PH 156 Laboratory Safety | Clinical Microscopy PDF

PH 156: CLINICAL MICROSCOPY LABORATORY SAFETY Dr. Geraldine B. Dayrit, RMT, Msc, DRDM, PhD | January 28, 2025​ ​ ​ Trans #01...

PH 156: CLINICAL MICROSCOPY LABORATORY SAFETY Dr. Geraldine B. Dayrit, RMT, Msc, DRDM, PhD | January 28, 2025​ ​ ​ Trans #01 BIOSECURITY OUTLINE ​ Aims to prevent unauthorized access, loss, theft, misuse, A.​ Concepts and Definitions diversion or release of microorganisms a.​ Laboratory Safety b.​ Biosafety ​ “Keep people away from bugs” c.​ Biosecurity ​ Elements to ensure biosecurity in the lab: B.​ Principles ○​ Personnel reliability a.​ Hazards ○​ Accountability b.​ Routes of Entry ○​ Information security c.​ Laboratory Signs and Symbols ○​ Response i.​ Safety Signs and Symbols ○​ Physical measures ii.​ Globally Harmonized System (GHS) Pictograms ○​ Transport security d.​ Standard Operating Procedures (SOP) ○​ Management i.​ Personal Protective Equipment (PPE) ○​ Awareness ii.​ Microorganism Resistance to Disinfectants iii.​ Risk Groups and Biosafety Levels Importance C.​ Risk Management Process ​ A review of recent laboratory-associated infections a.​ Identify the Hazards and Risks showed that most were caused by human factors rather b.​ Evaluate the Risks than malfunctions of engineering controls. i.​ Characterize the Risks ​ Factors that have led to potential and confirmed ii.​ Prioritize the Risks and Determine if Risks are exposures to biological agents: Acceptable ○​ An absence or improper use of PPE c.​ Implement a Risk Mitigation Plan ○​ Inadequate or ignored risk assessments i.​ Action Items in Hazard Prevention and Control ○​ Lack of SOPs d.​ Evaluate Effectiveness of Controls ○​ Insufficiently trained personnel D.​ Supplementary Videos ​ It can be argued, therefore, that the best designed and a.​ Laboratory Safety most well engineered laboratory is only as good as its least b.​ Waste Disposal competent worker. c.​ Basic Biosafety d.​ Working Alone in the Lab PRINCIPLES e.​ Pipette Safety and Ergonomics E.​ Review Questions HAZARDS F.​ References Table 1. Different Types of Hazards and Some Examples.. TYPE OF HAZARD EXAMPLES CONCEPTS AND DEFINITIONS Reactives LABORATORY SAFETY Flammables Chemical Toxins ​ Involves recognizing and evaluating hazards, assessing Corrosives risks, selecting appropriate personal protective equipment, Noise and performing the experimental work in a safe manner Projectiles (National Research Council (US) Committee on Prudent Practices in the Laboratory, 2011) Physical Heating Devices Slipping Importance (as discussed during the F2F session) Moving machinery accidents ​ To prevent unnecessary accidents Microbes ​ Wearing PPEs and following protocols and guidelines Plants which were made to protect us while doing and performing Biological Animals our laboratory works Genetically Modified Agents ○​ We must not deviate from the protocol ○​ If we have to change something, we have to inform the others ROUTES OF ENTRY Additional Information (Cornell University, n.d.) BIOSAFETY ​ Contact - may result from a chemical spill or splash to ​ Aims to prevent unintentional exposure to biological unprotected eyes or skin agents or their inadvertent release ​ Ingestion - occurs by absorption of chemicals through the digestive tract ​ “Keep bugs away from people” ​ Inhalation - occurs by absorption of chemicals via the ○​ Bugs being the bacteria, viruses, microorganisms, etc. respiratory tract (lungs) ​ 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 (CDC, n.d.) ​ Elements / Concepts under biosafety: ○​ Containment ○​ Protocols ○​ PPEs ○​ Proper waste management / safe disposal Figure 1. Routes of entry. #MagkabigkisBenteSais Group 1 | 1 of 9  LABORATORY SIGNS AND SYMBOLS ​ Equipment and/or clothing worn by personnel to provide a barrier against biological agents Safety Signs and Symbols ​ Used to minimize the likelihood of exposure to hazards ​ Easily recognizable graphic labels that represent the ​ Includes laboratory coats, gowns, full-body suits, gloves, general protocol and safety instructions in either protective footwear, safety glasses, safety goggles, masks workplaces, establishments, or public spaces (Reyes, 2024 as cited and respirators in