The cooking process should bring the water to a full rolling boil for at least one minute before adding the food item (for example, making pasta). If the water will be at a slight boil for a long time, then this will also be protective. For example, you may be cooking beans or boiling chicken for 10 - 20 minutes.
While it varies based on the type of products used and the efficiency of the stylist, it usually takes around 1 1/2 to 2 hours to get hair colored at a salon, according to a poll by Glamour magazine....
How Long to Wait to Re-Dye Hair. When coloring your hair doesn't go exactly as planned, don't panic. Although you can re-dye hair within a day, it's best to understand what your hair has gone through and how to help prepare it for even more changes.