Revision J of the Nadcap Penetrant (AC7114/1) and Magnetic Particle (AC7114/2) Non-Destructive Testing audit checklists took effect this year.
For Aerospace suppliers who have Nadcap accreditation, these latest checklists now include specific questions regarding LED UV-A lamps. To comply, the lamps must be certified by the manufacturer and several additional details must be added to the written procedures regarding their use.
Here is a quick list of those changes, and how you can comply with the new Nadcap audit requirements.
Is there evidence from the manufacturer that validates the correct peak wavelength of the output?
(AC7114/1 Rev J paragraph 3.5.1 and AC7114/2 Rev J paragraph 3.3.1)
Make sure your LED UV lamp manufacturer's certification includes peak wavelength validation and keep your original certification readily accessibly to show an auditor.
The ASTM E3022 certification included with every EV6000 hand-help LED UV lamp shows validation of the peak wavelength in the range of 365 ±5 nm.
If a battery powered UV-A LED lamp is being used, is there a procedure to ensure the correct UV intensity is maintained throughout period of use?
(AC7114/1 Rev J paragraph 5.13.8 and AC7114/2 Rev J paragraph 5.4.8)
If you are using a battery-powered LED UV lamp, then your procedures must define what to do if the UV-A intensity of your lamp drops below 1,200 µW/cm2.
Are UV-A LED flashlights (small battery powered UV-A sources) only utilized for localized inspections (e.g. weld repairs, bore inspections, hard to reach areas)?
(AC7114/1 Rev J paragraph 5.13.9 and AC7114/2 Rev J paragraph 5.4.9)
UV-A LED lamps are very flexible in configuration, so the important thing is to use the right tool for the job. Torches and flashlights are good for small spot inspections and blind holes. But for most inspections, you need a broad beam to find indications consistently and quickly.
Is the minimum acceptable limit 1,200 µW/cm2 and the maximum 10,000 µW/cm2 at 15 inches (38 cm)?
(AC7114/1 Rev J paragraph 5.13.10 and AC7114/2 Rev J paragraph 5.4.10)
Make sure your LED UV lamp manufacturer's certification includes verification of UV-A intensity at 15 inches / 38 cm and keep your original certification readily accessibly to show an auditor.
The ASTM E3022 certification included with every EV6000 shows certification of UV-A intensity at 15 in / 38 cm.
Are the UV light(s) good and in clean condition?
(AC7114/1 Rev J paragraph 5.13.13 and AC7114/2 Rev J paragraph 5.4.13)
This is not intended as a simple housekeeping check.
While mercury-vapor lamps are very simple, LED lamps use electronics so there are different things to look for to make sure the lamp is in good condition.
A white paper check is the simplest way to demonstrate that all LED elements are working and the lamp is performing well.
With flexible configurations, increased safety and elimination of hazardous waste, LED UV-A lamps promise to make fluorescent penetrant testing and magnetic particle inspection faster and more efficient.
Knowing what to look for and how to comply with Nadcap and other industry specification requirements means you can realize and maximize those benefits in your inspection line.