If a lotion's pH level is too low it can lead to irritation; if it is too high, it can cause irritation and upset the pH balance of skin. This is why using a reliable pH meter is so important.
Choose Digital Over Paper
While pH paper testing strips have been used for years, your best bet is a digital meter. The pH Meter from SoapCrafters.com is lightweight and works whether the lotion contains dye or not.
Soap Crafter.com's pH Meter is pocket-size at 6.2 inches long. The electrode at the end sticks out 3.15 inches and it has a pH range from 0 to 14.0 pH. It is powered by one 9-volt battery, which is included.
The pH meter features a digital display and automatic temperature compensation. It's lightweight and comes with a sturdy carrying case. It also comes with a calibration screwdriver and solution.
The SoapCrafter.com pH Meter sells for $48.95, as of February 2011, and ships via UPS or USPS.