Each laboratory section is responsible for training employees in the proper use, maintenance and safety of all instruments and equipment. Section-specific guidelines should be established in the sections' standard operating procedures based on the specific laboratory equipment and instruments, but the following guidelines for common instruments must be followed.

Microscopes

  • All Laboratory of Pathology microscopes, clinical and research, are maintained and serviced by Barber Optics, Columbia, MD.

  • Service technicians perform cleaning and preventative maintenance (PM) to ensure optics are aligned, lenses clean and oil free at least annually for bright-field microscopes.

  • Fluorescence microscopes are also monitored to ensure sufficient light source intensity and appropriate filters and slides are used and appropriate.

  • LP's service agreement with Barber Optics includes biannual PM on all microscopes.

  • Preventative maintenance and service repair records are maintained in the Clinical Manager's office.

  • Trained technicians are available to LP staff to service or repair issues with LP microscopes. Contact 301-596-2406 or email info@barberoptics.com to request service if necessary. 

Thermometers 

  • An appropriate thermometric standard device of known accuracy must be used to monitor temperature-dependent instruments and environments in accordance with manufacturer's instructions. Refer to Maintenance and Function Checks policy for Temperature Checks guidelines.

  • Thermometric standard devices must be recalibrated, recertified or replaced prior to the expiration date of the guarantee of calibration. If no date of expiration is listed, the expiration date will be three years from the date certified/calibrated. Thermometers should be periodically evaluated for damage, and discarded if needed.

  • Non-certified thermometers must be checked against an NIST-certified or traceable standard device before initial use and every three years thereafter. The expiration date of this calibration verification will not exceed the expiration date of the standard device used.

  • Certificates of calibration or inhouse validations of non-certified thermometers demonstrating validation with a NIST-certified or traceable device must be retained for the life of a thermometer. 

  • Note: NIH Mercury Abatement Program
    • The NIH Department of Occupational Health and Safety (DOHS) has developed a mercury policy that aims to replace mercury-containing equipment with “greener” products where possible. 
    • Although the Laboratory of Pathology has been deemed mercury-free, staff should be knowledgeable of the NIH Chemical Hygiene Plan, Mercury Spills. 
    • Additionally, the NIH Waste Disposal Guide provides instructions on how to discard thermometers and other items that might contain mercury on the NIH campus.

Refrigerators and Freezers 

  • Place a sign on each unit stating the unit is used for "Laboratory Use Only".
  • Place a biohazard sign on each unit that may contain biological specimens.

  • Refrigerator and freezers containing reagents or patient/client specimens must have their temperatures checked and recorded daily. “Daily” means every day (7 days per week, 52 weeks per year).

  • The laboratory must define the acceptable temperature ranges for all refrigerators and freezers. The temperature range must be documented on the temperature log. Temperature and min/max logs can be found on the Forms and Checklists page. 

  • If temperature(s) are found to be outside of the acceptable range, the laboratory must record appropriate corrective action, which may include evaluation of contents for adverse effects.

  • A minimum-maximum thermometer may be used to monitor temperatures over weekends and holidays when it is not practical to record the temperatures on those days. If a minimum/maximum thermometer is used to perform continuous monitoring of temperatures between daily temperature readings or following a laboratory downtime (e.g. laboratory closure for weekend or holiday), both the low and high temperatures must be recorded. To ensure correct temperature readings, the minimum/maximum thermometer device must be reset prior to the monitoring period.

Centrifuges 

  • Do not operate centrifuges unless the covers are closed. Keep hair, beard, neckties, hair ribbons, hair braids, or other dangling items out of the way.
  • Do not centrifuge uncovered tubes containing specimens or flammable liquids. Use caps or parafilm.
  • Before centrifuging check the integrity of tubes and tube holders.
  • When the centrifuge is in operation, the lid must always be closed. If a noise or vibration begins, stop the centrifuge immediately and check for improper balancing of loads, caps, and rotors.
  • Tubes used in angle head rotors must never be filled to the point where the liquid is in contact with the lip of the tube when placed in the rotor.
  • Avoid decanting, no matter what type of centrifuge tube is used. If unavoidable, wipe off the outer rim afterwards with a disinfectant; otherwise, the fluid on the outer rim will spin off as an aerosol.
  • When centrifuging infectious agents, safety carriers (carriers with individual screw caps) or rotors that are sealed shut should be used.
  • Centrifuges should be clean and free of spills. The holders (cups) and centrifuge should be cleaned as needed. The cups should first be disinfected and then washed in warm soapy water and scrubbed with a nylon brush.
Centrifuge Maintenance 

Each section must have a documented protocol and schedule for maintenance of centrifuges (cleaning, changing brushes, etc.). For centrifuges with safety mechanism preventing the opening of the lid while in operation, the checks of rpm should be performed only by an authorized service representative of the manufacturer or an appropriately trained clinical engineer.

