Safety

The following aspects of lab safety are addressed.

Protective Clothing

The following protective clothing must be worn at all times while in the laboratory :

Prescription Glasses are acceptable. Wearing contact lenses is discouraged, since they greatly increase the likelihood of permanent eye damage should a chemical splash contact the eye. If you wear contact lenses, be sure to notify the instructor so that proper care can be given if necessary.

General Guidelines

  1. No open-toe sandals, bare feet, or SHORTS are allowed in the lab.
  2. All work with acids and solvents must be done under an exhaust hood. This includes opening bottles.
  3. Never pour excess chemicals back into the origional bottle. Discard excess acid into sinks with the tap running, and discard organic solvents into the solvent waste bottle under the fume hood.
  4. Wash your hands after handling chemicals.
  5. Food or beverages are not allowed inside the lab.
  6. Clean up your work area during and after use. DO NOT leave hazards for others.
  7. Material Safety Data Sheets are available in the lab for all chemicals used. The instructor will be familiar with these, in case of accidental contact. You should also be familiar with safety procedures, in case of a spill of a particular chemical.

  8. Familiarize yourself with the locations of chemical showers and eye washes.
  9. Emergency phone numbers are posted near the telephone in the lab. Campus Police can be reached at 4-2500
  10. Report all safety violations and hazards to the instructor.

Chemical Safety

Acid Handling

  1. In case of accidental contact with and acid, flush immediately with copious amounts of runnig water. All burns must be reported to the instructor immediately.
  2. When mixing solutions containing acids

    ALWAYS ADD ACID TO WATER

    Begin pouring acids slowing. Violent reactions may occur if mixed incorrectly. This is espically true when mixing sulfuric acid.
  3. After mixing acid solutions, allow solutions to cool thoroughly before capping. Heat is generated after mixing, which can cause pressure in a capped bottle.
  4. After use, always cap acid bottles tightly.
  5. All chemicals poured into a sink will mix in the piping --- please run lots of water between chemicals, and before and after dumping any chemicals into the sink.
  6. Keep in mind that while other fumes from chemicals are merely strong irritants or corrosive, hydrofluoric acid (HF), including buffered oxide etch (BOE), is letal if inhaled.

DANGER --- HYDROFLUORIC ACID (HF)

Hydrofluoric acid does not produce overt tissue burns like most acids. However, HF does diffuse through tissue and dissolve bone. Whereas other acids, bases, and solvents are strong irritants, cumulative poisons, or carcinogenic, HF fumes can be fatal.

For these reasons, particular caution should be exercised when handling HF.

Immediately report any possible contact to the instructor.

Solvent Handling

  1. Organic solvents, such as acetone and trichloroethylene, will react with acids or other strong oxidizing materials, such as hydrogen peroxide. DO NOT MIX THEM. A mixutre of nitric acid and acetone, for example, is highly explosive.
  2. Solvents should be poured into the waste solvent bottle located in the fume hood.
  3. Most solvents present some degree of toxic hazards when their fumes are inhaled over a prolonged period. Always work with solvents in an exhausted hood.
  4. Avoid getting solvents onto the skin. Solvents are readily absorbed through the skin and into the bloodstream. Some solvents, such as trichloroethylene, are carcinogenic.
  5. Solvents are generally quite flamable. Though there are few ignition sources in the lab, always be cautious near any source of a spark.
  6. Photoresist contains organic solvents as part of its makeup. These solvents can be as hazardous or more so than the other solvents used in the lab. Avoid skin contact or breathing the fumes of photoresist.

DANGER --- MERCURY VAPORS AT ROOM TEMPERATURE

Mercury evaporates at room temperature, and is highly toxic. Notify the instructor if you break a thermometer or spill mercury.

UV light sources (present in mask aligners) are normally quite safe. However, when these lamps approach their useful end, they can overheat and explode. This releases toxic mercury fumes into the room. Should this happen, immediately leave the area and notify the instructor.

After turning off a normal UV lamp, it must cool for 30 minutes before restarting. Failure to do so may result in a bulb explosion.

What to do if an accident occurs

  1. Provide immediate attention to those involved.
    If a chemical came in contact with skin, take the person to eye wash station and rinse the skin.
    If HF came in contact with your skin, rinse and than apply the ointment located next to the spill containment materials. This creme will slow the flourine ions from penetrating into your skin.

    There is a First Aid Kit and a fire extinguisher on the wall near the door.

    To operate the eyewash, remove the plastic cover and push on the red lever to turn on the water.

  2. Call the instructor and Campus Police(4-2500). There is a list of emergency phone numbers on the wall by the telephone.
  3. If chemicals are spilled, then contain the spill after attending to the injured person.
While getting dressed, it would be a good idea to read the poster on emergengy procedures located above the dressing area until you are completely familiar with it.

Cleanup of Spills

Back to the Process Page.