The following is presented as a public service. It is copied directly out of a handbook from Performance Textiles, Inc. which I obtained at the 1999 PIA Symposium in San Diego.
This information is intended as helpful suggestions. Performance Textiles makes no guarantees of results and assumes no obligation or liability whatsoever in connection with this information. For that matter, neither do I, but with all of the questions asked about cleaning parachutes, I wanted to get the best information available out to the public.
Most stains can be avoided by immediately wiping the stained area with an absorbent cloth or paper towel. Always handle the fabric carefully and treat the smallest area possible. The following cleaning procedures have been used successfully to remove stains from coated and non-coated parachute fabrics:
Stain Type: Food, soda, catsup (kethup for most of us), mud, dirt, sweat.
Procedure: Use clean water and a sponge gently. Rinse area thoroughly with clean water. NEVER USE FULL STRENGTH DETERGENT.
Stain Type: Mustard, red clay, blood.
Procedure: Use a MILD detergetn. Let it sit on the stain 3-5 minutes, then sponge gently and then firmer if needed. DON'T use bleach as it can (my comment as a chemist...WILL) affect the fabric strength, finish, and color. (My comment....Can you say turn it into tissue paper quality?!!!)
Stain Type: Motor oil, hydraulic fluid, grease, exhaust and demo smoke.
Procedure: Allow to sit on stained area for 1 minute and work into the stain with a sponge. Then gently and carefully clean and rinse as above. Be aware that staining chemicals and cleaning agents can affect fabric strength, finish, and color. (In this paragraph, they left out the comment about what to use. Presume they mean mild detergent again.)
DO NOT USE FLAMMABLE SOLVENTS SUCH AS GASOLINE, ACETONE, MINERAL SPIRITS, PAINT THINNER, ETC., as they may damage the fabric or fabric coating and other components.
WARNING: If the fabric shows any sign of (excessive) wear, fraying, or a cut, scratch, or tear, do not use the parachute. (My comments: I added the word excessive. Gee whiz...if we followed this protocol, we'd have very few jumps on our parachutes because they all have some minor stuff as they age. That's one reason why a rigger should check the systems out routinely!)
Never use bleach or products containing bleach. Contact the original parachute manufacturer for any problems associated with the parachute.
One final sentence from the pamphlet: Cleaning may be more harmful than the spot!
Stay safe out there.
Blue Skies & Safe Dives from Mike Turoff,
Co-author (with Dan Poynter) of Parachuting, The Skydivers Handbook, 7th ed.
Instructor and Tandem Examiner, Jump Pilot
Subject: Spot Cleaning of Nylon Parachute Fabric