Home Podcasts THMG147 – Hydrofluoric Acid Series, Part I: Introductions

THMG147 – Hydrofluoric Acid Series, Part I: Introductions


This is the first episode in a two-part series on hydrofluoric acid. In this episode, we explore this chemical a bit and set up for the rest of the series.

Thank to our sponsors – CBRNE Convergence World 2018, FLIR, and First Line Technology.

Our hazardous materials training manual, National Emergency Response Hazmat Drills: 50 Drills for Use with Hazardous Materials Personnel, is finally available on Amazon!

Complete Show Notes

4:50 What is Hydrofluoric Acid Used For?

  • Hydrofluoric is rarely used in residential settings due to its absolute toxicity – this distinguishes it from many other acids
  • Used to dissolve sedimentary rocks – geologists use it to get to small fossils
  • It’s also used as a precursor for making other things – i.e. separating uranium isotopes
  • Used in the pharmaceutical industry and in the creation of refrigerants (fluorinated halocarbons)
  • Also used to create the electronics that go into circuit boards, wire filaments, semiconductors, and metal parts
  • You’ll also find it in cleaners, rust removers, herbicides, glass etchers, etc.
  • Know you area, and don’t just assume that a particular industry doesn’t use hydrofluoric acid
  • EPA regulations stipulate that if an industry has more than 1,000 gallons of hydrofluoric acid that are 50% or greater in concentration, they must submit a risk management plan – close to 300 facilities across the nation have submitted those plans
  • However, you’ll get a better idea of how hydrofluoric acid is being used in your area by looking at your Tier II reporting system

12:05 Hydrofluoric Acid as a Gas

  • Like many gasses, hydrofluoric acid is transported and used in a high-pressure cylinder
  • This means we can identify it via the valve number, which is 660
  • Tank sizes vary – includes 10” x 48”, 23” x 66”, and even smaller ones in the 9” x 19” range
  • Tanks will always be steel
  • Hydrofluoric acid has a molecular weight of 20 and an ILDH (immediately dangerous to life and health) level of 30 ppm – it wants to rise and will do so quickly, so always have your meter ready to help dictate your actions
  • The boiling point is 67 degrees Fahrenheit, and the vapor pressure is 788 mmHg – this means we’re right on the cusp of this product being a boiling liquid at room temperature
  • In colder temperatures (or anything less than 67 degrees), hydrofluoric acid can be found as a liquid with a very high vapor pressure

19:55 Hydrofluoric Acid as a Liquid

  • We shouldn’t even use the word “liquid” – we really mean aqueous, which is the form a substance takes when its mixed in with water
  • When hydrofluoric is mixed into water in varying degrees, we call the end product hydrofluoric acid
  • The more hydrogens and fluorines disassociate from one another, the stronger the acid is – this is interesting because it’s actually considered a weak acid
  • However, hydrofluoric acid is incompatible with over 35 specific chemicals and is known to cause violent exothermic reactions – also corrosive to many materials and is known to blow up glass containers

25:30 Managing Exposure to Hydrofluoric Acid

  • Hydrofluoric acid will burn you like any other acid – however, it can cause a numbing sensation when exposed for a short period of time – this means people delay decontamination and medical treatment because they don’t realize how badly they’ve been exposed
  • It goes deep into our tissue because the F ion is highly lipophilic (this means it plays nice with lipids or fats)
  • As it gets into our tissue, it’s brought into the cell and starts to mix with the calcium and magnesium in our cells
  • This is problematic because our central nervous system needs calcium to communicate with the rest of our body – plus, our heart beats as a result of calcium channels
  • Drop in calcium and magnesium serum is called hypocalcemia and hypomagnesemia – this is the driving force behind the extreme pain and cramping associated with exposure to high levels of hydrofluoric acid
  • At 3% solution, it can take an hour to an overnight period before the patient is aware they’ve been exposed – and that’s just from the burn
  • There have been cases where 1% of the body exposed to 50% concentration was enough to produce hypocalcemia
  • Exposure of 5% of the body to any concentration of hydrofluoric acid is enough to lower your calcium blood serum
  • 2.5% body surface contamination can be lethal within 2-3 hours – this is the minimum necessary for lower concentrations
  • Have calcium gluconate on hand to treat exposures before it drops vital levels – be aware that it’s not a fail-safe, though

31:10 Real-Life Examples of Hydrofluoric Acid Exposure

  • A 37-year old male lab technician knocked a small quantity (100-230 ml) of hydrofluoric acid onto his lap
  • His condition deteriorated despite subcutaneous injections of calcium gluconate and administration of intravenous calcium and magnesium
  • His right leg was amputated 7 days after the incident, and he subsequently died from multi-organ failure 15 days after the incident
  • In another incident, hydrofluoric acid entered a worker’s gloves – eventually, her finger was amputated due to significant bone damage

33:40 PPE Selection for Hydrofluoric Acid Spills

  • Level A should be your starting point due to hydrofluoric acid’s low IDLH, acidity, and ability to absorb through the skin
  • Always use your meters and do a scene size-up to determine what’s best, though
  • Cross-check every single piece of your PPE to make sure it’s compatible – even a small imperfection can result in death
  • Go for decontamination systems that don’t involve water – this ensures the substance doesn’t spray everywhere

Have a question? Send an email to feedback@thehazmatguys.com or leave a message on our Haz Mat Guys comment hotline: 843-628-1484

Show Sponsors
Related Episodes

The Hazmat Guys

Author: The Hazmat Guys

Warning: A non-numeric value encountered in /home/thehazmatguys/public_html/wp-content/themes/Newsmag/includes/wp_booster/td_block.php on line 997


Please enter your comment!
Please enter your name here

This site uses Akismet to reduce spam. Learn how your comment data is processed.