How to Waterproof a Leg Cast

A cast is a hard shell made of two layers that protects a broken or fractured bone. The inner layer is made of cotton and the outer layer is made of plaster or fiberglass, which is bendable plastic. Casts are not waterproof and should not be submerged in water without a protective covering. If the inner cotton gets wet, it could cause a rash or infection, which will result in a longer recovery period. Keep a leg cast protected in water with a waterproof cover.

Things You'll Need

• Waterproof cast cover
• Tape measure
• Large plastic bag
• Rubber band
• Waterproof tape
• Cling wrap

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Instructions

Waterproof with Cover and Hand Pump

• 1

  Look for a waterproof cast cover that includes a hand pump. These are available at medical supply companies, doctor offices and drug stores.

• 2

  Measure the length of the leg to purchase the correct cast cover size. Use a flexible tape measure and measure the back of the cast, from the back of the heel to the top of the cast. Add 2 inches to the measurement.

• 3

  Measure the circumference of the leg, just above the cast, and subtract 1 inch. You will subtract an inch to ensure the waterproof cover is tight against the leg to prevent any water from entering through loose areas.

• 4

  Slide the cover over the cast so it is completely covered. You should have an additional inch of material extending beyond the top of the cast.

• 5

  Use the hand pump, included with the waterproof cast cover, to remove all the interior air. Once the air is removed, the cover should look tight and wrinkled against the cast.

• 6

  Wait up to 10 minutes before entering the water to ensure the waterproof cover will remain tight and wrinkled.

Waterproof with Plastic Bag

• 7

  Slip the bag over the leg cast and pull up to just beyond the top of the cast. Use your hands to pat down the bag to remove air on the inside before sealing.

• 8

  Stretch a large rubber band around the foot and up the leg of the cast on the exterior of the bag. Settle the rubber band just above the top of the cast, over your leg. The rubber band should be snug over the bag, but should not have a feeling of discomfort over your leg.

• 9

  Wrap waterproof tape over the rubber band. This will seal the cast into the plastic bag and prevent water from entering.

• 10

  Cut off any excess bag that extends beyond the tape.

Waterproof with a Non-Latex Seal

• 11

  Measure the foot from the heel to the top of the cast, and add 1-inch to purchase the right size.

• 12

  Slip the cast inside the bag. Adjust the bag around the foot before closing the seal.

• 13

  Pull the non-latex diaphragm seal over the top of the cast. It will extend upward on the leg to create an air-tight seal.