Hazzards
<p >Hydrofluoric acid is a highly <a href="http://en.wikipedia.org/wiki/Corrosive" title="Corrosive" class="mw-redirect" >corrosive</a> liquid and is a contact<a href="http://en.wikipedia.org/wiki/Poison" title="Poison" >poison</a>. It should be handled with extreme care, beyond that accorded to other mineral acids. Owing to its low <a href="http://en.wikipedia.org/wiki/Dissociation_constant" title="Dissociation constant" >dissociation constant</a>, HF as a neutral lipid-soluble molecule penetrates tissue more rapidly than typical mineral acids. Because of the ability of hydrofluoric acid to penetrate tissue, poisoning can occur readily through exposure of skin or eyes, or when inhaled or swallowed. Symptoms of exposure to hydrofluoric acid may not be immediately evident. HF interferes with nerve function, meaning that burns may not initially be painful. Accidental exposures can go unnoticed, delaying treatment and increasing the extent and seriousness of the injury.<sup id="cite_ref-pmid11505130_7-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Hydrofluoric_acid#cite_note-pmid11505130-7" >[8]</a></sup></p>
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Once absorbed into blood through the skin, it reacts with blood calcium and may cause cardiac arrest. Burns with areas larger than 25 square inches (160 cm<sup >2</sup>) have the potential to cause serious systemic toxicity from interference with blood and tissue calcium levels.<sup id="cite_ref-RMTHFE_8-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Hydrofluoric_acid#cite_note-RMTHFE-8" >[9]</a></sup> In the body, hydrofluoric acid reacts with the ubiquitous biologically important <a href="http://en.wikipedia.org/wiki/Ion" title="Ion" >ions</a> <a href="http://en.wikipedia.org/wiki/Calcium" title="Calcium" >Ca<sup >2+</sup></a> and <a href="http://en.wikipedia.org/wiki/Magnesium" title="Magnesium" >Mg<sup >2+</sup></a>. Formation of insoluble <a href="http://en.wikipedia.org/wiki/Calcium_fluoride" title="Calcium fluoride" >calcium fluoride</a> is proposed as the etiology for both precipitous fall in serum calcium and the severe pain associated with tissue toxicity.<sup id="cite_ref-Goldfrank_9-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Hydrofluoric_acid#cite_note-Goldfrank-9" >[10]</a></sup> In some cases, exposures can lead to <a href="http://en.wikipedia.org/wiki/Hypocalcemia" title="Hypocalcemia" class="mw-redirect" >hypocalcemia</a>. Thus, hydrofluoric acid exposure is often treated with <a href="http://en.wikipedia.org/wiki/Calcium_gluconate" title="Calcium gluconate" >calcium gluconate</a>, a source of Ca<sup >2+</sup> that sequesters the fluoride ions. HF <a href="http://en.wikipedia.org/wiki/Chemical_burn" title="Chemical burn" >chemical burns</a> can be treated with a water wash and 2.5% calcium gluconate gel.<sup id="cite_ref-pmid2741315_10-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Hydrofluoric_acid#cite_note-pmid2741315-10" >[11]</a></sup><sup id="cite_ref-pmid17091088_11-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Hydrofluoric_acid#cite_note-pmid17091088-11" >[12]</a></sup><sup id="cite_ref-12" class="reference" ><a href="http://en.wikipedia.org/wiki/Hydrofluoric_acid#cite_note-12" >[13]</a></sup> or special rinsing solutions.<sup id="cite_ref-pmid15461243_13-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Hydrofluoric_acid#cite_note-pmid15461243-13" >[14]</a></sup><sup id="cite_ref-14" class="reference" ><a href="http://en.wikipedia.org/wiki/Hydrofluoric_acid#cite_note-14" >[15]</a></sup> However, because it is absorbed, medical treatment is necessary;<sup id="cite_ref-RMTHFE_8-1" class="reference" ><a href="http://en.wikipedia.org/wiki/Hydrofluoric_acid#cite_note-RMTHFE-8" >[9]</a></sup> rinsing off is not enough. Intra-arterial infusions of calcium chloride have also shown great effectiveness in treating burns.<sup id="cite_ref-15" class="reference" ><a href="http://en.wikipedia.org/wiki/Hydrofluoric_acid#cite_note-15" >[16]</a></sup></p>
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Hydrogen fluoride is generated upon combustion of many fluorine-containing compounds such as products containing <a href="http://en.wikipedia.org/wiki/Viton" title="Viton" >Viton</a> and <a href="http://en.wikipedia.org/wiki/Polytetrafluoroethylene" title="Polytetrafluoroethylene" >polytetrafluoroethylene (Teflon)</a> parts. <sup id="cite_ref-16" class="reference" ><a href="http://en.wikipedia.org/wiki/Hydrofluoric_acid#cite_note-16" >[17]</a></sup></p>