Anaes SAQs · Measurement & monitoring physics

MRI, laser and radiation safety

Primary physics — MRI four-zone model (Zone I public, Zone II screening, Zone III controlled access, Zone IV scanner room with quench button; static field projectile effect); laser hazards (retinal burn from reflected beam, plume inhalation, airway fire from CO2 laser igniting PVC ETT in oxygen-enriched atmosphere; prevention via laser-resistant ETT, saline-filled cuff, lowest FiO2, wet towels, eye protection); ALARA radiation protection (TIME minimise fluoroscopy, DISTANCE inverse square law doubling distance quarters dose, SHIELDING 0.5 mm lead-equivalence aprons, thyroid shields, leaded glass; film badge or TLD dosimetry).