ORIENTATION TO THE MICROBIOLOGY LABORATORY

ORIENTATION TO THE MICROBIOLOGY LABORATORY

LABORATORY OBJECTIVES

• To teach concepts of microbiological techniques using critically selected and tested experiments.
• Students will be taught through lectures and demonstrations (during this laboratory portion of the course) on such topics as effective hand washing, aseptic techniques, bacterial cultivation, cultural characteristics of bacteria, interpretation of laboratory results, labeling, and essential recording of their observations.
• Students will be taught how to use a Compound microscope including use of oil immersion lens, how to conduct staining (through instructor demonstrations and continual, active assistance with your professor during the lab period), as well as how to identify unknown species based on morphology, staining and biochemical results.
• Students will be taught how to test and analyze antimicrobial products and be instructed (through demonstrations and ongoing assisting of students) how to perform other means of controlling microbial growth. Your instructor will be actively involved during your entire laboratory session to teach proper techniques and be involved in assisting in lab safety.

STUDENT CONDUCT IN LABORATORY

• To reduce the risk of infection, do not smoke, eat, drink, or bring food or drinks into the laboratory room - even if lab work is not being done at the time.
• Do not apply cosmetics or handle contact lenses in the laboratory.
• Wash your hands thoroughly with soap and water before working in the lab, after handling living microbes, and before leaving the laboratory at any time. Also, wash your hands after removing gloves.
• Do not remove any organisms or chemicals from the laboratory.
• Lab time is precious, so come to lab prepared for that day’s work. Figuring out what to do as you go along is likely to produce confusion and accidents.
• Work carefully and methodically. Do not hurry through any laboratory procedure.

BASIC LABORATORY SAFETY

• Wear protective clothing (i.e., a lab coat) in the laboratory when handling microbes. Remove the coat prior to leaving the lab and autoclave it regularly.
• Do not wear sandals or open-toed shoes in the laboratory.
• Wear eye protection whenever you are heating chemicals, even if you wear glasses or contacts.
• Turn off your Bunsen burner when it is not in use. In addition to being a fire and safety hazard, it is an unnecessary source of heat in the room.
• Tie back long hair, as it is a potential source of contamination as well as a likely target for fire.
• If you are feeling ill, go home. A microbiology laboratory is not a safe place if you are ill.
• If you are pregnant, immune compromised or taking immunosuppressant drugs, please see the instructor. It may be in your best long term interests to postpone taking this class. Discuss your options with your instructor.
• If it is your lab’s practice to wear disposable gloves while handling microorganisms, be sure to remove them each time you leave the laboratory. The proper method for removal is with the thumb under the cuff of the other hand’s glove and turning it inside out without snapping it. Gloves should then be disposed of in the container for contaminated materials. Then, wash your hands.
• Wear disposable gloves while staining microbes and handling blood products - plasma, serum, antiserum or whole blood. Handling blood can be hazardous, even if you are wearing gloves. Consult your instructor before attempting to work with any blood products.
• Use an antiseptic (e.g., Betadine) on your skin if it is exposed to a spill containing microorganisms. Your instructor will tell you which antiseptic you will be using.
• Never pipette by mouth. Always use mechanical pipettors.
• Dispose of broken glass or any other item that could puncture an autoclave bag in an appropriate “sharps” or broken-glass container.
• Use a fume hood to perform any work involving highly volatile chemicals or stains that need to be heated.
• Find the first-aid kit, and make a mental note of its location.
• Find the fire blanket, shower, and fire extinguisher, note their locations, and develop a plan for how to access them in an emergency.
• Find the eye wash basin, learn how to operate it, and remember its location.

REDUCING CONTAMINATION OF SELF, OTHERS, CULTURES, AND THE ENVIRONMENT

• Wipe the desktop with a disinfectant (e.g., Amphyl or 10 % chlorine bleach) before and after each lab period. Never assume that the class before you disinfected the work area. An appropriate disinfectant will be supplied. Allow the disinfectant to evaporate; do not wipe it dry.
• Never lay down culture tubes on the table; they always should remain upright in a tube holder. Even solid media tubes contain moisture or condensation that may leak out and contaminate everything it contacts.
• Cover any culture spills with paper towels. Soak the towels immediately with disinfectant, and allow them to stand for 20 minutes. Report the spill to your instructor. When you are finished, place the towels in the container designated for autoclaving.
• Place all non-essential books and papers under the desk. A cluttered lab table is an invitation for an accident that may contaminate your expensive school supplies.
• When pipetting microbial cultures, place a disinfectant - soaked towel on the work area. This reduces contamination and possible aerosols if a drop escapes from the pipette and hits the tabletop.

DISPOSAL OF CONTAMINATED WASTES

• In most instances, the preferred method of decontaminating microbiological waste and reusable equipment is the autoclave or pressure cooker.
• Remove all labels from tube cultures and other contaminated reusable items and place them in the designated Autoclave container. This will likely be an open Autoclave pan to enable cleaning the tubes and other items following sterilization.
• Disposal of plate cultures (if plastic Petridishes are used) and other contaminated non-sharp disposable items in the designated autoclave container. Petridishes should be taped closed (Note: To avoid recontamination of sterilized culture media and other items, Autoclave containers are designed to be permanently closed, autoclaved, and discarded. Therefore, do not place reusable and non-reusable items in the same container).
• Dispose of all blood product samples and disposable gloves in the container designated for autoclaving.
• Place used microscope slides of bacteria in a “sharps” container designated for autoclaving, or soak them in disinfectant solution for at least 30 minutes before cleaning or discarding them. Follow your laboratory guidelines for disposing of glass.
• Place contaminated broken glass and other sharp objects (anything likely to puncture an autoclave bag) in a sharps container designated for autoclaving. Uncontaminated broken glass does not need to be autoclaved, but should be disposed of in a specialized broken glass container.