Meaning of 水洗式 other than flush toilet In an article about penetrant testing () I found the following sentence: > **** In this kind of test, a penetrant liquid is used on a surface (in this case a weld area, ) to check if it has defects. Here I read that refers to a flush toilet, but in this context it doesn't make much sense to me. Could it refer to a drainage outlet or something similar? I mean something used during the test to collect the dripping of penetrant liquid? Thank you for your help!

**** does not refer to a flush toilet itself, but it refers to a method/system.

* : water
* : wash / clean
* **: -type**



So (literally "water-wash type") can refer to anything that can be washed, flushed or wiped with water. In layman terms it usually refers to a type of toilet, but in this case, it describes a type of . The Wikipedia article you linked has a good explanation for this:

> The excess penetrant is then removed from the surface. The removal method is controlled by the type of penetrant used. **Water-washable** , solvent-removable, lipophilic post-emulsifiable, or hydrophilic post-emulsifiable are the common choices.

So:

>
> The penetrant must be water-washable and applied with brushes, ...