Commercial metering and elevated pressure. Episode sixty-eight of the Gas Service Animated series.

The residential diaphragm meter has two big siblings, and commercial services run at pressures that would flatten a house regulator. One episode on the hardware that feeds big buildings — and where your wrench legally stops.

The rotary meter: two lobed impellers spinning in a machined case, measuring by trapped volume — accurate across a huge range, compact, and fussy about one thing: clean gas. Debris scores the lobes, so rotaries live behind strainers, and many sets include bypass piping so the meter can be serviced without dropping the building.

The turbine meter: a rotor spun by the gas stream, counting velocity — the choice for large, steady loads like big boilers and process gas. It wants developed flow and steady demand; wild swings and slugs of debris are its enemies. Rotary for rangeability, turbine for volume: that's the pairing.

Commercial services deliver at pounds — two, five, ten, sometimes more — so the meter set carries regulators with relief, and every rooftop unit or mechanical room downstream gets its own pounds-to-inches regulator with a vent run to code. The two-psi episode's logic, multiplied: stage the pressure down close to the load, and every regulator's vent is sacred.

Big sets get physical protection: bollards where vehicles maneuver, seismic bracing where the map says so, clearances kept clear of storage and snow. A forklift and a meter set is a headline; the concrete post is the whole safety plan.

Multiple meters demand identification — the code requires each meter and its piping be marked for the space it serves. On a strip plaza, 'no gas in unit four' starts with reading tags, because the fastest outage fix in commercial work is discovering someone closed the wrong valve.

Your work at a commercial set: verify the symptom — inlet versus outlet pressures, dynamic under load with everything firing; read the tags; check the customer-side regulators and their vents; and document. The meters, the set regulators, the bypass: utility equipment, utility hands. The boundary from the no-gas season, with more zeros.

And carry the load-growth reflex: every rooftop added, every kitchen expanded, every generator installed draws against a set sized years ago. Chronic low pressure at high fire across a building is a capacity conversation with the utility — the tankless trap at building scale.

Commercial metering in one breath. Rotary for range behind a strainer; turbine for steady volume. Pounds delivered, staged down at each load, every vent honored. Bollards, tags, and dynamic measurements. Prove the symptom, respect the boundary, and watch the load grow. That's the commercial season.