IRR describes rejection within an infrared measurement point or range, while TSER describes the percentage of total solar energy rejected across the solar spectrum. IRR is useful only with its wavelength and method clearly stated; TSER is normally the broader comparison for total solar performance.
A high IRR figure may cover only one test point
IRR may be reported at a selected wavelength such as 950 nm or 1400 nm. Two products can display similar headline percentages while behaving differently across the wider solar spectrum.
TSER considers the whole solar-energy balance
TSER accounts for transmitted, reflected and absorbed solar energy across the relevant spectrum. It should still be read together with the glass system, VLT and installation conditions.
Real comfort is a complete-system result
Film construction, reflection, absorption, vehicle or room volume, glazing area, air-conditioning, orientation and weather all influence what occupants feel.
Frequently asked questions
Can two films with 99% IRR feel different?
Yes. They may be measured at different wavelengths or manage absorption and reflection differently.
Does the highest TSER always mean the best choice?
Not always. The selected film must also meet visibility, appearance, glass compatibility and practical use requirements.