How is profile reading measured according to standards?

Profile reading is a critical part of surface preparation in the application of coatings, as it assesses the texture of the surface to ensure optimal adhesion of the paint. According to established industry standards, accurate measurement of profile readings is essential for maintaining quality control during the coating process.

The correct option indicates that profile readings should be taken every 200 square feet within the first 1000 square feet of surface area, with additional readings required for every 500 square feet thereafter. This systematic approach ensures that an adequate number of measurements are taken to evaluate the surface profile adequately, as it can vary across the entire area. The guideline emphasizes the importance of obtaining sufficient data points to represent the surface conditions accurately.

In contrast, the other options either suggest larger increments for readings or a minimal approach, which could lead to insufficient assessment of the surface texture. This could potentially result in areas with poor adhesion performance going undetected, increasing the risk of coating failure. Therefore, the structured frequency of readings provided in the correct answer is essential for ensuring thorough and representative evaluation according to standards.