What can black light with a proper functioning filter in place cause permanent damage to during fluorescent penetrant inspection?

In the context of fluorescent penetrant inspection, black light, or ultraviolet (UV) light, is used to detect surface flaws in materials. When paired with a proper functioning filter, the UV light is directed to highlight flaws without causing harm.

Human eyes can be particularly sensitive to UV light, so proper safety precautions, such as wearing UV-protective glasses, are often advised during inspections. However, the question focuses on situations where damage could occur. With a functioning filter, the potentially harmful wavelengths of UV light that could cause eye damage are effectively blocked, making it safe for human observers.

Electrical equipment is generally not prone to permanent damage from black light during this type of inspection unless there’s an unusual situation involving direct exposure or certain sensitive electronic components.

Plastic parts, depending on their composition, can degrade or discolor when exposed to UV light over prolonged periods. However, during the actual process of fluorescent penetrant inspection, a properly functioning filter minimizes the risk of such damage, thereby not causing permanent damage to plastic parts during the short duration of the inspection.

Given the context that a functioning filter is in place, the most accurate choice is that none of the mentioned items would experience permanent damage during the process, as appropriate safety measures are taken. Thus