- Make up a solution of 7oz borax and 3oz of Boric acid in gallon of hot water.
- Soak the costume for two minutes and ring out. Line dry.
- Repeat every time the costume is washed.
Alternatively commercial fire retardants are available online or from shops like the-stitchery.
the-stitchery currently stocks “FireCheck” 750 ml spray (http://www.mslfirecheck.com) for the price of £13.99* (no discount) which can be bought online for £18.90. the-stitchery also offers an all-year 10% discount on costume supplies!*