Testing Chlorine stength

[salvationarmy]

I use NaOCl 10.5% and HCL 31.45%. I just recently added bleach a couple of times, and got much less than the expected change in FC, and CC remained steady. Can someone recommend a safe and simple titration or other method to test the NaOCl strength? It's been awhile since I had chemistry. I have a K-2006 test kit and no other means to measure pH.
Thanks,
Mike

 

[JasonLion]

There is a procedure for doing this described in this topic and that topic also lists the specialty Taylor kits you can use to get more precise results.