Chapter I General safety rules in Microbiological Laboratory Flashcards
the application of safety precautions that reduce a laboratorian’s risk of exposure to a potentially infectious microbe and limit contamination of the work environment and, ultimately, the community.
Biosafety
Four biosafety levels
Biosafety level 1
Biosafety level 2
Biosafety level 3
Biosafety level 4
organisms are well-characterized strains of microorganisms
not known to cause disease in healthy human adults.
Biosafety level 1
organisms include in this biosafety level are non-pathogenic laboratory strains of Escherichia coli, Staphylococcus xylosus, and Bacillus megaterium.
Biosafety level 1
Organisms are moderate-risk microorganisms associated with less serious human diseases whose potential for transmission is limited and a proven treatment for the disease exists.
Biosafety level 2
pathogens are opportunistic, particularly in children and immunocompromised adults. Additional precautions in this biosafety level include using personal protective equipment (PPE) such as disposable gloves and laboratory coats and limiting lab access to trained individuals.
Biosafety level 2
Organisms are high-risk microorganisms with a true potential for infection by aerosols and in which the resulting disease may have serious or lethal consequences.
Biosafety level 3
organisms include Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella
Biosafety level 2
Researchers in this biosafety level generally wear double gloves, respirators, and disposable surgical scrubs and gowns, and work in biological safety cabinets in isolated, negative-pressure containment rooms.
Biosafety level 3
organisms include Mycobacterium tuberculosis, Foot-and-mouth disease virus, and Bacillus anthracis.
Biosafety level 3
organisms include Avian flu viris, Ebola virus, Marburg virus, and Lassa fever virus.
Biosafety level 2
organisms are easily transmitted, very-high risk microorganisms which cause life-threatening diseases for which there is no vaccine or therapy.
Biosafety level 4
Laboratories work in impermeable positive pressure “space suits” with an external oxygen supply, and precautions such as chemical showers must be taken before exiting the lab.
Biosafety
A very important biosafety practice. Incidents involving biological, chemical, physical, and radiological hazards can have a significant impact on the safety and health of those who work in laboratory settings.
Microbiological risk assessment
Steps of risk management
Step 1: Identify the hazard and risk
Step 2: Evaluate the risk
Step 3: Implement a risk mitigation plan, as needed
Step 4: Evaluate the effectiveness of controls
Ask what, where, and how the work is occurring and who is doing the work. Then, determine what could go wrong in every step of the activity or procedure and the result of the undesirable incident (e.g., injury, exposure, infection, disease).
Identification of the hazards and risks
Characterize the risks
Likelihood of the risk
Consequence of risk
Risk evaluation
Example; strictly implement proper disposal of waste (ie sharps)
Risk mitigation plan
How to conduct risk assessment?
- Identification of the hazards and risks
- Risk evaluation
- Risk mitigation plan:
- Evaluation of effectiveness of control
Example ; needle sticks or broken glass (slides, cover slips, beakers etc)
Characterize the risks
Example; absence of proper disposal of sharp objects
Likelihood of the risk
Example; cuts, or potential infection from exposure to biological
agents
Consequence of risk
Classification of infective microorganisms
- Risk Group 1 (no or low individual and community risk) 2. Risk Group 2 (moderate individual risk, low community risk)
- Risk Group 3 (high individual risk, low community risk)
- Risk Group 4 (high individual and community risk)
A microorganism that is unlikely to cause human or animal disease.
Risk Group 1 (no or low individual and community risk)
A pathogen that can cause human or animal disease but is unlikely to be a serious hazard to laboratory workers, the community, livestock or the environment. Laboratory exposures may cause serious infection, but effective treatment and preventive measures are available and the risk of spread of infection is limited.
Risk Group 2 (moderate individual risk, low community risk)
A pathogen that usually causes serious human or animal disease but does not ordinarily spread from one infected individual to another. Effective treatment and preventive measures are available.
Risk Group 3 (high individual risk, low community risk)
A pathogen that usually causes
serious human or animal disease and that can be readily transmitted from one individual to another, directly or indirectly. Effective treatment and preventive measures are not usually available.
Risk Group 4 (high individual and community risk)
an enclosed, ventilated laboratory workspace for safely working with materials contaminated with (or potentially contaminated with) pathogens requiring a defined biosafety level. It is intended to offer protection to the user and environment from the aerosol hazards arising from the handling of infected and other hazardous biological material.
biosafety cabinet (BSC)—also called a biological safety cabinet or microbiological
safety cabinet
types of safety cabinet
Class I
Class II
Class III
Safety cabinet with front opening through which the operator can carry out manipulations inside the cabinet and which is constructed so that the worker is protected and the escape of airborne particulate contamination generated within the cabinet is controlled by means of inward airflow through the working front opening and filtration of the exhaust air.
Class I BSC
safety cabinet with front opening through which the operator can carry out manipulations inside the cabinet and which is constructed so that the worker is protected, the risk of product and cross-contamination is low and the escape of airborne particulate contamination generated within the cabinet is controlled by means of an appropriate
filtered internal airflow and filtration of the exhaust air (laminar airflow).
Class II BSC
Safety cabinet in which the working area is totally enclosed and the operator is separated from the work by a physical barrier (I.e. gloves mechanically attached to the cabinet). Filtered air is continuously supplied to the cabinet and the exhaust air is treated to prevent release of micro-organisms.
Class III BCS
to examine microorganisms which can’t be seen by naked eyes
Microscope
to heat or boil solution in laboratory
Bunsen burner
What’s the function of Autoclave
to sterilize the equipment medias and other solutions
What’s the function of Pressure cooker
to sterilize the equipment medias and other solutions
to preserve the samples, media, reagents and other specimen
Refrigerator
a laboratory device that employs a rotating magnetic field to cause a stir bar (or flea) immersed in a liquid to spin very quickly, thus stirring it.
Magnetic Stirring Plate