Laboratory Operations
Quality management
Quality control is run at defined intervals with at least two levels and evaluated on Levey-Jennings charts using Westgard rules. Proficiency testing is mandated under CLIA '88 and must be handled as unknown specimens by routine staff; failure triggers corrective action. Method validation covers accuracy, precision, analytical sensitivity, linearity, interference, and reference interval verification.
Safety
OSHA Bloodborne Pathogens Standard requires an exposure control plan, hepatitis B vaccination offer, PPE, and engineering controls. Standard precautions treat all blood and body fluids as infectious. Chemical hygiene plans, SDS access, and hazard labeling are required for chemical hazards; fire extinguishers are classed A (ordinary combustibles), B (flammable liquids), C (electrical), and D (metals).
Specimen handling
Order of draw: blood cultures, sodium citrate (light blue), serum (red or gold), heparin (green), EDTA (lavender), oxalate/fluoride (gray). Additive carryover from EDTA falsely raises potassium and lowers calcium; draw a discard tube when using butterfly sets for coagulation.
Traps
- A 1-2s rule is a warning only; 1-3s and 2-2s require rejection and investigation.
- Delta checks catch specimen mix-ups and mislabeled tubes.
- Competency assessment must be documented at defined intervals for all testing personnel.
- Critical values require documented read-back and notification.
Statistics and rule of thumb
CV % = (SD / mean) x 100. A result outside the reference interval is not automatically abnormal; interpret it against the patient's prior results and clinical context before calling the provider.