Tape measure
7
3MEASURE HEAD CIRCUMFERENCE
Use a tape measure to determine the maximum head
circumference (to the nearest 1/16 inch) above the ears. Ensure
that the caliper touches the skin lightly and does not indent the
skin. Record the measurement.
4SELECT HELMET SIZE
Referring to the tables below (for inches or millimeters), select
the helmet size based on head length, head breadth, and head
circumference.
INCHES:
Helmet Size Head Length (in.)
Head Breadth
(in.) Head Circumference (in.)
Small (S) Up to 7¼ Up to 6½ Up to 21¼
Medium (M) 7¼ to 7¾ 6½ 21¼ to 22½
Large (L) 7¾ to 8¼ 6½ 22½ to 23½
Extra Large (XL) 8¼ and greater 6½ and greater 23½ and greater
MILLIMETERS:
Helmet Size Head Length (mm)
Head Breadth
(mm) Head Circumference (mm)
Small (S) Up to 184 Up to 165 Up to 539
Medium (M) 184 to 196 165 539 to 571
Large (L) 196 to 209 165 571 to 596
Extra Large (XL) 209 and greater 165 and greater 596 and greater
NOTE: For best sizing, wear the helmet with all forms of equipment that will be used during an operation.
Include length of hair, balaclava, cold-weather gear, protective mask, and communication equipment. If unable
to obtain size with actual helmets, select largest size helmet based on any of the three measurements obtained
using a caliper and/or tape measure.
