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Every verdict links its standard or listing Sourced

The CO-shutoff exists. CPSC says most generators sold still don't have it.

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Portable-generator carbon monoxide is associated with roughly 80 deaths a year, and CPSC's own modeling says machines built to UL 2201 would avert nearly all of them — while "compliance appears to be minimal." For every generator line we record whether a CO shutoff exists and who stands behind the claim: a third-party UL listing, a manufacturer-stated PGMA G300 citation, or marketing with no standard at all. We test nothing and give no safety advice — we index the record.

Claim vs standard
No CO-shutoff system at all
CPSC: ~80 deaths/yr; compliance "minimal"
No shutoff
the CPSC record
Named thresholds, named standard (G300-2023)
The claim shape worth rewarding
G300 stated
by the maker

What each verdict means

A verdict describes who stands behind a CO-shutoff claim — not whether a generator is safe. No shutoff makes indoor or garage use safe; CPSC's placement guidance is the operative document, and a sensor is a backstop for mistakes, not permission.

UL 2201 certified

Third-party certification with a public listing — shutoff plus reduced CO emissions. CPSC modeling: ~100% of deaths averted.

G300 (mfr-stated)

The maker names ANSI/PGMA G300 and its edition. Real and specific — but self-declared; PGMA runs no listing. (~87% in CPSC's modeling.)

Advertised, no standard

A branded shutoff system with no named standard located. Better than nothing; checkable against nothing.

No CO shutoff

No system at all — per CPSC, still most units sold, and the machines behind the death toll.

Every generator line: claim vs the standard behind it

Showing of lines · sorted by strength of the backing · last reviewed 2026-07

Verdict
Generator line CO system The claim Verdict Source
Ryobi RY907022FI — RY907022FI (7,000W inverter)CO shutdown, certified by UL to ANSI/UL 2201“The first portable generator UL-certified to ANSI/UL 2201 (March 2018)”ul2201-listedUL — "UL Certifies First Low Carbon Monoxide Portable Generator to ANSI/UL 2201"
Honda EU2200i (CO-Minder) — EU2200i (and the CO-Minder lineup)CO-Minder — continuous CO monitoring with auto-shutdown (600 ppm instant, or 400 ppm 10-minute average)“CO-Minder across the lineup; Honda states its models meet ANSI/PGMA G300-2023”g300-statedHonda — CO-MINDER system page (thresholds)
Champion CO Shield models — CO Shield models (100571 3500W inverter et al.)CO Shield — CO auto-shutoff“"CO Shield meets the requirements of ANSI/PGMA G300-2018"”g300-statedChampion CO Shield model listing (G300-2018 statement)
Generac CO-Sense models — CO-Sense models (GP series)CO-Sense — CO detection with auto-shutdown“CO-Sense advertised on select models”shutoff-advertisedGenerac product materials (CO-Sense; standard citation not located)
Westinghouse CO Sensor models — "CO Sensor" suffix models (iGen/WGen)CO sensor with auto-shutdown on designated models“"CO Sensor" shutdown advertised on designated SKUs”shutoff-advertisedWestinghouse product materials (CO Sensor variants; standard citation not located)
DuroMax CO Alert models — "CO Alert" modelsCO Alert — CO detection with auto-shutdown“CO Alert advertised on newer models”shutoff-advertisedDuroMax product materials (CO Alert; standard citation not located)
Predator CO Secure models — "CO Secure" modelsCO Secure — CO shutdown on designated models“CO Secure shutdown advertised on designated models”shutoff-advertisedHarbor Freight product materials (CO Secure; standard citation not located)
Wen CO Watchdog models — "CO Shutdown Watchdog" modelsCO Shutdown Watchdog on designated models“CO Shutdown Watchdog advertised on designated models”shutoff-advertisedWen product materials (CO Watchdog; standard citation not located)
Generators without any CO shutoff — Models sold with no CO-shutoff system at allnone“(no CO system — and per CPSC, still most of what's out there)”no-shutoffCPSC — voluntary standards report (compliance minimal; deaths data; effectiveness modeling)

A verdict describes who stands behind a CO-shutoff claim — a UL listing, a manufacturer's named-standard citation, or nothing — not whether any generator is safe. We test nothing and give no safety advice; no shutoff makes enclosed-space use safe (CPSC: outdoors only, 20+ feet from the home, exhaust pointed away — why the sensor changes less than you'd think). CO systems ship on designated SKUs, not whole brands — check the model. Some product links are affiliate links — if you buy through them we may earn a commission, at no cost to you. Links appear only on rows with a named standard behind them, and they never change a verdict.

Why this table is different

Certified ≠ stated ≠ advertised

UL 2201 comes with a third-party listing you can look up. A G300 citation is the maker's own statement. A branded "CO-something" with neither is just a feature name. Three claim strengths, three tiers. The standards, compared →

The denominator is deadly

~80 deaths a year, 43% of all consumer-product CO deaths — and CPSC's finding that most units sold comply with neither standard. The gap between available technology and the shelf is the story. The record →

A shutoff is not permission

Every tier on this site can still kill in a garage. The sensor is a backstop for placement mistakes — CPSC's outdoor-placement guidance stays the operative document at every price point. What it changes →

CO shutoff, model by model

The question that should be on every listing, answered from the record.