Body Surface Area

'Calculate an Estimate of your Body Surface Area' 

Knowledge of the human body surface area (BSA) has important applications in medical practice, in particular for the correct dosage of drugs, for cardiac index to determine heart performance, as well as design of clothes.  Accurate calculations of body surface area are essential for the correct dosage calculations in the treatment of chemotherapy.  A recent study found that 3% of dosages of a chemotherapy drug contained an error because of inaccurate measurements of body surface area.  These incorrect dosages included a small amount of patients given potentially lethal overdoses.

Working in small groups you are going to estimate the surface area of one of the people in your group.  Then you can check your result against one of the formula used in medicine to estimate BSA.


For students requiring a structured worksheet use  BSA calculation

There are also some  BSA teacher notes


Here follows an outline of what the task is. 

  • Estimate the surface area of the body of your teacher. Which of the following would give the closest estimate 0.1m², 0.5m², 1m², 2m², 5m², 20m², 100m² ?
  • Working in small groups make the necessary measurements to calculate the surface area of a member of your group.
  • Find the total surface area, then check the calculations accuracy by comparing the value found using this formula
    «math xmlns=¨¨»«mi»B«/mi»«mi»S«/mi»«mi»A«/mi»«mo»§#8776;«/mo»«msqrt»«mfrac»«mrow»«mi»m«/mi»«mo»§#215;«/mo»«mi»h«/mi»«/mrow»«mn»35«/mn»«/mfrac»«/msqrt»«/math» 
    where BSA is in square metres, m is the body mass in kilograms,h is the body height in metres.
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