A nurse is caring for a client receiving oxygen therapy. Which safety measure is most important in the client's room?

OXYGEN SAFETY — FIRE PREVENTION: Oxygen does not burn itself but VIGOROUSLY SUPPORTS COMBUSTION — fires burn hotter and faster in an oxygen-enriched environment. SAFETY MEASURES: NO SMOKING (post 'Oxygen in Use — No Smoking' signs); no open flames, candles, matches, lighters; avoid electrical equipment that could spark; no petroleum-based products (petroleum jelly, oil) near oxygen — use water-based lubricants; avoid wool/synthetic fabrics that generate static; ensure proper grounding of electrical equipment; keep oxygen sources away from heat; SECURE oxygen cylinders (can become projectiles if the valve breaks); HOME OXYGEN: Educate about the same precautions; keep oxygen away from stoves, heaters, and gas appliances; ADDITIONAL: Monitor for oxygen toxicity with high concentrations over time; for COPD patients, titrate carefully (target SpO2 88-92%); LPN role: ensure a safe oxygen environment, post warnings, educate the client and visitors, remove ignition sources.