17.1 Equipment Maintenance, Calibration Schedules & Clinic Safety

Equipment Maintenance, Calibration & Clinic Safety

Reliable measurements depend on equipment identity, condition, approved cleaning, calibration, software configuration, and staff competency. Build the maintenance plan from the device's current instructions for use, facility policy, clinical-engineering schedule, and applicable regulation. A schedule copied from another model is not evidence.

Pre-use and routine checks

Before use, confirm the correct device and accessories. Inspect housing, power cord, plug, footswitch, battery indicator, charger, cables, connectors, wheels, locks, chin rest, forehead strap, guards, optics, and disposables. Run the manufacturer-required self-test. Verify date and time when they affect image comparison. Check that emergency stop controls and isolation features are accessible.

Handheld instruments need charged batteries, clean contacts, undamaged housings, and a backup plan. Rechargeable cells are replaced according to performance and the manufacturer's limits, not an invented calendar. Remove leaking, swollen, overheating, or damaged batteries from use and follow the approved disposal process.

If a device is dropped, exposed to liquid, produces smoke or unusual heat, fails self-test, gives implausible values, or has a damaged patient-contact surface, stop using it. Attach an out-of-service label, prevent accidental reuse, document the event, and notify the designated service group. Only authorized personnel open housings or perform repairs.

Optical surfaces and patient-contact parts

Dust is removed with the approved noncontact method before wiping. Use only specified lens paper, cloth, fluid, and motion for coated fundus lenses, camera objectives, OCT apertures, slit-lamp optics, and prisms. Apply fluid to the approved wipe rather than flooding the instrument unless the instructions say otherwise. Separate optical cleaning from high-level disinfection of a patient-contact surface.

Inspect lenses and prisms for chips, coating damage, cracks, deposits, and clouding. Clean chin rests, forehead straps, handles, fixation targets, and controls using compatible products and required wet-contact time. A disinfectant can be microbiologically effective yet mechanically destructive to a particular device.

Calibration and quality control

Record device identifier, date, test method, reference device or phantom, expected range, observed result, staff member, and corrective action.

For the Haag-Streit AT 900, the monthly check uses its test weight at measuring-drum positions 0, 2, and 6. The current instructions specify −0.05 to +0.05 at zero, 1.95 to 2.05 at position 2, and 5.9 to 6.1 at position 6. Another model may use different tools or limits. A failed device is removed from service; staff do not apply informal correction factors to patient results.

Automated perimeters, fundus cameras, ultrasound systems, OCT/OCT-A platforms, lasers, and cryotherapy units use manufacturer-defined self-tests, reference targets, service intervals, and environmental limits. Quality control includes recognizing drift in image scale, focus, illumination, segmentation, fixation monitoring, probe performance, output verification, or system warnings. Escalate rather than bypass a warning.

Emergency and environmental readiness

Check emergency eyewash, crash cart, oxygen, suction, AED, spill kits, and emergency medications at the frequency assigned by the facility plan. Record seal status, expiration, battery readiness, accessibility, and inspection result. Test an eyewash according to the governing safety program and keep access unobstructed.

Monitor storage temperature for medications and supplies according to each product label. Review minimum and maximum logs and respond to an excursion through the designated quarantine and pharmacy process; do not return a product to use based on appearance alone. Product-specific labels control refrigeration, freezing protection, light protection, and allowable room-temperature exposure.

Use first-expire-first-out inventory rotation, retain lot and expiration traceability when required, and keep sufficient emergency and procedure supplies without overstocking. Clinical readiness includes charged equipment, compatible disposables, updated software under change control, accessible instructions, trained users, and a documented backup workflow.

Service records

Keep maintenance, calibration, repair, software, recall, and incident records with the device. After repair, verify return-to-service authorization and required performance tests. Report recurring failures and possible adverse device events through the organization's safety and regulatory process.

Recall, software, and downtime control

Device safety includes software version, cybersecurity notices, accessories, and recalls. Match the model and serial number to a recall or field-correction notice, quarantine affected equipment when instructed, and document the manufacturer's remedy. Software updates require change control and post-update function checks; never install an unapproved update during patient care.

Every critical system needs a downtime plan. Staff should know how to preserve images, label laterality, document results, contact service, and move patients when the network, PACS, power, or device is unavailable. After repair, authorized personnel complete required performance verification before return to service. Trends such as repeated self-test failure, drifting measurements, intermittent cables, or recurring artifacts are reported even when a reboot temporarily clears the symptom.