One headline percentage is not a complete specification.
Three metrics, three questions
| Metric | What it describes | What to check |
|---|---|---|
| VLT | Visible light passing through the tested sample. | Film-only or filmed-glass measurement. |
| IRR | Infrared rejection under a stated method. | Wavelength or range, calculation and sample setup. |
| TSER | Total solar energy rejected by filmed glass. | Glass substrate and comparable test conditions. |
Why IR numbers need context
Infrared rejection may be reported at a selected wavelength or across a range. Different infrared metrics can also account for absorbed energy differently. Do not treat IRR, IRER and selective infrared measurements as interchangeable labels, or assume every manufacturer uses the same definition.
A high IR figure is not the percentage of all solar energy rejected. For an overall solar comparison, review TSER alongside the other specifications and the measurement notes.
Compare like for like
Build your comparison sheet with separate columns for model, VLT, TSER, infrared metric, test range and substrate. Mark an unspecified test detail as a question for the supplier, rather than filling the gap with an assumption.
For an OEM enquiry, send the target application and the values you want to evaluate. Ask for matching samples and the corresponding data sheet so your team can compare a named product with a named specification.
Keep the decision traceable
Record the sample code and the data-sheet version with your evaluation notes. A well-labelled comparison is more useful for a repeat order than an isolated percentage copied from an advertisement.
Quick questions
Does 99% IRR mean 99% total heat rejection?
No. An infrared metric and TSER describe different scopes; request the method and wavelength information.
Can two IRR figures be compared directly?
Only after confirming compatible measurement methods, wavelength ranges and sample setups.
Technical references
Definitions and measurement context: IWFA Automotive Education Guide and 3M Automotive Window Film comparison guide — key terms. These references explain general concepts; they do not verify VEYMAN product performance.
Compare a film for your market
Tell VEYMAN your application, target specifications and sample requirements.