GENERAL LAB RULES & SAFETY PRECAUTION

Personal Protective Equipment (PPE)

  • any equipment or clothing worn to minimize exposure to hazards that could cause injury or illness in the laboratory

  1. Lab Coat

    • protects your body and clothes from spills and splashes

  2. Safety goggles

    • shields your eyes from chemicals, glass shards, harmful light

  3. Gloves

    • prevents skin contact with hazardous substances

  4. Face mask or respirator

    • protect against inhalation of harmful particles or vapors

  5. Closed-toe shoes

  • prevent foot injuries from spills or dropped objects

Conduct Inside the Laboratory

  1. Prepare Before Entering

    • read and understand all written and verbal instructions for the experiment

    • ask the instructor about anything unclear before starting

  2. No Unauthorized Handling

    • Don’t touch equipment, chemicals, materials until instructed

  3. No Eating, Drinking, or Smoking

    • Never use lab glassware for food and beverages

  4. Perform Only Authorized Experiments

    • Never taste or directly smell chemicals

    • if needed, waft vapors toward your nose

  5. Keep Personal Items Away

    • store belongings away from work areas

  6. Maintain Cleanliness

    • keep workspace neat and free from clutter

  7. Know Safety Equipment Locations

    • be familiar with first aid kit, eyewash station, safety shower, spill kit, fire extinguisher, fire blanket, fire alarms, and emergency exits

  8. Work Carefully and Stay Alert

    • report unsafe conditions immediately

  9. Dispose of Waste Properly

    • follow instructions for chemical waste disposal

    • do not mix chemicals in sinks unless told

    • place solid waste in designated containers

  10. Check Label and Instructions

    • read labels before using any apparatus or chemicals

  11. Practice Good Hygiene

    • Avoid touching your face and wash hands thoroughly after experiments

  12. Clean Up After Work

    • wipe and dry work surfaces after use

  13. End-of-Sesseion Procedures:

    • shut off the main gas outlest

    • turn off the water faucet

    • clean desk, floor, and skin

    • ensure all equipment is cool, clean, and stored properly

Material Safety Data Sheet (MSDS)

  1. Blue (Health hazard)

    • potential harm to human health

  2. Red (Fire hazard)

    • how flammable the substance is

  3. Yellow (Instability hazard)

    • how unstable or reactive the substance is

  4. White (Specific hazard)

    • lists of special hazards like acid (ACID), oxidixers (OX), and radition

Proper Handling of Chemicals & Equipment

  1. treat all chemicals as hazardous unless told otherwise

  2. review the Material Safety Data Sheet (MSDS) for each chemical before use

  3. understand the properties and hazardous of chemicals prior to handling

  4. double-check labels before taking chemicals from containers

  5. never return excess reagents to stock bottles; dispose of them as directed

Handwashing

  1. wet hands with water

  2. apply enough soap to cover all hand surfaces

  3. rub hands palm to palm

  4. right palm over left dorsum with interlaced fingers and vice versa

  5. palm to palm with fingers interlaced

  6. back of fingers to opposing palms with fingers interlocked

  7. rotational rubbing of left thumb clasped in right palm and vice versa

  8. rotational rubbing, backwards and forwads wuth clasped fingers of right hand in left paln and vice versa

  9. rinse hands with water

  10. dry thoroughly with single use towel

  11. use towel to turn off faucet

  12. and your hands are safe

Wearing of Sterile Gloves

  1. open the sterile gloves on dry, flat, clean work surface

  2. remove the outer package by separating and peeling apart the sides of the package

  3. grasp the iiner package and lay it on a clean, dry, flat surface at waist level

  4. open the top flap away from your body; open the bottom flap toward your body

  5. open the side flaps without contaminating the inside of the wrapper or allowing it to close

  6. With your nondominant hand, use your thumb and index finger to only grasp the inside surface of the cuff of the glove for your dominant hand.

  7. Lift out the glove, being careful to not touch any surfaces and holding the glove no more than 12-18 above the table without contaminating the sterile glove; carefully pull the glove over your hand.

  8. Use your nondominant, nonsterile hand to grasp the flap of the package, and hold the package steady. With the sterile glove on your dominant hand, hold 4 fingers together of the gloved hand to reach in the outer surface of the cuff of the sterile glove, reaching under the folded cuff and with the thumb outstretched to not touch the second sterile glove. Lift the glove off the package without breaking sterility

  9. While holding the fingers of the nondominant hand outstretched and close together, tuck your thumb into the palm, and use the sterile dominant hand to pull the second sterile glove over the fingers of the nondominant hand.

