I have a machining department that uses an aqua regia soak as part of the manufacturing process. There is no direct contact with the aqua regia. Parts are put in and removed from the soak using tongs.

I am assisting in updating our SOP for this procedure. I am writing/rewriting the safety portion of the SOP.

I was hoping to find some simple best practices for care and replacement of PPE.

We use goggles, face shields, rubber aprons, gloves, and nitrile gloves/gauntlets.

The regular gloves are being used as a glove liner and are disposed of after each use. I am including language about leak checking these liners prior to use.

The long gloves will be inspected prior to use, initialed and dated at first use and discarded every 6 months. If a glove is found to have visible holes or cracks during inspection or is directly exposed to aqua regia, it will be removed from service early. Additionally, gloves will be washed after each use.

We will track glove/gauntlet replacement using a compliance calendar.

What is a conservative replacement schedule for goggles, face shields, and rubber aprons? I will include instructions for pre-use inspection and post use washing. Obviously, if a piece of PPE doesn't pass inspection or is exposed to acid, it will be replaced.

Is there anything else I am missing?

I like to keep guidelines to be very clear for all workers but particularly when those workers don't normally work with these types of chemicals.

I appreciate any input and advice.

Regards,

Juli Bencivengo

Lab Manager

Momentive Performance Materials