http://jckronbauer.blogspot.com/2014/12/some-say-the-stig-heartbeat-is-measured-in-rpm-his-oxygen-quantity-is-measured-in-air-fuel-mixture-instead-of-sp02-he-has-oil-in-his-veins-instead-of-blood-and-the-pressure-is-measured-in-lbf-pol2.html