Batch 2025 Trans) Supplementary Video: “PPE in the Biological Lab” ​ Scenario: A technician wearing his lab coat but was flaming loops at the bench, ignited some of the alcohol, spilled it, and ignited. It went down the front of his coat. He immediately took the coat off and threw it on the floor and put it out with a fire extinguisher that was nearby. This is very fortunate that he had the coat on and he also knew how to use the fire extinguisher ​ Takeaway: The lab coat, even though it wasn't fire retardant, still slowed the burn enough to protect him from Figure 2. Safety signs and symbols. being injured. This example shows how important it is to wear PPE. It also shows how important it is to take fire Globally Harmonized System (GHS) Pictograms extinguisher training. ​ Even if you have done something for many years, ​ The Globally Harmonized System of Classification and accidents can still happen. It only takes a second for Labelling of Chemicals (GHS) is an internationally something to go wrong, so maintaining situational agreed-upon system to standardize chemical hazard awareness when conducting routine procedures is crucial. classification and communication (International Labor Organization, 2022) ​ Many laboratory-associated infections are due to human ​ Graphic images that immediately show the user of a factors rather than equipment malfunctions. These human factors include: hazardous product what type of hazard is present (Canadian ○​ Absence or improper use of personal protective Centre for Occupational Health and Safety, 2024) equipment (PPE). ○​ Inadequate or ignored risk assessments. ○​ Lack of standard operating procedures (SOPs). ○​ Insufficiently trained personnel. ​ Therefore, even the best-designed and well-engineered laboratory is only as safe as its least competent worker. Proper training and adherence to safety protocols are important for preventing infections. Supplementary Video: “The Beaking Method” ​ A method to remove your gloves efficiently and effectively without contaminating your hands. ​ The “beaking” method was used in the first two cases of Ebola in the United States. ​ It is unethical to provide PPE and not teach how to remove Figure 3. GHS pictograms. it properly, as improper removal can cause contamination * See appendix for an enlarged version of this figure. and put the individual at risk. ​ It is important to focus on how to remove gloves for the STANDARD OPERATING PROCEDURES (SOP) protection of those who work with infectious agents, and ​ A set of well-documented and validated stepwise for the protection of those they live with and the world ​ Steps: instructions outlining how to perform laboratory practices ○​ Involves 10 steps, with the 10th step being the most and procedures in a safe, timely and reliable manner, in important (washing hands with soap and water) line with institutional policies, best practice and applicable i.​ Form an "L" with the left hand national or international regulations (WHO, 2020) ii.​ Grab the cusp of the glove ​ “General Lab Safety Rules” iii.​ Pinch the middle of the glove upward ○​ Housekeeping safety rules iv.​ Scoop under with the middle finger ○​ Dress code safety rules v.​ Form a beak and then cover that beak. vi.​ Use the beak and grab the top, keeping your index ○​ Personal protection safety rules fingers in front. ○​ Chemical safety rules vii.​ Inside out bring the glove down. ○​ Electrical safety rules viii.​ Flip over give yourself a five single finger down the middle. Personal Protective Equipment (PPE) ix.​ Push it down. x.​ Wash hands with soap and water ○​ When using the “beaking” method, do not touch the skin with the dirty glove. ○​ Many people are copying the “beaking” method but are not doing it correctly. ○​ If you grab the glove at the top and turn your hand, you could touch your skin, which is not ideal. ○​ Healthcare providers and laboratory personnel remove hundreds of gloves a day; this method should become a habit. ​ Additional information: ○​ You can test your glove removal technique by covering your gloves with Glo germ or chocolate sauce, removing Figure 4. Personal protective equipment. PH 156 | Laboratory Safety 2 of 9  them with your eyes closed, and