Which of the following is a normal adult respiratory rate range?

• A. 8-12/min
• B. 20-30/min
• C. 12-20/min
• D. 25-35/min

Answer: (C)

The main concept here is understanding what a normal resting respiratory rate looks like in an adult. In healthy adults, the typical resting rate is about 12 to 20 breaths per minute. This range reflects normal ventilation without signs of distress or excessive work of breathing. A rate of 8–12 breaths per minute is lower than normal and can indicate bradypnea, which isn’t considered the standard resting rate. Rates of 20–30 and 25–35 breaths per minute are higher than normal at rest and point to tachypnea, which can occur with fever, anxiety, pain, hypoxia, or respiratory illness. When clinicians measure respiratory rate, they usually count for a full minute in a quiet patient to get an accurate reading as part of routine vital signs.