What type of burn is NOT associated with liquid ammonia exposure?

The correct answer is determined by understanding the effects of liquid ammonia exposure. Liquid ammonia primarily causes chemical burns due to its highly alkaline nature and potential to damage tissue upon contact. It can also cause thermal burns, as it can lead to significant cold injury when it evaporates rapidly and draws heat from the skin, creating a frostbite-like effect.

Friction burns occur due to the abrasive contact of one surface against another, which does not relate to the exposure of ammonia. Additionally, while ammonia can irritate the respiratory system when inhaled, causing respiratory distress, this is categorized separately from the effect of direct exposure to the skin.

Given this context, a friction burn is not associated with liquid ammonia exposure, since this type of burn results from mechanical abrasion rather than a chemical agent or contact with liquid. Hence, it is clear why the other types of burns can be related to ammonia exposure, while friction burns cannot.