I agree with Rennhack, it depends on the particular type of contamination, or the materials the contamination is combined with, ( dust, dirt, grease, acids, alkali, solvents, glue ). Some of the products mentioned in the initial posting would not be my first choice, my second either. It's always great to have a one stop cure all, but the standard decontamination methods have been proven for decades. Normally, soap and warm water will resolve 99 % of your contamination cases. As well as being an effective cleaning agent, the worker will feel more comfortable when they see that it is as simple as washing their hands, just like they do at home!
If it doesn't work after 3X , focus on the skin condition and any signs of foreign residue. If grease is present, a product such as dawn can be used, straight without water, then rinsed. This will usually cut the grease and even some types of tape residue. If the residue still persists, a little, ( Very Little ), waterless hand cleaner could be used in localized areas.
Tide was mentioned and it is very effective, in the powder form. Powdered Tide, contains Titanium Dioxide, a great Oxidizer! Most people assume it should be used like a soap, wash and rinse. This isn't the case, it should be mixed into a thick paste with water, then applied to the area for a couple of minutes, until it starts to dry. It may seem a little ridiculous but this stuff is actually fairly aggressive. It is oxidizing the thin layer of outer skin! I have used this method several time and the workers involved seemed to have little concern with the product. After all most of them washed their clothing in the stuff!
Potassium Permanganate is an oxidizer and should only be used if you are trained. I have only seen this product used twice in the past 25 years. Once by myself and once by an impatient Engineer, who thought he knew better! The Engineer incident, was one of those," Where is the camera when you need it", moments! He picked the bottle up and applied it to his thighs and crotch, in the shower. In a short time he realized that the purple wasn't coming off! After we managed to get chemistry to mix us up a batch of neutralizer, the Engineer's last words were, " Thanks, It was starting to get Real Tingely"! This product also has a very specific negative reaction with many other chemicals and will waste a demineralizer bed in a heart beat!
Before using any product, READ the LABEL! Make sure it has been proven for use on a persons skin. Make sure it won't cause you an even bigger problem. If a product's label contains the words, Petrolium Based, or gives a VOC range, I wouldn't even consider it!
Keep the worker involved in the process you are using and allow him to reason it out. I have seen a simple decontamination incident run for weeks, because the person wasn't given any explaination as to what was used, or why!
After you have completed the decontamination, make sure you follow up with some form of skin conditioner, even if you only used soap and water.