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Exposure to reduced levels of breathable oxygen results in hypoxic hypoxia. In tactical aviation, hypoxia is recognized as a serious potential risk. One of the most well-documented and robust effects of hypoxia is on the visual system, which has profound implications for human performance during aviation. Specifically, hypoxia is known to impair color perception, perception of light intensity, and result in symptoms that include tunnel vision, graying, and blurry vision. However, the mechanism by which vision is impaired during hypoxia is poorly characterized. The current study sought to specifically examine S-cone sensitivity along with visual evoked potentials (VEPs) during a moderate and severe normobaric hypoxia exposure. Participants completed a modified blue cone contrast test (CCT) as well as a pattern reversal paradigm while electroencephalography (EEG) was recorded to measure visual evoked potentials. Participants completed these tasks during three separate, counterbalanced visits that only differed in the oxygen concentration they were exposed to: normoxia (21 oxygen), moderate hypoxia (11.7 oxygen), or severe hypoxia (9.7 oxygen). Results showed null effects on both CCT performance and VEP amplitude by condition. Hypoxia symptom reporting did demonstrate high intra-individual variability in subjective symptom reporting across the two altitudes used here. Future work should continue to investigate the mechanism(s) of visual impairment during acute hypoxia while taking into consideration lighting conditions and stimuli that are most relevant to the operational environment.