It’s sometimes assumed that coefficient of friction (COF) has a maximum theoretical and practical  value of 1.00. This isn’t true; there is no maximum. It is true that values exceeding 1.00 are so slip-resistant that their actual value is often of little interest.

Some COF measuring instruments, such as BOT-3000E and English XL, are not capable of measuring values above 1.00. However, the pendulum, Tortus, and even the obsolete ASTM C 1028-07 can measure levels above 1.00. A smooth dry floor and a soft rubber slider (simulating athletic shoe bottoms or bare feet) may give dynamic or static COF exceeding 1.0, 2.0 or even 3.00.

Stumbling may occur when going from a low COF floor such as polished marble to an unexpectedly high COF surface such as plush carpet. However, this does not mean that high-COF floors are not safe. One can even walk barefoot on a bed of nails — but be careful, please!