then checking for ​ Determine potential hazards (e.g., biological, chemical, contamination. physical) and their sources ○​ Cuts, rips, and tears in the cuticles of the fingers can ○​ Chemical: e.g., reactives, toxins, corrosives, increase the risk of contamination flammable. ○​ Physical: e.g., noise, projectiles, heating devices, Microorganism Resistance to Disinfectants slipping, moving machinery accidents. ○​ Biological: e.g., microbes, plants, animals, genetically-modified agents ○​ Routes of Entry: ​ Contact, Ingestion, Inhalation ​ Consider how the work is performed, the location, and the personnel involved ○​ Ask what, where, and how the work is occurring and who is doing the work ​ Identify possible failure points and consequences (e.g., exposure, infection, injury) EVALUATE THE RISKS ​ Risk assessment should evaluate each risk against a standard set of criteria so that the assessed risks can be compared against each other ​ The criteria should focus on both the likelihood of the undesirable incidents occurring and the consequences if those undesirable incidents were to occur Figure 5. Microorganism resistance to disinfectants. Characterize the Risks Risk Groups and Biosafety Levels ​ Includes factors that affect whether or not the incident Table 2. Classification of Microorganisms according to Risk Groups. happens and occurs before the actual incident occurs RISK GROUPS RISK ASSESSMENT ​ Assess the likelihood of an undesirable event based on: 1 No or low individual and community risk ○​ Biological Agent Factors: Moderate individual risk ​ Stability in the environment (e.g., ability to 2 Low community risk produce spores, resistance to disinfectants) High individual risk ​ Potential routes of transmission (direct mucosal 3 Low community risk contact, inhalation, ingestion, injection) 4 High individual risk and community risk ​ Endemicity of biological agent in the local environment and population (e.g., endemic or exotic) and host range ​ Life stage/form of the biological agent (e.g., dimorphic fungi, antigenic shift) ​ Communicability ○​ Laboratory/Testing Environment Factors: ​ Physical infrastructure and existing controls: Type of facility, presence of engineering/safety controls, type of equipment used, function/reliability of ventilation systems ​ Procedural: Existence of administrative controls such as policies and training; availability of appropriate PPE; generation of aerosols and use of sharps; amplification of the biological agent by culturing, and types and complexity of procedures Figure 6. Relation of risk groups to biosafety levels, practices, and equipment being conducted (Tankeshwar, 2013). * See appendix for an enlarged version of this figure. ○​ Human Factors: ​ Competency of personnel, level of training RISK MANAGEMENT PROCESS ​ Behavioral aspects (e.g., stress, risk perception, ​ Risk management is a continuous process to identify, risk tolerance, following safe work practices) assess (evaluate), control, and monitor risks ​ Consequences of Risks ​ Steps: ○​ Consider factors that affect the severity of an incident ○​ Step 1: Identify the hazards and risks. after it has occurred (e.g., infection) ○​ Step 2: Evaluate the risks. ○​ Biological agent factors: ○​ Steps 3-4: Implement a risk mitigation plan, as ​ Virulence factors: adhesion, invasiveness, needed. toxigenesis, production of exoenzymes, antigenic ○​ Step 5: Evaluate the effectiveness of controls. variation, autoantibodies against host ​ High communicability IDENTIFY THE HAZARDS AND RISKS ​ Severity of infection/disease (morbidity/mortality rate) ​ For a specific activity or procedure, identify the hazards in ​ Infectious dose each step or task that must be completed ○​ Administrative controls: ​ Examine each step of a laboratory procedure or activity PH 156 | Laboratory Safety 3 of 9  ​ Availability of vaccines, prophylaxis, therapeutic interventions, and emergency response ​ Elimination procedures ○​ Most important control ○​ Host factors: ○​ Most protective ​ Health and immune status of staff: ​ Substitution immunocompetent or immunocompromised, ○​ Finding an alternative (eg. lesser pathogenic organism) pregnancy, pre-existing medical conditions, ​ Engineering Controls