Problem Solving Forum
January 20 - January 24, 2014
Is it practical to use black light to check for dirt or other foreign matter during surface preparation inspection?
Selected Answers
From
Larry Pitre of CBI on
January 27, 2014:
In addition to my previous response, ASTM A-380 St ...read more
In addition to my previous response, ASTM A-380 Standard Practice for Cleaning, Descaling, and Passivation of Stainless Steel Parts, Equipment, and Systems contains specific details on use of black light for surface inspection:
7.3.2 "Black Light Inspection is a test suitable for the detection of certain oil films and other transparent films that are not detectable under white light. In an area that is blacked out
to white light, inspect all visible accessible surfaces with the aid of a new, flood-type, ultraviolet lamp."
However, ASTM A-380 also indicates that "The test will not detect straight-chain hydrocarbons such as mineral oils."
Use of Black Light for inspection of surface preparation is a useful tool and can be a required step for certain industries.
From
Larry Pitre of CBI on
January 27, 2014:
Yes, black light is an improved means of detecting ...read more
Yes, black light is an improved means of detecting
invisible contamination on apparently clean surfaces.
It is a quick, cheap, effective, and easy method to improve and maintain cleanliness prior to coating products.
UV light provides an instant visual check of surface cleanliness; allows for monitoring the effectiveness of cleaning procedures and chemicals; identifies problem areas not cleaned properly, which can then be re-cleaned to the required standard ensuring dirt and chemicals are removed; and trains new and existing staff on how to clean to higher standards.
From
Michael Halliwell of Thurber Engineering Ltd. on
January 24, 2014:
I don’t know that it is a matter of being blind, D ...read more
I don’t know that it is a matter of being blind, David, but rather a question of contrast. You can see lint on your clothes under regular light, but it stands out considerably more under blacklight. Perhaps that’s what sparked the question?
From
david cuthbertson of Eptec Group on
January 22, 2014:
What...Are you blind?
Think about why you would u ...read more
What...Are you blind?
Think about why you would use a different light spectrum...Would it be for non-visible contaminants?