Plan on working with HF? A friend who was president of an HF manufacturing company once gave me some valuable advice. He said there are several things to do before the plastic bottle of HF arrives. First, have a well ventilated fume hood available. Next, read up on HF first aid. Try to identify a hospital ER that could cope with an HF incident. How do you do that? You call and ask questions. Get some calcium gluconate salve.  Learn what to do with it.  If you have an incident, you will need to get decontaminated before you arrive at the hospital, otherwise there may be delays in getting teatment  by the medical staff.

Here is my personal policy. You follow your own policies. If you handle HF and do not have a specific response plan, get one in place. If you handle this acid, you need to have a plan.

Do not rely on the local fire department to know what to do.  They’ll want to take charge as soon as they arrive. Time will be lost as they ignore the staff of chemical experts standing right there while they confer on a plan. I’ve seen variants of this many times. It might transpire that the firemen will be ordered to stand clear of you until their commander has a plan for dealing with the contamination. So there you’ll sit.

Your main concern in a major splash incident is to get decontaminated.  Your lab buddies who are there with you need to know how help you with this so there is no delay in getting you decontaminated. Do not wait for the fire department to come decontaminate you. Strip off contaminated clothing and get under the shower pronto, even if you have to use your one good arm to drag yourself there.

HF is a weak acid with a pKa of 3.17.  It is somewhat skin permeable and will cause deep tissue injury.  In addition to the general hydrolytic havoc associated with an acid exposure, HF delivers fluoride which scavenges calcium and will precipitate calcium fluoride in your tissues. That is what sets an HF exposure apart. This link to Honeywell Specialty Materials is especially well written and informative.

Avoid inhalation exposure and provide for splash protection.  If you are heating it, consider using a full face respirator with appropriate cartridges when opening the sash of the hood when  handling the reaction mixture.  Wear a long rubber or plastic gloves and apron and make sure that your lab coat is non-absorbant. Be fastidious.

Don’t be afraid of HF. It is a lot like a table saw. You just have to know how to behave around it. And like a table saw, it’ll take body parts or worse from the careless or the complacent. You have to handle it carefully every single time. Be in the moment. Don’t get distracted by talkative bystanders. Pay attention to what you’re doing.

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