allergies, age, large susceptible population ○​ Ventilation ○​ Behavioral aspects: ○​ Filters ​ Willingness to accept vaccines ○​ Lighting ​ Adherence to safe work practices and proper use ​ Administrative Controls of PPE ○​ Standard operating procedures ○​ Workflow Prioritize the Risks and Determine if Risks are Acceptable ​ PPE ○​ Least protective ​ Risks can be reduced, but cannot be completely ○​ Individual level eliminated unless the work is discontinued entirely or ○​ If you have controlled every level of control before PPE modified to incorporate less harmful activities (Elimination, Substitution, Engineering Controls, ​ Classify risks as: Administration Controls), there is no more need for the ○​ Acceptable: Work can proceed with the existing use of PPE (Dayrit, 2025) controls ○​ Unacceptable: Work cannot proceed until additional EVALUATE EFFECTIVENESS OF CONTROLS mitigation controls are implemented to reduce the risk ​ The effectiveness of implementing additional controls (e.g., to an acceptable level engineering controls, administrative and work practice controls, and use of PPE) should be reviewed and IMPLEMENT A RISK MITIGATION PLAN evaluated ​ For risks that are determined unacceptable by the ○​ Evaluation can be based on the Biosafety in institution, a mitigation control plan should be Microbiological and Biomedical Laboratories (BMBL) implemented (6th Edition) Action Items in Hazard Prevention and Control SUPPLEMENTARY VIDEOS ​ Action Item 1 LABORATORY SAFETY ○​ Employers are provided with information to help them investigate options for hazard control. Before selecting Decontamination for Laboratory Safety any control options, it is essential to solicit workers' ​ 2 categories of decontamination: input on their feasibility and effectiveness ○​ Disinfection ​ Action Item 2 ​ Eliminates NEARLY ALL pathogenic ○​ Select the controls that are the most feasible, microorganisms EXCEPT microbial spores effective, and permanent ○​ Sterilization ​ Action Item 3 ​ Eliminates ALL microbial life ○​ Address serious hazards first ​ Decontamination is carried out using methods such as ○​ Overall goal is to ensure effective long-term control of chemical, heat, or radiation hazards ○​ Choice of method depends on the degree of ​ Action Item 4 contamination + type and concentration of ○​ Should include provisions to protect workers during contaminant non-routine operations (i.e. tasks workers don't normally do) and foreseeable emergencies Choosing a Decontamination Method ​ Action Item 5 ​ Determine the type, concentration, and location of ○​ Once hazard prevention and control measures have microorganism before establishing a decontamination been identified, they should be implemented procedure according to the hazard control plan ○​ Bacteria (Gram positive or Gram negative) ​ Action Item 6 ○​ Viruses ○​ Ensure that control measures are and remain effective, ○​ Fungi employers should track progress in implementing ○​ Bacterial Spores controls, inspect and evaluate controls once they are ○​ Algae installed, and follow routine preventive maintenance ​ After determining the type of microorganism, choose a practices suitable disinfectant ​ Effectiveness of a disinfectant is dependent on factors: ○​ Chemical composition ○​ Amount ○​ Concentration ○​ Contact time ○​ Temperature Disinfecting with Liquid Chemicals ​ 3 levels of liquid chemicals ○​ Low Figure 7. Hierarchy of Controls. ○​ Intermediate PH 156 | Laboratory Safety 4 of 9  ○​ High ​ Prior to commencing any laboratory activity, a waste ​ Most non-critical microorganisms require only low level management system must be devised disinfectants which are low in toxicity but can cause ○​ Often established by an institution’s Environmental irritation upon long exposure times Health and Safety (EH&S) office which enforces ○​ Quaternary Ammonium compounds guidelines imposed by the Occupational Safety and ​ Benzalkonium chloride Health Administration (OSHA) ​ Ammonium chloride ○​ Phenolic compounds Principles of Proper Waste Disposal ​ o-Phenyl-phenol ​ Efficient waste management is an important aspect of ​ Chloroxylenol proper waste disposal ​ For the decontamination of more resistant microorganisms ○​ Accomplished by