This tool helps quantify tobacco exposure for clinical assessment by calculating cumulative exposure based on intensity and duration.
Total Pack-Years:
10
A pack-year is equivalent to smoking one pack of 20 cigarettes per day for one year.
Pack-years are a clinical measure used to quantify a person's lifetime exposure to tobacco. This calculation helps healthcare providers assess the risk of developing smoking-related diseases, such as lung cancer or COPD.
Pack-Years = (Cigarettes per Day / 20) × Years Smoked
Imagine an individual who has smoked an average of 30 cigarettes per day for a total of 15 years.
A history of 20 or more pack-years is a common threshold for determining eligibility for annual lung cancer screenings. It indicates a level of exposure where clinical monitoring becomes significantly more relevant for early detection.
This specific formula is the medical standard for commercial cigarettes. Because nicotine concentrations and delivery methods vary for pipes, cigars, and vaping devices, they are typically evaluated using different clinical criteria.
You should only sum the actual years during which you were an active smoker. If you quit for a period of 5 years in the middle of your smoking history, those 5 years should be subtracted from your total duration.
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