moisture detection electrical impedence meter

Tools & Techniques for Measuring Coating Quality – Part 2: Moisture Detection

This is Part 2 of a 2-part series describing the instrumentation used to inspect the quality of cleaning and painting.  Part 1 described the instruments used for determining the quality of cleaning and paint.  Part 2 addresses moisture detection.  The moisture content of the concrete should be determined prior to painting. In the author’s experience, moisture within the substrate is a leading cause of coating failures on concrete.  If the moisture is elevated, the source(s) should be identified and...

measuring coating quality

Tools & Techniques for Measuring Coating Quality – Part 1 – Cleaning and Painting

When you spend money on a product or service, you expect quality, regardless of the cost.  If you purchase the most inexpensive Chevrolet that is made, you still expect quality.  While the braking system in the Chevrolet may be less sophisticated than a Mercedes, the brakes better work and exhibit quality commensurate with its design.  You expect the parts and installation to meet all of the standards imposed by the manufacturer for that class of vehicle. Expectations of quality for...

peak density optical grade replica tape

Measuring Peak Density Using Optical Grade Replica Tape

Introduction Most industrial and marine protective coatings rely on a mechanical bond to the substrate to remain attached while in service. This bond is generally provided by a surface profile or anchor pattern that is imparted into the surface prior to application of the coating system and effectively increases the surface area of the substrate (e.g., steel). A surface profile is typically generated by abrasive blast cleaning; although some types of rotary impact-type power tools can also create a surface...

Localized Assessment of Air Leakage in Building Air Barriers

ANSI/ASHRAE/IES Energy Standard 90.1-2010 and the 2012 International Energy Conservation Code require that building envelopes be designed to limit uncontrolled air leakage into and out of buildings. Air leakage in buildings is controlled at the time of construction by installing air barrier systems.  ASTM E1186-17, “Standard Practices for Air Leakage Site Detection in Building Envelopes and Air Barrier Systems” defines an air barrier system as “a system in building construction that is designed and installed to reduce air leakage...

surface soluble salt measurement

Surface Soluble Salt Measurement – Conductivity Verses Ion-specific Methods of Analysis

Chemical contaminants on a surface can include chlorides, ferrous ions, sulfates and nitrates, among other types of soluble salts. Chloride may come from deicing materials or marine/coastal environments, ferrous ions are a by-product of corrosion, sulfates can be airborne, particularly in industrial environments (e.g., coal-fired power plants) and nitrates may come from the soil (e.g., fertilizers). These chemicals are deposited onto surfaces while the structure is in service, or during transportation of new steel to the fabrication shop, or...

coating hardness

Measuring the Hardness of Applied Coatings

Introduction The hardness of a coating material is a relative property that may be interpreted in a variety of ways by different industries that use coating/lining materials.  While hardness testing is frequently used to assess the degree of cure, they can also be used to measure hardness properties formulated into coatings.  The absolute hardness of a coating is not always the ultimate goal of the formulation, and an increase in hardness can be accompanied by brittleness or a decrease in...

replica tape

Differences in Surface Profile Measurements: ASTM D4417- Method B vs. Method C

What is Surface Profile and Why is it Necessary? Surface profile is defined as a measurement of the maximum peak-to-valley depth created by abrasive impingement against a surface during abrasive blast cleaning operations, or by an impact-type power tool. During abrasive blast cleaning, the mass of the abrasive and the velocity of the abrasive movement created by compressed air generates kinetic energy (the abrasive can reach speeds of over 600 miles per hour as it exits the blast nozzle). When...

coatings inspection instrument calibration

Calibration, Verification of Accuracy and Adjustment… Synonyms or Differences in Terminology?

“Do I have to maintain inspection gage calibration and certification?  Why don’t they retain their calibration over time? Do I need to verify gage accuracy on a regular basis? How often? What is the difference between calibration and verification of accuracy?” These are common questions in the coatings industry.  A simple answer is that without routinely calibrating/certifying coating inspection gages using standards traceable to a national metrology institution and verifying the accuracy of your equipment prior to use, the gages only reveal...

base metal reading

What is a Base Metal Reading and How Does It Effect Coating Thickness Measurements?

For many in the health care/fitness industry, BMR is an acronym for basal metabolic rate. Sorry to disappoint if you thought this would be a health science article about expending energy. Rather, this article is about a different BMR: Base Metal Reading. We’ll describe what it is, its significance, how to obtain it, and how it impacts coating thickness. Introduction to Coating Thickness Standards There are two common industry standards that govern measurement of coating dry film thickness on metal substrates,...

cross hatch tape coatings adhesion

Coating Adhesion Testing using Knife/Tape Methods

Introduction Adhesion is an important physical characteristic of applied coating films and systems, and testing is frequently used as an indicator to whether an adequate bond exists between the substrate and primer (first coat) and/or between coats in multiple coat applications.  Adhesion testing may be a requirement of a coating specification, or may be used for coating system performance qualification in a laboratory.  Adhesion testing is also a valuable indicator for determining the integrity of coating systems that have been...