Calibration

Today I bought an Ironbox; Philips make, 1100 watts.

There's a knob to adjust temperature for specific type of cloth materials....wool, linen, cotton, silk, etc., At home, I started pressing my dresses with different temperature levels.

A doubt arised that how could I know the temperature of that level which the knob indicates. That is, if I position the knob in "Cotton", the ironbox will function at the temperature for the cotton material. But, is that temperature what actually set for that level? How do I know? Even if I suppose to believe the manufacturer during the initial days of my purchase, would it (the temp level) not be changed on later days?

How could I check that the ironbox is working at the required temperature level what I require? And, how much it deviates from the actual temperature level?

Any procedures available to check it?

Is this the commercial testing and calibration? If yes, which part of the ironbox to be tested and which part to be calibrated.....with which standard?

http://www.ni.com/pdf/testsummit/us/Calibration.pdf
http://www.qualitymag.com/articles/88760-management--calibration-can-be-risky-business
http://www.capterra.com/calibration-management-software/
https://www.gemeasurement.com/sites/gemc.dev/files/4sight_datasheet_english_0.pdf
http://www.bis.org.in/lab/labs.htm
http://www.bis.org.in/org/AnnualReport0708.pdf
http://www.encyclopedia.com/topic/National_Bureau_of_Standards.aspx