Clean Hands Dirty Hands
How much bacteria is eliminated by washing your hands?
What's needed:
Blood agar petri dishes (10)
Swabs
Tape
Items commonly touched by many different people, will contain more bacteria than items not commonly touched.
Hands get dirty easily and carry bacteria. Washing your hands with an antibacterial soap will eliminate most bacteria.
- Mark each dish with "Before Washing" and "After Washing".
- Streak a damp swab over an unwashed hand.
- Smear the swab in fast back and forth motion covering the agar from each sample on the plate.
- Repeat steps 2 and 3 after washing your hands with an antibacterial soap.
- Cover the dishes and seal shut with tape.
- Store dishes upside-down in a dark dry area at room temperature. (furnace room works best)
- Between 24 to 48 hours observe the plates. Spores and discolorations represent bacteria. Observe the amount of bacteria that is eliminated by good hygiene.