| Safety | Guarding and interlocks | A fully enclosed coating zone with an interlocked access door that stops motion when opened. | High | Confirm that the door cannot be opened during hazardous movement and that the machine restarts only after a deliberate reset. | Inspect switches, hinges, seals, and emergency-stop circuits during scheduled safety checks. |
| Safety | Emergency stop system | Clearly labeled, easily reachable emergency-stop buttons with a documented reset procedure. | High | Test the stop function at installation and verify that the machine does not automatically restart after power recovery. | Perform periodic functional tests and replace damaged or difficult-to-operate actuators. |
| Safety | Ventilation and solvent control | Connection to suitable local exhaust ventilation when using volatile solvents, with compatible ducting and containment. | High | Review solvent compatibility, airflow requirements, exhaust routing, and the laboratory’s chemical-safety assessment. | Check filters, airflow, tubing, seals, and collection containers for blockage, leakage, or degradation. |
| Safety | Electrical protection | Grounded construction, overload protection, suitable ingress protection, and electrical components rated for the laboratory environment. | High | Request electrical schematics, rated voltage and current, protective-device requirements, and applicable conformity documentation. | Inspect cables, connectors, grounding, cooling vents, and control cabinets for wear or contamination. |
| Safety | Chemical and thermal compatibility | Wetted parts, tubing, seals, and work surfaces compatible with the coating formulation and operating temperature. | High | Compare all materials in contact with the coating, solvent, substrate, and cleaning agent against supplier compatibility data. | Replace swollen, cracked, brittle, discolored, or softened components before they affect containment or coating quality. |
| Accuracy | Coating-speed control | Closed-loop or digitally controlled speed with a stated repeatability specification appropriate to the process. | High | Run repeated tests at low, medium, and high speeds and compare actual speed with the displayed setpoint. | Keep drive components clean, inspect belts or couplings, and verify speed periodically with a calibrated instrument. |
| Accuracy | Film-thickness uniformity | Uniformity suitable for the application, commonly verified by a defined measurement method rather than by visual inspection alone. | High | Request sample data across the coated width and specify the acceptance method, sample count, and environmental conditions. | Clean applicator surfaces, maintain level alignment, and replace worn blades, rods, slots, or coating heads. |
| Accuracy | Applicator alignment | Rigid, adjustable alignment with repeatable positioning and minimal lateral or vertical play. | High | Check parallelism, edge-to-edge gap, substrate tracking, and repeatability after removing and reinstalling the applicator. | Inspect guides, clamps, bearings, and adjustment mechanisms; remove dried coating from contact surfaces. |
| Accuracy | Wet-film measurement capability | Compatibility with wet-film gauges, gravimetric checks, optical measurement, or another validated thickness method. | Medium | Confirm that the selected measurement method covers the expected coating range and substrate type. | Clean measurement tools after use and maintain calibration records for gauges and laboratory instruments. |
| Accuracy | Temperature and environmental control | Stable substrate or drying conditions when viscosity, evaporation, or curing is temperature-sensitive. | High | Determine whether temperature, humidity, airflow, or drying time must be monitored and recorded for each run. | Calibrate sensors, clean heaters and fans, and verify airflow or temperature uniformity at defined intervals. |
| Process Control | Recipe storage and traceability | User access control, recipe versioning, run identification, and exportable process records. | Medium | Verify whether speed, gap, temperature, drying time, operator, date, and material lot can be recorded and retrieved. | Back up recipes and audit logs; control software updates and document any parameter changes. |
| Process Control | Scale-up relevance | Adjustable parameters that represent the intended production process, including coating method, substrate width, and drying conditions. | High | Compare laboratory shear, web tension, coating speed, drying load, and formulation volume with future scale-up requirements. | Maintain a documented process window and record deviations that could affect scale-up conclusions. |
| Maintenance | Cleaning access and changeover | Tool-free or low-tool access to coating heads, trays, reservoirs, rollers, and splash-protection surfaces. | High | Time a representative cleaning and changeover procedure using the actual coating formulation and cleaning agents. | Follow written cleaning intervals and prevent dried residue from accumulating around moving or sealing components. |
| Maintenance | Wear-part availability | Clearly identified replacement parts with specifications, expected service intervals, and reasonable lead times. | Medium | Obtain a parts list for blades, seals, tubing, filters, belts, bearings, lamps, and sensors where applicable. | Keep critical consumables in stock and record replacement dates, causes of failure, and operating hours. |
| Maintenance | Calibration and service documentation | Documented calibration points, service procedures, acceptance tests, and maintenance logs. | High | Confirm which parameters require calibration and whether certificates or traceable reference standards are available. | Set risk-based calibration intervals and retain certificates, service reports, and corrective-action records. |
| Usability | Operator interface and training | Clear controls, role-based access where needed, alarm messages, and training materials for routine operation. | Medium | Evaluate whether a trained operator can load, coat, stop, clean, and recover from common alarms without unsafe workarounds. | Review training after software changes, process changes, incidents, or extended periods without use. |
| Facility Fit | Footprint, utilities, and ergonomics | Adequate clearance, stable bench or floor support, suitable power, ventilation, compressed air, and waste handling if required. | High | Check dimensions, access routes, noise, heat output, utility connections, operator reach, and service clearance. | Keep service areas unobstructed and inspect utility connections for leaks, loose fittings, or deterioration. |
| Selection Decision | Acceptance testing | A written site-acceptance test using representative substrates, formulations, operators, and predefined quality criteria. | High | Define measurable pass/fail criteria for safety functions, speed, thickness, uniformity, repeatability, cleaning, and data records. | Use acceptance results as the baseline for future preventive maintenance and process-performance reviews. |