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1Scan for outdated or missing drivers - takes under a minute2Repair Windows errors before they cause bigger problems3Fix the driver behind crashes, sound loss and screen glitchesIS-Instruments says its Notus gas Raman system detected methane, carbon dioxide, ethylene and carbon monoxide at low-ppm concentrations in recent tests, using the same instrument without adjustments between gas measurements. The results, published on 15 September 2026, are manufacturer-reported: the report says Notus was undergoing independent testing ahead of full market launch, but it does not include an independent test report or a complete test protocol.
What the Notus tests report
The report covers four gases at the concentrations shown below. Its signal-to-noise ratios and timings are reported test results; the detection limits are estimates, not direct demonstrations at those lower concentrations.
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| Gas | Test concentration | Reported signal-to-noise ratio | Reported measurement or integration time | Detection-limit statement |
|---|---|---|---|---|
| Methane | 10 ppm | Above 60 | Under one minute, using a short fibre length | Estimated in the hundreds of ppb with the current configuration; tens of ppb are described as possible with longer fibre lengths and extended integration, not demonstrated in the reported tests. |
| Carbon dioxide (CO₂) | 10 ppm | Approximately 14 | One-minute integration | No detection limit stated in the report. |
| Ethylene | 10 ppm | 25 to above 50 across multiple observed peaks | One minute | Potential limit estimated in the hundreds of ppb with the current setup. |
| Carbon monoxide (CO) | 5 ppm | Approximately 10 | The report summary says measurements were completed in one minute or less, but gives no gas-specific timing here. | Estimated around 1 ppm. |
These figures are from IS-Instruments’ 15 September 2026 report and are not independently confirmed specifications. “Low-ppm” describes the concentrations actually tested—10 ppm for methane, CO₂ and ethylene, and 5 ppm for CO—not the estimated lower detection limits.
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A detection limit is not the same thing as a concentration directly tested and detected. The report gives direct results at the ppm concentrations in the table, then estimates lower limits from those results. In particular, the hundreds-of-ppb figures for methane and ethylene are estimated or potential limits; the report does not say that the system directly measured either gas at those concentrations. The roughly 1 ppm CO limit is also an estimate.
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IS-Instruments says establishing the true limit at very low concentrations requires a sufficiently well-characterized reference sample. It identifies access to calibrated samples with adequate certainty as a constraint on assessing Notus’s ultimate performance. The estimated limits should therefore not be treated as validated product specifications.
What the multi-gas result establishes—and what it does not
The report says the same Notus instrument measured all four gases without adjustments between measurements. That supports a claim of multi-gas flexibility in the reported setup. It does not show how Notus compares with another analyzer: the report provides no comparative test establishing superior sensitivity, speed or cost.
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The CO₂ result also has a stated identification challenge. IS-Instruments says the Raman peaks used to identify CO₂ lie close to nitrogen peaks. It reports scattering cross-sections of 1.5 and 1.7 for the two CO₂ peaks, compared with 8 for methane, but does not specify units for these figures in the report text. They should not be used as a standalone comparison of instrument performance.
How the gas Raman system works
IS-Instruments describes Notus as a gas Raman system. In its technical explainer, the company says hollow-core optical fibre enhances interaction between the laser and the gas sample. The available description does not provide enough detail to characterize the full optical design or quantify how much the fibre contributes to the reported results. Read the company’s technical explainer on trace-gas detection with Raman spectroscopy for its account of the approach.
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Testing and product status
The report, authored by Sarah Marsh-Collings, says Notus was undergoing independent testing ahead of full market launch. It does not publish an independent validation, price, retail listing, release date or purchasing specification. Its publication date is 15 September 2026, so it does not establish the product’s current availability after that date.
The reported results and test caveats are described in the IS-Instruments Notus test report.
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