Good Housekeeping tested a variety of hair products in their Beauty Lab to find the winners of the Anti-Aging Hair Awards. To test how those products impact the strength of hair, technicians used a comb fixture on an Instron system. The Good Housekeeping team measured "friction experienced when [the fixture] moved through a wet or dry hair swatch". Simulating what happens in real life instilled confidence in consumers to purchase those winning products.
Instron comb fixture for testing hair products
Here is another example of an Instron system performing a tensile test on hair to determine strength before and after a product is used.