What practice should be avoided during a penetrant test?

During a penetrant test, applying the emulsifier with a brush is generally discouraged because it can introduce contaminants or cause uneven application, which may lead to inconsistent results. A brush can also inadvertently disturb the penetrant due to physical contact, potentially affecting the integrity of the inspection process.

In penetrant testing, it is crucial to maintain a controlled environment where the penetrant can be evenly distributed and effectively drawn into any surface-breaking flaws. Utilizing methods that minimize the risk of disturbing the penetrant ensures accuracy in detecting defects.

In contrast, using multiple emulsifiers is sometimes a part of the testing process, and saturating the specimen with penetrant is necessary to allow deep penetration into flaws. Leaving the penetrant on for an extended period is sometimes acceptable as it can improve sensitivity by allowing more time for the penetrant to seep into any discontinuities, provided that the manufacturer's recommendations are followed.