# What does TIR stand for in Window Pane Fenestration?

When looking at glazings within various public databases I see the fields "tir" shown often. E.g as seen below:

"glazing_data": {
...
"tir_front": 0.0,
"tir_back": null,
...
}


What does this field stand for?

• – Jebathon Nov 20 '20 at 16:52
• That was my first thought but I dismissed it as it never applies to glazing because we never use it in that mode (looking through the edge of the glass). The air-glass-air refraction can't generate total internal refraction - unless the gasses are different on each side of the window. Post a link. – Transistor Nov 20 '20 at 20:06
• Could you point us to the database you got this example from? – Wasabi Nov 21 '20 at 0:07
• Have you considered: thermal infrared? – Fred Nov 21 '20 at 3:46

## 1 Answer

TIR: Thermal infrared (longwave) transmittance of the glazing layer.

Lawrence Berkeley National Laboratory has a windows program called THERM 6.3 / WINDOW 6.3 NFRC Simulation.

In pp 55 of this manual, there is a table referencing some properties of the glazing, including this.

here is the Therm 6.3 prog dowmload.

• Thank you. The data was from IGDB too – Jebathon Nov 23 '20 at 21:31