Testing, Certification, and Labeling
This domain tests whether you can read a certification label, explain what backs it, and know its limits. Questions present a label string, a test report or a project specification and ask what the document proves and what it does not.
How certification works
- An accredited independent laboratory tests the product to NAFS, including air leakage (ASTM E283), water penetration and structural performance (ASTM E330), in a defined sequence.
- The certifier issues a listing and requires ongoing factory quality control audits so the label remains valid.
- Thermal ratings follow NFRC: simulation (NFRC 100 for U-factor, NFRC 200 for SHGC and VT) or testing (NFRC 102), certification, and listing in the NFRC Certified Products Directory with a published label.
- Safety glazing is labelled separately under 16 CFR 1201 or ANSI Z97.1, and impact-rated assemblies reference ASTM E1886/E1996 on the label.
Reading a label
A typical NAFS certification label carries the standard and year, the performance class and grade (for example AW-PG50), the size tested (for example 72 in by 96 in), the operator type and the certification programme. The rated size is the largest qualified size; smaller units in the certified line are covered, larger ones are not.
Worked example
A submittal shows a label reading R-PG30, size tested 48 in by 60 in, but the project has 60 in by 72 in units on a third-floor wall with a calculated 35 psf. Reasoning: three problems exist at once. The performance class R is questionable for that building, the grade PG30 is below the required 35 psf, and the unit exceeds the tested size so the certification does not extend to it. The correct response is to require a product tested and certified at the project size with a grade of at least 35 psf in an appropriate class, not to accept the label.
Traps that cost marks
- Confusing the NFRC thermal label with proof of structural or water performance; they are different programmes.
- Ignoring the size tested field, which limits the label's validity.
- Accepting a label referencing a superseded standard edition the code no longer allows.
- Assuming safety glazing labelling and certification labelling are the same mark.