In 2013, Black Diamond’s Quality Control Lab published an investigation into a mysterious climbing harness failure, exposing a silent, lethal hazard: chemical contamination.
A climber top-roping at a gym heard a sudden “pop” while being lowered. The harness waistbelt had completely ripped apart. Fortunately, the climber grabbed the rope and escaped injury. The incident was baffling because the harness was kept in “pristine condition” inside a gym bag, never used outdoors, and showed no visible wear.
When Black Diamond analyzed the gear, the findings were alarming. A mysterious chemical had almost entirely dissolved the load-bearing nylon stitching. Alarmingly, the polyester webbing looked flawless to the naked eye. Only a meticulous structural inspection would have revealed that the harness was a ticking time bomb.
While the exact culprit was never definitively identified, the evidence pointed to acid. To understand the failure, researchers exposed test harnesses to common household and industrial chemicals. The results were sobering. After 72 hours of exposure, several everyday substances catastrophically degraded the nylon bar tacks, allowing researchers to pull the stitching apart by hand:
- Muriatic Acid: 97% strength reduction
- Sulfuric Acid (Aquarium Cleaner): 92% strength reduction
- Chlorine Bleach: 73% reduction
Even mild household items had an immediate impact. Just 30 minutes of exposure reduced nylon strength by 13% with vinegar and 9% with Woolite.
Kolin Powick, Black Diamond’s Director of Quality, noted this was the second unexplained acid-contamination incident he had investigated. The scariest takeaway? In both cases, the users had absolutely no idea how their gear came into contact with the chemicals.
While battery acid or industrial solvents seem easy to avoid, other culprits are dangerously common. Bleach-based cleaners are routinely used on gym floors, and muriatic acid is sometimes used to clean climbing holds. A harness or rope casually tossed onto a freshly washed floor—or stored in a trunk next to household cleaners—can easily absorb a invisible, lethal dose.
This incident serves as a critical reminder for the climbing community. Nylon and polyester gear must always be stored securely away from corrosive substances. Because chemical damage rarely leaves a visual scar, proper storage isn’t just maintenance—it’s a matter of life and death.