Quickly review the presentation that was given by clean room staff and understand how harmful many of the chemicals are in the clean room.

Hydrofluoric Acid (HF)

• Highly corrosive, readily penetrates the skin, causes deep tissue layer destruction and destruction of bone, pain may be delayed from 1 to 8 hours, therefore early treatment is very important.  Use calcium gluconate gel for treatment. Calcium gluconate gel is located next to every fumehood in the cleanroom. Users should apply the entire tube to the affected region as it is a one-time use item.
• Literature indicates that HF exposures of as little as 2% of body area have been fatal.

Nitric Acid

• Corrosive.  Effects may include irritation of the nose and throat, labored breathing, as well as lung (pulmonary) edema, damage to the mucous membranes and upper respiratory tract.  Onset can be several hours after exposure, after initial symptoms have subsided and victim appears fully recovered. Characterized by frothy pink sputum. Fatal if untreated.

Resist Remover RR2, RR4 Dimethyl sulfoxide (DMSO)

• Used as a carrier for experimental drugs.  Penetrates skin, latex.  Will “carry” whatever it contacts through intact skin into the bloodstream.

Piranha

• Most common: 3:1 sulfuric acid (H₂SO₄) : hydrogen peroxide (H₂O₂).   Also used is the base piranha:  3:1 ammonium hydroxide (NH₄OH) with hydrogen peroxide (H₂O₂).  Both are equally dangerous when hot.  Acid piranha is self-starting whereas base piranha must be heated to 60 degrees to begin reaction.  Always add the peroxide to the acid. The H₂O₂ is added immediately before the etching process because it immediately produces an exothermic reaction with gas (pressure) release.  If the H₂O₂ concentration is at 50% or greater, an explosion could occur.  
• Storing already mixed piranha is not allowed.  Piranha in a closed container will likely explode, therefore should NEVER be stored (especially in a glass container).  Used piranha should be left in an open container to cool (several hours) before disposal or poured down the drain while the city water is running.