  10. After the second sterile glove is on, interlock the fingers of your sterile gloved hands, being careful to keep your hands above your waist.

  11. Do not touch the inside of the package or the sterile part of the gloves with your bare hands during the process.

  12. Maintain sterility throughout the procedure of donning sterile gloves.

Removing of Sterile Gloves

  1. Grasp the outside of one cuff with the other gloved hand. Avoid touching your skin.

  2. Pull the glove off, turning it inside out and gather it in the palm of the gloved hand.

  3. Tuck the index finger of your bare hand inside the remaining glove cuff and peel the glove off inside out and over the previously removed glove.

  4. Dispose used gloves appropriately.

  5. Perform hand hygiene

Pipette

  • glass or plastic tubes, usually open at both ends

  • used to transfer specific amounts of liquid from one container to another

  1. Based on Design

    • To Container (TC)

    • To Deliver (DC)

  2. Based of Drainage

    • Blow out

    • Self-Draining

  3. Based on Use

    • Measuring or Graduated

    • Volumetric or Transfer

Based on Design

  1. To Contain

    • Contains a particular volume but does not dispense the exact volume

    • rinse out pipette (diluting fluid)

    • small amount of fluid will cling to the inside wall of the pipette

  2. To Deliver

    • dispense the amount of volume indicated

    • designed to be drained by gravity

    • must held vertically and the tip placed against the side of container and must not touch the liquid in it

    • small amount of fluid will remain in the tip of pipette

    • meet requirements of transfer pipettes

Based on Drainage

  1. Blowout

    • has continous etched ring or two small continous rings located near the top of pipette

    • last drop should be expelled into the receive vessel

  2. Self-Draining

    • allows the content to drain by gravity

    • tip of pipette should bot be in contact with the accumulating fluid in the receiving during drainage except Mohr pipette

Based on Used

1. Measuring or Graduated

  • deliver the amount of liquid contained between two calibration marks

  • not calibrated with sufficient tolerance to use in measuring standard or control solutions

  • types - serologic, mohr, becteriologic, ball, kolmer or kahn, micropipette

  1. Transfer

    • designed for general liquid transfer, not for precise measurement

    • types - volumettic, ostwald-folin, pasteur pipettes, automatic macropipette, automatic micropipettes

    • Ostwald-Folin (5mL) - for viscous fluids and Blow out

    • Volumetric Pipette - used to deliver single specific volume of liquids, between 1 and 100 mL

    • Pasteur Pipette - used to transfer solutions without consideration of a specifc volume

Types of Automatic Pipette

  1. Air Displacement

    • most routinely used

    • relies on piston for suction creation to draw the sample into a disposable tip that must be changed for used

    • piston does not come in contact with the liquid

  2. Positive Displacement

    • loving the piston in the pipette tip

    • like syringe

    • doesn’t require different tips

    • rinsing and blotting between samples may be required

    • has plunger that will be used to pull that serves as an aspirator

POSITIVE DISPLACEMENT

Pipette Bulbs

  • used to draw liquid up to the pipette

Type of Pipette Bulbs

  1. rubber bulb

  2. pipette filler

  3. pipette aid

  4. pipette pumper

Pipette Tips

  • 100μL to 1000μL (1mL)(Blue)

  • 2μL to 20μL (yellow)

  • 10μL to 100μL (yellow)

  • 5μL to 10μL (white)

Meniscus

  • curvature in the top surface of the liquid

  • pipette should be helf that the calibration mark is at the eye level

  • Lower Meniscus - clear solutions, Concave, Positive

  • Upper Meniscus - colored or viscous solutions, Convex, Negative

Automatic Pipetting Procedure

  1. Double check the information.

  2. Wear PPES

  3. Secure the appropriate tip and adjust the delivery volume.

  4. Depress the piston to the pipettor's stop position.

  5. Insert the tip into the solution and slowly return the piston to its original position.

  6. Wipe off the outside of the pipette with the gauze or tissue and pressed the piston against the receiving vessel's wall.

  7. Follow the first stop and second stop motion to achieve proper dispensing, dispensed exact volume.

  8. Accuracy error is less than 1%

  9. Place the tip in a waste disposal container.

  10. Clean the working area and materials.