Which generators have no CO shutoff at all?

Last reviewed July 2026.

No — and that is still most of the market. CPSC's own finding, verbatim shape: compliance with UL 2201 "appears to be minimal", and compliance with PGMA G300, "although greater, is still lacking for most models or units currently being sold." Portable generators are associated with roughly 80 CO deaths per year in the US — 43% of all consumer-product CO deaths in CPSC's jurisdiction — and CPSC modeling says UL 2201-class machines would avert nearly all of them. That gap between what the technology can do and what most units on the shelf actually have is the reason CPSC opened mandatory rulemaking in 2023 — and the reason this site exists.

The facts on file

Sources — read them yourself

• CPSC — voluntary standards report (compliance minimal; deaths data; effectiveness modeling)
• Federal Register — Safety Standard for Portable Generators (NPRM, Apr 2023)

How to read this

Two ANSI standards govern generator CO safety, and they are not equal claims: UL 2201 is third-party certified with a public listing (and per CPSC's modeling, machines built to it would avert nearly 100% of generator CO deaths); ANSI/PGMA G300 conformance is stated by the manufacturer (~87% in the same modeling). An advertised shutoff with no named standard is better than nothing and checkable against nothing. See the two standards compared — and remember a shutoff is not permission.

See every generator we track, verdict by verdict → · the cost-per-running-watt ranking →

Generator Score indexes CO-shutoff systems against the two ANSI standards and the public record (UL listings, manufacturer citations, CPSC data), with attribution — we test nothing and give no safety advice. No CO-shutoff system makes a generator safe to run indoors, in a garage, or near openings — CPSC's placement guidance (outdoors only, 20+ feet from the home, exhaust pointed away) is the operative document, and a shutoff is a backstop for mistakes, not permission to make them. If a maker publishes a standard citation or a listing appears, the page changes — the record wins.