A coating specification usually contains a handful of hold points where work must stop until an inspector signs off. Crews that plan around them keep moving. Crews that discover them keep waiting.

The standard sequence

Pre surface preparation. Confirming steel condition against ISO 8501-1 initial rust grades, weld quality, edge treatment and removal of oil and grease. Sharp edges and weld spatter must be dressed before blasting, because coating pulls thin over them regardless of how well it is applied afterwards.

After surface preparation, before priming. The busiest hold point: visual cleanliness against Sa 2.5 comparators, surface profile measurement, dust testing to ISO 8502-3, and soluble salt testing where specified. Environmental conditions are logged here too. Our Sa 2.5 guide covers each check.

After each coat. Wet film checks during application, dry film thickness to SSPC PA 2 after cure, holiday or pinhole detection on immersion systems, and visual inspection for runs, dry spray and misses.

Final acceptance. Total system thickness, adhesion testing where specified, appearance, and completeness of the documentation package.

What delays a hold point

Almost always paperwork rather than workmanship. Calibration certificates for gauges out of date. Environmental logs not maintained through the shift. Batch numbers not recorded against areas. Inspectors cannot sign what cannot be evidenced, and rectifying records after the fact is far harder than keeping them.

Practical preparation

Read the specification before mobilising and list every hold point with the evidence each requires. Confirm instrument calibration before arrival on site. Nominate one person responsible for records per shift, because shared responsibility means nobody does it. Give the inspector reasonable notice rather than calling for immediate attendance, and stage work so that a hold point on one area does not stop the whole crew.

Where third party inspection changes things

On oil and gas and marine work an independent inspector adds formality but rarely new requirements. Their presence tends to expose weak record keeping quickly, which is why the discipline described in our DFT measurement article pays back across the whole project.

MENA Industrial Supplies supplies coatings with the data sheets and batch documentation needed to satisfy inspection records.