using the minimal amount of ○​ Alcohol-based chemicals (60-90% solutions) chemicals possible by reusing surplus materials and ○​ Halon-based compounds are often applied as by recycling waste. antiseptics and disinfectants of medical equipment. ○​ Generated waste must be labeled, segregated, However, these agents have prolonged contact times according to chemical compatibility and stored in a and their effectiveness is decreased in the presence of fume hood or other well ventilated area. organic matter. ○​ Other laboratory waste such as sharps and glass must ​ Hypochlorites be disposed with care in appropriate containers. ​ Povidone-Iodide ​ If decontamination of all microorganisms is required Typical Laboratory Procedure ○​ Oxidizers (Acids and Aldehydes) ​ If applicable, keep the chemical waste to a minimum by ​ Hydrogen peroxide reducing the scale of operation. ​ Used as antiseptics for wound cleaning and disinfectant for environmental surfaces Waste Management ​ Exposure to high concentration can be harmful ​ Substitute chemicals with less hazardous reagents if ​ Peracetic acid possible ​ Used in disinfecting automated machines ​ Store only chemical quantities that will be used in the near and sterilizing medical instruments term ​ Formaldehyde and Glutaraldehyde ​ Recycling solvents like acetone using distillation ​ Non-corrosive but still hazardous ​ Wear PPE including lab coat, goggles, and gloves with ​ Used to sterilize various type of equipment long pants and clothes toed shoes whenever handling any but suffer from prolonged contact time chemical ​ Collect chemical waste in suitable containers such as Disinfecting with Gas plastic carboys or glass bottles and store near the point of generation in a designed satellite accumulation area ​ Gases that are frequently used to for closed equipments ​ Affix labels to the waste containers as soon as chemicals such as biosafety cabinets of bacteria, viruses, and spores are added ○​ Chlorine dioxide ​ Write on the labels the full name of the chemicals and their ○​ Ethylene oxide appropriate compositions ○​ Vaporized Hydrogen peroxide ​ Use separate containers for halogenated, ○​ Peracetic acid non-halogenated, and aqueous waste to avoid potential heat or gas formation Disinfecting with Heat and Radiation ​ When containers are filled to capacity, carefully move them ​ Dry Heat to a designated central accumulation area from which they ○​ Disinfect glasswares will be removed for disposal ○​ 160-170°C for 2-4 hours ○​ Not suitable for heat-labile materials Disposal of Sharps and Glass Waste ​ Wet Heat ​ Dispose of chemically contaminated needles, syringes, ○​ Also known as “autoclaving” and razor blades collectively known as sharps inside a ○​ Heating samples and equipment sharps waste container for the broken glass ○​ 120°C for 30-60 mins under high pressure ​ Used pipettes or test tubes use a specialised glass waste ​ Ultraviolet Radiation container ○​ Wavelength range of 250-270 nm ​ If desired, empty bottles can be reused after triple rinsing ​ PPE should be worn as this range can cause with acetone, water, and again acetone burns on skins and eyes ○​ Effective against bacteria and viruses but not against spores BASIC BIOSAFETY ○​ Used to decontaminate air, water, and surfaces such Biosafety as in biological safety cabinets (BSCs) ​ Prevention of large-scale loss of biological integrity ​ Focus on both ecology and human health WASTE DISPOSAL ​ Protects against harmful incidents and keeps bacteria and ​ Hazardous waste (chemical, medical, or radioactive) is viruses contained generated in many laboratories and requires regulated ​ Important because thousands of labs around the world disposal to ensure safety of public health and the process infectious agents or create environments that environment allow infectious agents to exist ​ The regulation of hazardous waste handling must be enforced from the moment of generation until its disposal at an off-site final destination facility PH 156 | Laboratory Safety 5 of 9 Biosafety Levels WORKING ALONE IN THE LAB ​ Different labs have different biosafety levels, it gets stricter ​ Best practices and authorities say, “Don’t work alone” for higher-risk labs ​ Having a