biohazard sign
Toxic warning marker
A biohazard sign displays the distinctive three-ringed symbol warning of biological hazards—infectious agents, contaminated materials, or other dangers to living organisms.
The symbol appears on laboratory doors, medical waste containers, and specimen bags: The biohazard sign on the freezer meant only trained personnel could access it.
The iconic trefoil design, created in 1966, was chosen specifically because it had no prior meaning and couldn't be confused with other symbols.
- hazmatToxic materials needing precautions
- hazmat suitSealed garment blocking toxins
- toxicCapable of causing harm
- toxic wasteDangerous industrial refuse
- warningAlert about danger
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- safety alertswarning light, fire alarm, smoke alarm, smoke detector, emergency alert
- Lab Safetysafety goggles, lab safety, lab coat, PPE, fume hood
biohazard signradiation warning
Signal of ionizing danger
radioactive symbol · skull and crossbones · high voltage sign · poison symbol · flammable sign
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