1.  Daily Maintenance

As the centrifuges are being used, they are inspected for spills.  After a spill, they are cleaned with a freshly prepared 10% bleach solution as soon as possible with special emphasis on difficult to reach areas.  Positioning of the speed and temperature settings are also noted with each use.

2.   Weekly Maintenance

The centrifuge is cleaned with a freshly prepared 10% bleach solution.  Dried and caked blood spills in difficult to reach areas should be targeted.  Weekly cleaning is recorded on the weekly maintenance chart in the laboratory. 

The centrifuge buckets and inserts are inspected and cleaned as necessary by soaking for 30 minutes with a freshly prepared 10% bleach solution.  Rinse the buckets and inserts with tap water and drain on paper towels before returning to the centrifuge.

The rubber gasket affixed to the centrifuge lid prevents aerosols from leaking into the work environment.  Inspect the gasket for obvious deterioration during weekly cleaning.  To avoid prolonged contact with the bleach solution and minimize deterioration of the rubber material, wipe the gasket with a paper towel dampened with water after cleaning.

3.  Yearly Maintenance

The operating speeds of centrifuges are checked at least annually as needed for the intended use, and this is done in a safe manner. 

For centrifuges having a safety mechanism preventing the opening of the lid while in operation, the checks of rpm should be performed only by an authorized service representative of the manufacturer or an appropriately trained clinical engineer.

Records of scheduled preventive maintenance visits are stored in each section.   

Centrifuge Maintenance Log Template

Microwave Ovens 

  • Place a sign on the microwave oven that states "NO FOOD, FOR CLINICAL LAB USE ONLY."
  • To prevent burns, use protective thermal gloves when removing items that are irradiated to high temperatures in the microwave.
  • All containers used in microwave devices should be made from microwave-transparent material. Examples of microwave-transparent materials include ceramics, sodium borosilicate glass, unleaded quartz, fluoropolymers, and nonpolar plastics such as polypropylene, polyethylene, and PTFE compounds.
  • Periodically inspect the device to verify that it is maintained in a sanitary condition, contains no corrosion, and door seals are intact.
  • Microwave devices must not be used if door seals are not intact. Discard and replace immediately if there is any evidence of a broken seal.
  • If precise temperature control is required for a specific histopathology procedure, as determined by the Clinical Chief, the lab should use large-capacity microwave devices with advanced functions. These microwave devices are periodically monitored for temperature reproducibility, either through commercial temperature measurement devices or temperature sensitive strips, which allows the user to determine if the chamber has reached full temperature.
  • Do not place toxic chemicals or infectious agents in a microwave without approval of the Department of Occupational Health and Safety (DOHS). If DOHS approves these procedures, they will determine if exhaust fume control is required for a specific histopathology procedure. If this is required, the lab should use large-capacity microwave devices with advanced functions, and follow exhaust recommendations by DOHS. These units must be properly ventilated. Microwave devices should be placed in an appropriate ventilation hood to contain airborne chemical contaminants and potentially infectious agents. Microwave devices used outside a fume hood should have an integral fume extractor that is certified by the manufacturer for use in a clinical laboratory. This checklist question does not apply if only non-hazardous reagents are used in the device (e.g., water, certain biological stains).


Quantitative Pipettes

  • Pipettes used for quantitative dispensing (eg, adjustable volume, micropipettes, dilutors, and analytic instruments with integral automatic pipettors) are checked for accuracy and reproducibility initially and according to the manufacturer's recommended interval, or at least annually if not specified, and the results are recorded.

  • The initial calibration may be performed by the manufacturer or other outside facility, but in such cases the laboratory must have a record from the manufacturer or other facility that includes the technique used to check calibration, the method of shipment to prevent damage in transit, and the bias and precision of the pipette(s). The bias and imprecision must meet the specification established by the laboratory.

  • Currently, the laboratory has no procedures that pipette systems that can result in carryover. However, if any section establishes a pipette technique that results in carryover, the validation must include evaluating whether carryover effects are present. This requirement applies to both stand-alone pipette systems and to sample pipettes integrated with analytic instruments.

Analytic Balances 

  • Analytical balances are mounted such that vibrations do not interfere with readings.

  • Analytical balances must be cleaned, serviced and checked at least annually by qualified service personnel.  LP has contracted with a biomedical service provider to perform analytic balance maintenance at least annually. The vendor must use standard weights of the appropriate ANSI/ASTM Class for verifying accuracy of analytical balances at defined intervals, with records retained. Vendor must ensure calibration weights for analytical balances are well-maintained (clean, in a covered container, free of corrosion) and appropriate lifting or handling devices are available.
Last updated by Lumelski, Victoria (NIH/NCI) [E] on Dec 29, 2023