Pulse oximeters may be inaccurate on people of color, FDA warns By Kate Gibson Doctor argues why pulse oximeters are needed Pulse oximeters — viewed as a critical in the fight against COVID-19 — may not work as advertised for people of color. "The devices may be less accurate in people with dark skin pigmentation," the U.S. Food and Drug Administration stated in a safety notice posted on Friday. The FDA's warning offers a toned-down version of recent and even years-ago research finding racial disparities in the performance of pulse oximeters, which measure oxygen levels. The clamp-style devices attach to a person's finger and track the amount of oxygen in their blood. Low oxygen levels signal a COVID-19 patient might be getting worse.