Gloves That Survive pH 12: PPE for Gel and Dust Work

The burn was under a wristwatch. The operator had been wearing gloves all shift, gauntlets that came halfway up the forearm, and a splash had run down the inside of the cuff and sat against the skin under the watch strap for the rest of the afternoon. He noticed it at the end of the shift when he took the watch off. By then it was a 40 millimetre patch of reddened, blistered skin that took three weeks to settle.

Gelled leachate is not obviously dangerous. It is thick, it does not splash much, and it looks like mud. But it sits at pH 11 to 12.5 in most formulations, and a caustic material that stays in contact with skin for six hours will do damage that a splash never would.

Two Hazards, Not One

The dust and the gel are different problems and they need different answers.

Dust is an inhalation and eye hazard. The powder is fine, it is alkaline, and it is extremely hygroscopic — a particle that lands on a moist eye or a sweaty forearm will draw water and become a caustic droplet within seconds. It is also slippery when wet, which is a slip hazard on any hard floor.

The gel is a contact hazard. It does not hurt immediately, which is exactly the problem: a caustic burn develops over hours and the wearer has no warning signal until the skin is already damaged.

Gloves: Which Ones and for How Long

Nitrile is the default and it is adequate for gel contact, but thin nitrile degrades and the failure is invisible — no hole, no tear, just a thinning that lets caustic through slowly. Two hours is a working limit, not a manufacturer’s guarantee, and in warm weather it is shorter.

The cuff is the part that matters most. A gauntlet that ends at the wrist collects material. A gauntlet that reaches mid-forearm, worn with the cuff outside the sleeve and taped or elasticated, does not. That single detail prevents more burns than any glove specification.

The Counter-Intuitive Finding

A site that introduced full face shields and heavy gauntlets for all gel work saw hand injuries go up over the following quarter. The crew were taking the gloves off to judge the gel by feel — the gauntlets were too thick to feel consistency through, so they removed them for the one task they did twenty times a shift.

The fix was not discipline. It was a thinner glove for sampling and a thicker one for washdown, with the thick pair kept on a hook by the hose rather than worn all day. PPE that makes the job harder gets circumvented, and the circumvention happens at the moment of highest exposure.

Eyes, Lungs, Skin

Goggles, not safety glasses. Glasses leave a gap at the top and the bottom, and dust finds gaps. Where there is a splash risk, a face shield over goggles.

For dust, a half-mask with a P2 or P3 filter at the hopper, fit tested, and clean shaven at the seal. For the mixing area, a mask is not the control — extraction is. If you need a mask to stand next to the mixer, the extraction is not working.

For skin, cover it. Long sleeves, no shorts even in August, collar closed, and no exposed skin between glove and sleeve. Barrier cream is a supplement for the face and neck, not a substitute for gloves, and it does not survive a full shift.

The Washing Point

A plumbed eye wash and a safety shower within ten seconds’ walk of the mixing point, tested weekly and logged. A bottle of eyewash in a first aid box 80 metres away is not a washing facility.

Add a hand-wash station with running water and a pH check: a strip on the skin after washing tells you whether you got it all off. Cheap, and it catches the case where someone has been working with a pinhole in a glove for two hours and does not know.

What Good Looks Like at the End of a Shift

No gel on cuffs. No dust on the shoulders. Gloves off before the door, not in the cab. Boots washed, because dried gel on a boot sole is a slip hazard on a steel plate. And a supervisor who notices when someone has stopped wearing the goggles.

The handling and safety section of the operating guide covers the caustic and dust controls together, which is useful when writing a site-specific procedure that has to satisfy both the safety officer and the operations manager.

One number to leave with the crew: at pH 12, skin contact damage begins in minutes, not seconds, and the sensation arrives later than the injury. That is why the rule is coverage rather than caution.