Disposing of Waste
Solid biohazardous waste should be autoclaved in the kill autoclaves in the Biochemistry Building at 121 °C for an hour. Close the plastic waste bag, leaving a small opening at the top so that steam can enter and escape. Place the bag in an autoclave-safe tray, and place heat-sensitive tape over the biohazard symbol. After autoclaving, allow the bag to cool, place it in a black garbage bag, and then dispose of it in the dumpster.
To dispose of liquid biohazardous waste, add 10% bleach to the container, let it sit for a minimum of 20 minutes, and then pour it down the drain.
To clean up a biological spill, cover the spill with paper towels and soak in undiluted bleach for an hour. Discard the paper towels in a biohazard waste bin, re-wipe the area with disinfectant, and wash your hands.
Neutralize acid spills before cleaning up.
- Use autoclave gloves when loading/unloading the autoclave. A face shield can also be used.
- Fill containers to under 75% capacity.
- Loosen all caps before autoclaving, and tape them on one side.
- Make sure the pressure is at zero before opening the autoclave.
- Do not change the temperature on the autoclaves in the Biochemistry Building.
Autoclave for 30 minutes using the liquid cycle. After autoclaving, crack the door to release steam and then slowly open the door. To prevent explosion of superheated liquids, allow liquids to cool slightly before removing the tray.
Autoclave for 30 minutes using the gravity cycle, then move to the dryer overnight.
Do Not Autoclave...
- Hazardous chemical waste such as bleach, ethidium bromide, HCl, and chloroform.
- Non-heat-resistant plastics such as polystyrene and polyethylene.
- Radioactive waste.
The pH Meter
- Rinse the pH probe with water before use.
- If necessary, calibrate the pH meter according to the instructions posted on the wall. At least check the calibration using the pH 7 buffer solution.
- Slide the tubing near the top of the pH probe up or down to open the vent, and close again when finished.
- If the vent gets covered with gunk, wipe it off with a paper towel, don't rinse with water.
- Don't let the filling solution get below the coil. If it completely dries out, rinse the probe with water before refilling.
- When taking measurements, make sure that the bulb and junction of the probe are submerged. Make sure that the stir bar does not break the bulb.
- When finished, rinse with water and put the probe back in the storage solution.