Is there a safe way to induce hypercapnia in a controlled training environment? It's a weird feeling. If divers knew what to expect then they wouldn't be surprised and would be less likely to panic.Off topic, but we need to stop perpetuating the myth that panic attacks have something to do with someone's experience/mental "toughness"/etc. Especially in diving, physiological response to eleveated CO2 levels is usually the culprit.
I have been on the edge of panic myself once due to (I think) CO2 loading from working too hard and over breathing my regulator (and yes, I was using a high-quality, properly maintained regulator with a low-density gas mix). Tech diving courses do cover the risks of CO2 but it's hard to appreciate without experiencing it yourself.