Soft contact lenses are incompatible with which operations?

• A. CBRN respirators
• B. Diving operations
• C. Night missions
• D. High altitude flights

Answer: (A)

In hazardous environments where you must wear a CBRN respirator, eye protection must provide a complete seal with the facepiece. Soft contact lenses don’t offer a protective barrier against chemical or biological agents, and they can trap contaminants between the lens and the cornea. If exposure occurs, decontamination and eye irrigation become more complicated, and removing lenses under those conditions is risky. The protective system relies on goggles or a built-in facepiece with a sealed seal around the eyes; wearing lenses can interfere with that seal and with rapid, safe decontamination. So soft contact lenses are incompatible with operations that require CBRN respirators.

Diving operations, night missions, and high altitude flights don’t carry the same universal incompatibility: lenses can be worn in many of these contexts, though each scenario has its own eye-protection considerations and potential risks (for example, divers use masks that protect the eyes, and dry cabin air at high altitude can irritate eyes). The key idea is that CBRN protection demands effective eye sealing and robust protection, which soft contact lenses cannot provide.