Method A: Visible Penetrant Water Washable

Guide to Method A processing per ASTM E-1417.

1. Pre Clean The Surface

Use Met-L-Chek® E-59A, R-503 or R-504 to remove oil, grease and other contaminants from the test surface. The test surface must be clean, dry, and at a temperature of 40-125°F (4.4-52°C) before penetrant is applied.

Products to Use: 

E-59A, R-503, R-504:

2. Apply Penetrant

Apply Met-L-Chek® penetrant using spray, immersion, or wipe on. Wait a minimum of 10 minutes; 20 minutes if temperature is between 40-50°F (4.4-10°C) before proceeding to the next step.

Products to Use:

VP-30, VBP-300

3. Wash

Wash the part.

  • Water Temperature: 50-100°F (10-38°C).
  • Water pressure: < 40 psi (< 275 kPa).
    • If a hydro-air nozzle is used, limit pressure to < 25 psi (< 172 kPa).
  • Wash Distance: > 12 inches (>30 cm).
  • Wash Time: Only long enough to remove surface penetrant under white light.

For Water-Based Developers go to step 3.A

For Non Water-Based Developers skip to step 3.B

3.A Water Based Developers

Apply Met-L-Chek® D-78B developer prior to drying.

  • Dry Time: only long enough to dry surface.

Products to Use: 


3.B Non-Water Based Developers

Dry the part to be inspected and then apply Met-L-Chek® D-70 developer.

  • Dry Time: only long enough to dry surface.

Products to Use: 


4. Inspect

Wait a minimum of 10 minutes before inspection.

  • Use illumination of > 100 foot candles (>1100 lux/m2) to inspect.