What is carbon monoxide?
This page explains carbon monoxide (CO), the one gas where the Embry-Riddle test measured a clear drop. It matters because CO is a real safety hazard, and because CO numbers are easy to misread.
Plain definition
What carbon monoxide is
Carbon monoxide (CO) is a gas with no color and no smell. It forms when fuel burns without enough oxygen to finish the job. Complete burning turns carbon into carbon dioxide (CO₂); incomplete burning leaves some as CO.
Gasoline engines, generators, furnaces, heaters, grills and wood stoves can all make it.
Plain definition
Why it is dangerous
CO sticks to the part of your blood that carries oxygen, so less oxygen reaches the body. Early symptoms — headache, dizziness, weakness, nausea — are often mistaken for the flu.
Poisonings are more common in winter, especially from portable generators used during power outages. Never run a generator or engine indoors or in a closed garage, and keep a CO detector in the home.
Plain definition
How CO is measured
Concentrations are often given in parts per million (ppm) or as a percent of the gas sample. A gas analyzer on an exhaust pipe reports concentration — how much CO is in each sample — not the total amount the engine made.
So a percent change in a CO reading is a change in concentration under those test conditions. It is not, by itself, a change in total pollution.
Measured
What the test measured
The Embry-Riddle test — an Embry-Riddle Aeronautical University master’s (M.S.) thesis (2026) — found about 34% less carbon monoxide (CO) in an idle test. Carbon dioxide (CO₂), oxygen and hydrocarbons did not change significantly.
The −34% is carbon monoxide only. It is not a drop in all emissions.
Seller claim
Seller-reported CO numbers
The seller’s Thunderstorm.tech page reports CO 97.1% lower in a Dartford, UK test (June 28, 2024), 98.00% lower in a Clearwater, Florida test (June 24, 2024), and unchanged at 0.10% at Star Cement in the United Arab Emirates (UAE) (December 5–6, 2024).
These are reported by the seller. This site has not seen the full reports, and the conditions differ from test to test.
Outside commentary
Why engineers watch CO
Wikipedia’s engine water-injection article notes that water injection may reduce carbon monoxide or nitrogen oxides, which is one ordinary explanation outside writers offer for CO changes in devices that add water vapor.
Sources
Pages we opened and read for this explainer. The label in parentheses says which side each one speaks for.
- Wikipedia — Carbon monoxide poisoning (reference; sources, symptoms, prevention) (opens in a new tab)
- Wikipedia — Water injection (engine) (reference) (opens in a new tab)
- Hall, W. (2026), Embry-Riddle Aeronautical University master’s thesis (measured) (opens in a new tab)
- Thunderstorm.tech — Test Results (seller’s site) (opens in a new tab)
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