Written and maintained by CASRAI Editorial Board
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This page describes products and general use; it is not medical advice.
Cast tape (also called casting tape or fiberglass casting tape) is a roll of knitted fibreglass fabric coated with a water-activated polyurethane resin. It hardens into a rigid, lightweight shell when it is wetted, and is used to build orthopaedic casts, splints, and orthotic or prosthetic devices. Clinic staff, buyers and students use this page to understand what the product is, how one manufacturer says it sets, and how it is handled and stored. All handling figures below come from one manufacturer’s instructions for use (IFU), checked 2026-10-30, and may differ for other products.
What cast tape is
Cast tape is a synthetic alternative to plaster bandage. The KRUUSE fibreglass casting tape IFU describes the tape as designed for the most common orthopaedic casts as well as prosthetics and orthotic devices, and says specific applications are the responsibility of on-site qualified medical professionals. Who uses it: orthopaedic and emergency clinics, casting rooms, and veterinary practices that apply casts; stock managers and buyers who order and store it.
How it is built and how it hardens
The IFU describes a specially knitted fibreglass fabric impregnated with water-activated polyurethane resin. Exposure to moisture or water starts a chemical reaction that hardens the material. Finished casts are described as lightweight, durable, strong, porous and radiolucent (X-rays pass through them).
Because humidity alone can start the reaction, each roll is sealed in a vacuum-sealed or dried-air foil pouch, and the IFU says to open only one roll at a time.
Cast tape versus plaster bandage
Both products harden when wet. For a side-by-side table, see plaster bandage. One difference the IFU states directly: dust from cutting a fibreglass cast is less than that from plaster of Paris casts, though it should still not be breathed in.
Types and variants
| Type | Typical use | Key difference (source) |
|---|---|---|
| Fibreglass casting tape (polyurethane resin) | Casts, orthotic and prosthetic devices | Water-activated resin on knitted fibreglass; radiolucent and porous when finished (KRUUSE IFU) |
| Synthetic resin casting tape, 10 cm x 3.6 m | One patient, one procedure | Listed in the MSF Unicat catalogue as single-use, under EMDN code M03050202 “Synthetic cast bandages and splints” (MSF Unicat, checked 2026-10-30) |
Casting tape is used over underlayers such as stockinette and cast padding, which the IFU lists as the first layers.
Sizes and specifications that matter
| Item | Value | Source |
|---|---|---|
| Example roll size | 10 cm wide x 3.6 m long | MSF Unicat product 18469 |
| Storage temperature | 15-30 C (59-86 F) | KRUUSE IFU |
| Flammability | Meets class I requirements of 16 CFR 1610 (CS191-53) | KRUUSE IFU, for that product |
What the IFU says about setting times
These figures are the manufacturer’s, for its own product, and depend on water temperature and technique.
| Condition | What the IFU states |
|---|---|
| Water temperature stated for the roll | Room temperature, 20-25 C (68-77 F) |
| Roll squeezed while submerged | Set time about 3 minutes |
| Roll dipped and removed without squeezing | Set time about 4 minutes (longer) |
Without squeezing, the IFU adds, warmer water shortens set time and cooler water lengthens it.
Safe handling and storage basics
- Gloves. The resin adheres firmly to unprotected skin and clothing, so the IFU requires protective or surgical gloves while handling the tape.
- Heat. The IFU warns that excessive heat may cause burns and links heat build-up to excessive layers and to water above 27 C (80 F).
- Ventilation. Respiratory sensitivity may occur, so the IFU recommends using the tape in a ventilated area.
- Packaging and storage. Each roll is sealed in a pouch; the IFU says a punctured pouch makes the tape harden, and a hard pack should be disposed of rather than used. A wet pack is dried with a towel and stored dry and cool; each box and pouch carries a lot number and expiry date, and the IFU recommends rotating stock.
- Disposal. Casts may be incinerated or sent to landfill in line with local regulations.
The IFU does not recommend water immersion and suggests non-absorbent undercast material or a water-resistant cover where water exposure is expected. See shower cover for a cast for covers, and what is a splint and splint kit contents for related supplies.
FAQ
Is casting tape the same as fiberglass casting tape?
The terms are used interchangeably for the product described here, a knitted fibreglass fabric with polyurethane resin. Other synthetic resin tapes also exist, so check the product description for the material.
How long does cast tape take to set?
For the KRUUSE product, the IFU gives about 3 minutes when the roll is squeezed while submerged and about 4 minutes if it is dipped without squeezing. Other products differ.
Can a fibreglass cast get wet?
The IFU says immersion in water is not recommended and, where water exposure is expected, recommends non-absorbent undercast material or a water-resistant cover. Questions about an individual cast belong with the clinician who applied it.
Sources
- KRUUSE Fibreglass Casting Tape, instructions for use, manufacturer IFU, English section, checked 2026-10-30.
- MSF Unicat, casting tape, synthetic, resin, 10 cm x 3.6 m (product 18469), checked 2026-10-30.
