These activities can lead to body contamination with harmful microorganisms.
Miscellaneous. Sitting on the laboratory bench is not permitted. Keep the laboratory as neat as possible at all times. At the end of each laboratory period, check and arrange all materials neatly. Return all materials to their proper places or dispose of them appropriately when your work is finished.
Never remove equipment, media, or microbial cultures from the laboratory.
Label all materials properly so that they can be identified easily. Tubes should be labeled using label tape and a marker. Petri dishes should be labeled on the bottom (the side with the agar) with student name, the organism, type of medium, incubation temperature, and date.
Use pipettes carefully. Pipettes can be hazardous if not used properly. Mouth pipetting is both a poor technique and a safety hazard; therefore, it is not permitted. Pipette bulbs, manual pipette aids, and semiautomatic pipetters (with pipette tips) are available for use. Forcing a pipette into either a bulb or a pipette aid may lead to breakage and should be avoided. It should be cautioned that improper use of pipettes can lead to dripping or generation of hazardous aerosols.
Be familiar with the available safety equipment and supplies. Know the locations of the first‐aid kit, safety showers, eyewash stations, fire extinguishers, fire blankets, and fire alarms.
Avoid fire hazards. Hair that is shoulder length or longer must be tied back or pinned up to minimize the risk of it catching on fire. Similarly, hats with brims should be avoided as the brim might come near the flame. Hats such as baseball caps may be worn facing backward to keep the brim away from flames. For safety, constantly be aware of any burners near you. Always use your own burner. Do NOT reach across the bench to use someone else’s burner. Some of the liquids present in the laboratory are flammable; keep these away from the Bunsen burner.
Handling fire emergencies.Students should be aware of the location of available fire safety equipment (e.g., fire extinguishers, fire blankets) and the nearest exits in case of larger fires.Alcohol fires are among the most common laboratory fires. Should a jar of alcohol catch fire, placing the lid over the jar quickly may suffocate the fire. Alternatively, cover the burning jar with a slightly bigger glass jar, such as a beaker. Keep flame away from staining bottles as these often contain alcohol.If anyone’s hair or clothing should catch on fire, obtain a fire blanket, wrap the person in the blanket, and have them roll on the floor to extinguish the flames.Any fire should be reported immediately to the laboratory supervisor.If a major fire occurs, proceed to the nearest exit. DO NOT USE ELEVATORS!
Handling first‐aid emergencies.Students should be aware of the location of the first‐aid kit in the laboratory. The kit should contain gauze bandages, adhesive bandages, bandage tape, sterile swabs, burn cream, antiseptic wipes, and hydrogen peroxide.Get the instructor’s assistance before using the first‐aid kit.
Mercury spills. While many laboratories have switched from mercury to alcohol thermometers, some laboratories may still be using mercury thermometers. Mercury is a hazardous material that requires special cleanup procedures. If a mercury thermometer is broken, the analyst should notify the instructor immediately. The students in the vicinity of the spill should not touch the mercury, should move away from the area, and should prevent others from entering the area.
No bicycles, skateboards, roller skates, or similar devices are permitted in the laboratory or the hallway. These items can create a tripping hazard in the laboratory, to passersby in the hall, or during an emergency.
Report any personal injuries to the laboratory instructor/supervisor. In case of accidents, mandatory accident reporting forms must be filled out as soon as possible.
MATERIALS IN MICROBIOLOGY LABORATORY
In many teaching laboratories, each student (or a group of students) is assigned a storage drawer (or a similar compartment) containing materials commonly used in the laboratory. Students should be sure that the drawer contains all the materials indicated in the course instructions and that all materials are returned and stored at the end of each session. Typical tools contained in this storage space may include inoculating loop, inoculating needle, microscope slides, cover slips, microscope lens cleaner, lens cleaning paper, lens oil, wax marking pencils or permanent markers, pipette bulbs, bibulous paper, and matches or a striker for lighting the Bunsen burner. Some of the consumable materials may be used up during the course of the term and students should learn where replacement materials are kept. At times, the items from a storage location may be misplaced. If this occurs, the student should not take supplies from someone else’s drawer.
Some laboratory communal supplies may also be used up during the course of the school term. These items may include paper towels, disinfectant solutions, Gram stain reagents, other staining agents or reagents, adhesive tape, and other frequently used materials. Students should determine where these items are stocked so that they can replenish supplies.
Students should know where to obtain distilled water. In most laboratories, special distilled water taps are used; these are often located near the regular hot‐ and cold‐water taps. The distilled water taps are frequently spring‐loaded to prevent anyone from leaving the tap open and wasting water. Often these taps have a tab on the handle labeled “DW.”
At the beginning of every laboratory session, the student should determine the location of all water baths, incubators, or other equipment that will be shared during that session. Students should collect all media and supplies required to perform the experiment. Many microbiological growth media look similar; therefore, caution should be taken to carefully and correctly label media. Students should not collect more media than will be used during the exercise. Careful reading of the laboratory exercise should allow students to determine the correct number of plates and tubes needed for each exercise.
The microbiology laboratory contains many materials that are potentially dangerous if used outside the laboratory environment. Students should never remove slides, plates, or tubes from the laboratory. After use in the laboratory, materials are either prepared for reuse or discarded. Each laboratory has a system for material disposal, protocols for which items are reused and which are discarded, locations where reusable materials should be placed at the end of the laboratory, expectations for what to clean manually by students, etc. Students must be familiar with proper disposal and proper clean up to ensure that materials are not wasted, biohazard containers do not contain excess materials, and everyone’s safety is preserved.
Used culture tubes should not be returned to the laboratory exercise set‐up area, unless the instructor specifically tells students to do so. Only unused media should be returned to the set‐up area.
Reusable materials may include some glassware, such as test tubes, bottles, and flasks. This reusable glassware should then be placed in the designated location for each type of item. Depending on their contents, tubes, bottles, and flasks may need to be autoclaved before washing. These items should be separated from items that do not require autoclaving. Some other items, such as blender jars, may not require autoclaving and may be manually washed by students. These items should be washed according to the designated protocol and placed in the designated drying area.
Non‐reusable materials are disposed of in either hazardous or non‐hazardous waste containers. Paper towels used with disinfectant to wipe off laboratory benches may be placed in the containers for non‐hazardous waste (i.e., regular trash). Gauze or lens paper used to clean microscope lenses before or after use is also safe to be placed in the regular trash. Items that have not been exposed to microorganisms do not require special disposal.
Biohazard containers
