Is there a way to test the actual PH of your hair?!?!?

I've been hearing a lot of talk about the Ph of products and assuring that your hair remains in a specific range to be considered "balanced". Now, from my understanding, the "Ph balance" of hair is between 4.5-5.5. I also understand that the difference between 2 numbers or one step up or down on the PH scale is astronomical! You actually multiply or divide by 10 (depending on which way you're moving on the scale). So, a product which has a Ph of 4 is really -> (10,000) and 5 is really -> (1000). That seem like a huge difference to me. I'm sure the same would be true between 4.5 and 5.5 (the difference is 1).

To say that any product I use that falls between 4.5-5.5 seems to be a pretty big deal to me. What If my hair is on the low end of the spectrum at 4.5, it may be harmful to use a product that's 5.5.... right? Now I have heard that this range, 4.5-5.5 is considered the "no harm zone" for hair. Meaning that it either adds what the hair needs or leaves it alone to keep it balanced. :-/

The PH range for hair given, 4.5-5.5 was establised 2 wasys... 1. by the Ph of Sebum (the oil/ our hair naturally produces), and/or 2. when a single strand of hair is dissolved in a liquid. Sooooo my question is...

Does anyone know of a way to test the PH of your hair? I want to know the exact ph of the sebum I naturally produce so that I can use products with or as close as possible to that ph in hopes of having optimal "health" for my hair.