Safety, Environment, and Jobsite Practices
Hazards of preparation and application
Abrasive blasting generates respirable crystalline silica; the controls are containment, dust extraction, and appropriate respiratory protection under the applicable occupational exposure rules. Blasting or removing old coatings may release lead, chromates, or other toxics, triggering air monitoring, hygiene facilities, and regulated waste handling. Solvent-containing coatings create flammable atmospheres: control ignition sources, bond and ground equipment, and monitor the lower explosive limit (LEL) before and during work in confined spaces.
Confined spaces
Entry requires an entry permit, atmospheric testing (oxygen roughly 19.5–23.5%, flammable gas below 10% LEL, and acceptable toxic gas levels), continuous or periodic ventilation, an attendant, a rescue plan, and communication. Solvent vapors are often heavier than air; test at multiple levels, not just at the top of the space.
Environment and jobsite practice
Contain blast media and debris; dispose of waste per regulation; prevent spills reaching drains and waterways; manage VOC-emitting activities consistent with permits. Scaffolding, access, fall protection, and housekeeping are inspection concerns too - you cannot inspect safely from an unsafe position, and you should not walk under suspended loads or enter unventilated spaces to "take one quick reading."
Traps
Questions test whether ventilation after a solvent application is measured (not assumed), whether a high-voltage holiday detector is used in a potentially explosive atmosphere (it must not be), and whether the inspector has authority to stop unsafe work - the answer is generally yes, and the stop must be documented and escalated.
Rule of thumb
Test before entry, ventilate before testing, and re-test continuously. Never let production pressure buy a reading you did not actually take.