Polychlorinated Biphenyl - How to Protect Your Products?

When looking at your pre-existing rig, see how concealed the PCB is inside of its housing. If the PCB is snug as a bug in a rug inside of its little home than you can get away with a simple spray of coating which will just be a back up in case the main housing unit doesn’t do its job to the best of its abilities.
 
If your housing is not the main source of protection for your PCB than a thicker, more durable resin should be applied to act as a superior protective layer.
When looking over the difference between coating and resin you should take into consideration their consistencies.
 
Coating, often thin and clear in color, can not be applied as thickly as resin can. The coating also tends to have a shorter drying time and a longer shelf life. Resin, on the other hand, can be applied in thick globs, which will weight the product down but provide an increased barrier against abrasion and dirt. Resin also cannot be applied via spray which makes the application process a bit longer and slightly more tedious.