NXR3LF Tru-Lite lead-free Vest-Skirt Shield Apron

As for any other purpose, simply measure your total height. This gives you an estimation for your general size in case you are unaware of it.

Aprons which provide protection for the whole body are worn on the shoulders and they must be at least of knee length. (The knees are among the body parts which are susceptible to radiation.) Measure your height (length) from the middle of one shoulder to the lower end of a knee. It is important to stand straight for this process.

Measure your back at the widest part: from shoulder to shoulder. Keep your arms down and close to the sides of your body, and stand straight.

Measure your height (length) from the middle of one shoulder to about 5 cm below your hip. It gives you the length of the vest you need.

Measure your height (length) from your waist to the lower end of your knees. It gives you the length of the skirt you need.

First, measure your back at the height of the widest part of your breast(s), from one of the middle points (halfway between your front and back side) to the other.

Next, measure your breast(s) at the widest part, again, between the middle points described above.

Measure the girth of your waist horizontally. In many cases (especially for women), but not always, it is the slimmest part of your upper body if you look yourself face-to-face in a mirror.

Measure the girth of your hip horizontally, at the widest part of it.

Your armpit girth is measured vertically (when you are standing). The correct way to do so is to measure it from the top of your shoulder leading the ribbon down to your armpit and back. This is an important piece of data. If armpit size of an apron (or a vest) is too big, there will be a gap near the side of your body when you bend forward. This gap can expose the breasts to radiation, which is particularly dangerous.