My understanding is that effectiveness is due in part to the acidic vinegar having a neutralizing effect on the alkaline urine. 

Then we hosed it down and used some acid.

I cleaned hideous toilets back to virtually new in a few minutes using pool acid.

Many people sleep on their sides to mimic the fetal position but the problem is you toss and turn because pressure is put on the shoulder.With a motorized bed you can elevate the legs which takes pressure off of the spine and back and with the upper body elevation you keep reflux from happening from the stomach into the throat which also helps the sinuses drain properly instead of pool and swell the turbinates at night causing congestion and difficulty breathing.The zero gravity position from a motorized bed mimics the fetal position but opens up the lungs for better breathing and keeps the acid down in the stomach plus since you are not on your side the pressure is not on the shoulders.When you first try it there is some getting used to as your body has been out of whack for so long.    

If stain remains, apply rust remover or oxalic acid solution. 6.

It just has enough accumulation of sulfuric acid to cause issues in an enclosed space. 

A quick acid test, if you will?

Yes, I understand that the 2% rule is a quick and dirty acid test, not a proforma, but I'm curious how ya'll use it practically in different scenarios.

It's about $500 plus $150 if you want them to throw in 10 gal of acid (which you will want that).

The cheapest option (other than nothing) would be to make a cut in the middle and remove the old, then acid stain the driveway so it all matches.