A nurse is preparing to give insulin for the first time on a new unit. What safety check is critical BEFORE administering any insulin?

INSULIN DOUBLE-CHECK is a safety standard in most facilities because insulin errors are common and dangerous. What to verify: TYPE — insulin types look similar but have vastly different durations and onset times; NPH and Regular insulin are often confused; Lantus (glargine) is a 24-hour insulin that looks like regular but gives fatal hypoglycemia if given when Regular was intended; DOSE — insulin is measured in UNITS, not mL; conversion errors happen; TIMING — Regular insulin 30-60 minutes before meals; lispro/aspart immediately before meals; Lantus once daily at bedtime; BLOOD GLUCOSE — check before administering and hold if below the parameter (typically hold if glucose below 70 mg/dL); TWO-NURSE VERIFICATION — per facility policy, most high-alert insulin doses require two licensed nurses to independently verify before administration.