Before every use or each operating day
- Check the instrument identity, status label and calibration due date.
- Inspect the power cord, plug, tubing, glass parts, guards and visible seals.
- Confirm the work area and instrument surfaces are clean and dry.
- Check required water, gas, ventilation, drainage or compressed-air services.
- Run the manufacturer’s start-up or self-check and record abnormal messages.
- Do not operate equipment with unresolved safety damage or failed checks.
Weekly housekeeping and functional checks
- Clean accessible surfaces using compatible materials.
- Inspect doors, lids, hinges, latches, gaskets and moving parts.
- Check fans, vents, filters and cooling paths for obstruction.
- Review temperature, speed, pressure, weight or other control readings for unusual drift.
- Verify that accessories, racks, rotors, probes and cables are present and undamaged.
- Review the fault log and close completed corrective actions.
Monthly or scheduled checks
| Area | Example check | Record |
|---|---|---|
| Performance | Compare indicated values with an appropriate reference where permitted | Observed value, reference and acceptance result |
| Safety | Inspect interlocks, alarms and protective devices using approved procedures | Pass/fail and action taken |
| Utilities | Review voltage, water quality, pressure, drainage or ventilation as applicable | Measurement or inspection result |
| Consumables | Inspect filters, lamps, seals, desiccants, lubricants or fluids | Condition and replacement date |
| Documentation | Review manuals, service reports, calibration and asset records | Missing or expiring items |
Calibration is not the same as maintenance
Maintenance is intended to keep equipment in suitable operating condition. Calibration compares an indicated value with a traceable reference under stated conditions. One does not replace the other. Instruments may also require qualification, verification or performance checks depending on the method and quality system.
Create one controlled record per instrument
- Asset ID, manufacturer, model, serial number and location
- Responsible department and authorised users
- Installation, warranty and service contact information
- Maintenance tasks and approved intervals
- Calibration or verification schedule and acceptance criteria
- Fault history, downtime, parts replaced and corrective actions
- Current status: available, restricted, under repair or retired
When to stop using an instrument
Remove equipment from service when there is a safety defect, damaged pressure or electrical component, failed calibration or performance check, unexplained drift, contamination that cannot be controlled, or any condition prohibited by the manufacturer’s instructions. Label it clearly and prevent unintended use until an authorised person releases it.
Direct technical answers
Frequently asked questions
How often should laboratory instruments receive preventive maintenance?
Intervals depend on the manufacturer’s instructions, usage, environment, criticality, regulatory requirements and fault history. Set and document an interval for each instrument instead of using one schedule for all equipment.
Does preventive maintenance replace calibration?
No. Maintenance keeps equipment in suitable condition, while calibration compares measurements with a reference. Both may be required, along with verification or qualification.
What should be recorded after maintenance?
Record the instrument ID, date, task, observations, measurements, parts used, person performing the work, acceptance result, next due date and any restrictions or follow-up actions.