality management" becomes a walking tour.

Fellowes' Array line does something different: it's built to talk to your building automation system over BACnet, the open protocol that's run HVAC, lighting, and life-safety integration for 30 years.

What BACnet actually is. BACnet (ANSI/ASHRAE 135, also ISO 16484-5) became an ANSI standard in 1995 specifically so that HVAC and building equipment from different manufacturers could talk to each other on the same network without a proprietary bridge for every vendor. It's maintained by ASHRAE's own standards committee, currently at ANSI/ASHRAE 135-2024, and there are over a thousand manufacturers with registered BACnet vendor IDs. If your building has a BMS — a Niagara, Honeywell, Siemens, or JCI front end — it almost certainly already speaks BACnet. That's the whole point: it's the common language, not a proprietary add-on.

What that means for air purification specifically. Every unit in the Array line — the AR1/AR2 recessed ceiling units, the AC2 ceiling-suspended, the AW1/AW2 wall-mounted, the AS1/AS2 floor stands — carries a full sensor suite (PM1, PM2.5, PM10, TVOC, CO2, relative humidity, and temperature) and reports it live. The Array Relay gateway connects the whole system to your BMS over BACnet/IP through a single Ethernet cable, and Array Viewpoint gives you a cloud dashboard across one room, one building, or an entire portfolio — instead of a light on a box that tells you nothing once you've left the room.

Why it's more than a nice-to-have. Two concrete reasons this matters operationally, not just as a feature checkbox:

1. ASHRAE 62.1 demand-controlled ventilation. If your building uses CO2-based DCV, 62.1-2022 requires sensor accuracy within ±75 ppm at 600 and 1000 ppm, factory calibration, recalibration at least every 5 years, and a fail-safe to minimum design outdoor air if a sensor goes down. A networked sensor that reports continuously into your BMS gives you a documented, ongoing compliance record — not a one-time balancing report that's already stale by the time an inspector asks for it.
2. LEED, WELL, and Fitwel points. All three certification frameworks reward continuous, documented IAQ monitoring over point-in-time testing. A BACnet-integrated system that's already logging PM2.5, CO2, and TVOC across the building gives your sustainability team something they can actually cite, rather than a spreadsheet from the last time someone brought in a handheld meter.

Why this is worth asking your HVAC contractor about, not your office-supply rep. Getting real value out of a networked air purifier means it has to actually get onto your BMS — pointed at the right BACnet device instances, mapped into your existing graphics, alarmed correctly. That's a controls integration job, not a "plug it in and it just works" purchase. It's also exactly the kind of work ETS already does every day on the HVAC side — which is a different conversation than the one you'd have buying the same box from an office supply catalog that ships it and is done.

If you're speccing IAQ for a renovation, a LEED/WELL push, or just want visibility into air quality across a building instead of trusting an appliance in the corner, that's worth a conversation before you buy the box.