Understanding the parameters that are used to comply with PA2 are a bit complicated. On the other hand, measuring Dry Film Thickness (DFT) is pretty easy!
BlastOne explains the parameters and explains how to use the Defelsko Positector 6000 DFT gauge in the above video.
OVERVIEW: IN REGARDS TO THE PARAMETERS INCLUDED IN A PA2, THERE ARE 5 COMPONENTS TO UNDERSTAND.
1. Minimum & Maximum Thickness
Coating manufacturers will specify their coatings need to be applied at a minimum or maximum coating thickness which will then warrant the owner of the facility for however many years the manufacturers say. Some coatings may only come with a specification of a minimum DFT, where you would only worry about that number, versus the two numbers in the other situation.
2. PROJECT DIMENSION AREAS
You will need to divide your entire project dimensions into separate Areas. The Areas need to be a minimum of 100 sq ft. Something to keep in mind – Girders and beams measurement requirements vary.
3. GAGE READINGS
Each inspected Area will have 5 randomly selected sports where measurements are taken. Three readings are required to be taken in an area that is 1.5” or smaller in diameter, where the results will be averaged in order to get a SPOT value. The readings are taken by the magnetic instrument.
Five or more SPOTS will be inspected in any AREA. The average value of the gauge readings compromising that spot are equivalent to the SPOTS. These values are able to be between 80% of the minimum DFT specification and 120% of the maximum DFT specification that was determined by the manufacturer.
5. SPOT AVERAGE
The five or more spots that get inspected will be averaged into a SPOT AVERAGE for that whole Area. The average has to comply with the Minimum and Maximum DFT determined by the Paint Manufacturer.
The SSPC PA2 Standards paper.
DOWNLOAD THE SSPC PA2 POSTER
Use our BlastOne Inspecting to SSPC PA2 Standards poster to help with your DFT inspections.