Impact energy scales with velocity. Gauge at the nozzle, not only at the compressor. Hose drop and a worn orifice fake a high pot gauge.
Order-of-magnitude field values
| Nozzle PSI | Velocity (guide) | Impact | Typical profile band |
|---|---|---|---|
| 60 PSI | ~140 m/s | Moderate | 25-40 micron |
| 80 PSI | ~180 m/s | High | 50-75 micron |
| 100 PSI | ~220 m/s | Very high | 75-100 micron |
| 120 PSI | ~250 m/s | Extreme | 100 micron+ |
Prove the profile with a BLAST APEX dial gauge (ASTM D4417) or replica tape. Do not assume 100 PSI gave Sa 2.5.