New HVAC Technology

New HVAC Technology

Direct Ventilation Monitoring (DVM): measured, not modelled.

Poppy monitors daily cycles of outdoor atmospheric tracer concentrations and matches them to indoor levels. The difference between how they cycle outdoors vs. indoors reveals the OA intake rate for the building — so you know exactly how much outdoor air reaches each area.

Signal

Atmospheric tracer cycle match

outdoor ↔ indoor

Resolution

Zone-level

breathing zone

Cadence

Continuous

24 / 7 / 365

Standard

ASHRAE 62.1

62.1 · 241 aligned

Integration

None

no BMS, no Wi-Fi

How it works

Four steps. No BMS required.

No step uses BMS data, damper feedback, or CO₂ proxy. DVM relies only on physical atmospheric tracer concentrations measured in place.

MONITOR

Step 01

Outdoor reference

Local outdoor atmospheric tracer concentrations are sampled continuously to establish the diurnal reference cycle for each site.

continuous
SENSE

Step 02

Indoor measurement

Portable Poppy sensors placed in the breathing zone of each area record the same atmospheric tracer species at matched cadence. No BMS hookup.

continuous
COMPARE

Step 03

Cycle differencing

The delta between outdoor and indoor cycles (amplitude, phase, and damping) is proportional to how much outdoor air the zone is actually pulling in.

per zone
SOLVE

Step 04

OA intake rate

Poppy resolves the zone-level outdoor-air intake rate — CFM and CFM/SF — and compares it to the ASHRAE 62.1 zone target.

updated hourly

Measurement

The indoor cycle is the outdoor-air rate.

If indoor concentrations track outdoor swings tightly, the zone is over-ventilated. If they stay flat, it's under-ventilated. Use the selector to compare profiles against the code-target band.

Atmospheric tracer concentration over 48 hours

How DVM sees your building breathe

Poppy monitors daily cycles of outdoor atmospheric tracer concentration and compares them to indoor levels. The phase delay — how far behind outdoor the indoor cycle lags — reveals the OA intake rate, zone by zone.

Patent Pending
HighMidLow0h12h24h36h48hAtmospheric tracer concentrationOutdoorIndoorΔ Low delay

Phase delay

Low delay→ Energy wasted

Indoor follows outdoor almost instantly — the zone is flushed so fast that the two cycles nearly overlap. Lots of outdoor air, but far more than code requires.

System specs

System parameters.

Sensing

MediumMulti-species atmospheric tracer concentration (outdoor + indoor)
PlacementBreathing-zone portable sensors, Poppy-maintained
CoverageZone-level — one station per monitored area
ConnectivityCellular uplink · no BMS, no Wi-Fi required

Reference

Outdoor sourceLocal ambient monitoring at site
CadenceContinuous — diurnal cycles resolved
SynchronizationOutdoor and indoor sampled at matched timestamps

Analysis

ModelCycle-matching of outdoor vs. indoor atmospheric tracer concentration
OutputOA intake rate per zone (CFM, CFM/SF)
ComparisonZone target per ASHRAE 62.1 Table 6-1
SavingsWeather-normalized per IPMVP Option B

Deployment

TimelineScreening call → 2–4 week assessment → 72-hr report
Tenant impactNone — sensors are passive and in-room
IntegrationNo BMS, damper feedback, or VAV command data used
OngoingContinuous monitoring + drift alerts post-tuning

Why DVM

DVM vs. common alternatives.

Every common approach infers outdoor-air delivery from commands or occupancy proxies. DVM measures the physical outcome.

DimensionDVMBMS inferenceCO₂ proxy
Primary signalAtmospheric tracer-cycle match (direct)Damper position (inferred)CO₂ rise (proxy)
Measures actual OA?Yes — directlyNo — commanded, not deliveredNo — estimated from occupancy
Zone resolutionPer breathing zonePer VAVPer sensor
BMS requiredNoYesSometimes
ContinuousYes — 24/7/365Yes (but inferred)Yes (but indirect)
ESG / IPMVP-defensibleYes — weather-normalizedNoNo

Standards alignment

HVAC standards framework.

[1]

ASHRAE 62.1-2022Ventilation for Acceptable Indoor Air Quality

Zone outdoor-airflow requirements (target)

[2]

ASHRAE 241-2023Control of Infectious Aerosols

Clean-air delivery rate methodology

[3]

IPMVPInt'l Performance Measurement & Verification Protocol

Option B — retrofit isolation, verified savings

DCV gap

70% of air consumption runs below the DCV threshold.

Demand-Controlled Ventilation cuts outside air when CO₂ climbs above its threshold. The problem: in most commercial buildings, roughly 70% of total air consumption occurs below that threshold — so DCV never engages on the majority of the operating envelope. DVM measures what you actually deliver, whether CO₂ is high or not.

DCV · REACTIVE

Engages above CO₂ setpoint

Dormant during the 70% of operating hours where CO₂ sits below the threshold.

DVM · CONTINUOUS

Measures across full envelope

Quantified breathing-zone ventilation — every zone, every hour.

FIG.02b · COVERAGE OVER 24H OPERATING WINDOWthreshold = 1000 ppm CO₂
DCV thresholdDCV active · 30%DVM measurement · 100% coverage00:0006:0012:0018:0024:00
Scope of measurement

The only thing that matters is what happens in the breathing zone.

Not what the rooftop schedule says. Not what the DCV algorithm assumes. Not what the commissioning report logged three years ago. The occupied breathing zone is the whole point of ventilation, and it's the only place performance can be verified.

Measurement plane
What it represents
DVM target
rooftop / AHU
commanded airflow at the supply fan
duct / VAV
inferred volume at the terminal box
commissioning report
point-in-time, often 3+ years old
breathing zone
air actually delivered to the occupant
✓ YES

Get started

Request a method brief or start a DVM assessment.

30-minute screening call. If your building qualifies, we deploy DVM sensors at no cost and deliver a 72-hour zone-level report before any setpoint change.

We use cookies to improve your experience and analyze site traffic. By continuing, you agree to our Privacy Policy.