responsible partner in the lab minimizes the ○​ Biosafety Level 1 - works with the least dangerous danger you are in agents ○​ A responsible partner can see you and hear you, ○​ Biosafety Level 4 - require the strictest protocols knows how to respond in an emergency, use safety because infectious agents we handle post such a equipment and be able and willing to call an great risk emergency number ​ Regardless of level, understanding the basis of biosafety is ​ Do a risk assessment for all lab work and inform your lab absolutely imperative to protecting yourself and those partner around you ○​ Plan for emergencies ○​ Risk may not just come from the one you are doing Basic Biosafety Rules but also come from other projects within the lab ​ If you encounter problems in the lab, having a partner ​ Similar to standard lab safety helps keep the impact small. ​ No eating, drinking, adjusting contacts, applying cosmetics, wearing sandals, shorts or revealing clothes in labs PIPETTE SAFETY AND ERGONOMICS ​ First aid and spill kit required; immediate alert to biosafety ​ Long hours of pipetting can result in discomfort and have officer for exposure long term physical effects on your body Personal Protective Equipment (PPE) Set Up Bench to Avoid forward Leaning and Reaching ​ Clothing, gloves, googles, etc., ​ Setting laboratory bench properly helps alleviate ​ Protecting against injury or infection musculoskeletal discomfort and avoid injuries that can ​ Choice based on work, worn and stored only inside the develop overtime laboratory ○​ Repetitive forceful gripping combined with awkward ​ Proper training for employees using PPE postures can affect nerves, tendons, ligaments, joints, and spinal disc Microbes ​ Most laboratory have cutouts or open spaces under the work surface ​ Include bacteria and viruses that are too small to see ○​ Always try to work in one of these areas so you can ​ Pathogens can cause diseases stand or sit close to your bench ​ Safety measure: careful storage, transportation, use of ​ If you stand, consider the use of foot rails and floor mats to secondary containers, EPA-registered disinfectants, and reduce fatigue adherence to biosafety protocols ​ When sitting or standing by your workbench, make sure you can pipet at a comfortable height and reach (comfort Antimicrobial Agents zone) ​ Sterilants and disinfectants work differently ○​ Comfort Zone - extends between your waist and ​ Phenolics denature proteins; quaternary ammonia disrupts shoulders and includes the space between your body cell membranes and hand when you make a sweeping motion with ​ Efficacy affected by concentration, microbial population, your elbows by your sides and contact time ​ If you cannot adjust your bench height, consider using a chair that you can adjust Bleach and Disinfection ○​ Set the height of your chair so that the bench is at or ​ Bleach is effective against pathogens but can break down below elbow height lab materials ​ Use a foot ring or foot rest to support your feet then push ​ Differentiate between disinfection and sterilization your hips back so they are as far back as possible in the ​ Know lab requirements and use appropriate products chair Biological Safety Cabinets (BSC) Be Aware of your Posture while Working ​ Wash hands before and after using BSC ​ Your back should make good contact with the back of the ​ Do not store items in the cabinet chair ​ Disinfect work surfaces and items entering/exiting the BSC ○​ If you lean forward to reach the bench, adjust the ​ CDC and the American Biological Safety Association do angle of the back rest to provide back support not support UV lamps in BSC due to limited efficacy ○​ Supporting the middle part of your back is important if you do a lot of leaning and reaching. Fun Fact ​ If you have arm rest, adjust the height so your arms are ​ D value: Time required for a control agent to kill 90% of supported and your shoulders relaxed. Adjust to be just microorganisms under specified conditions. below your forearms ○​ Consider removing them if it cannot be adjusted and it Disinfectants and Sterilization interferes with work ​ Disinfection: Reducing microorganisms; not as complete ​ If you work in a fume hood or biosafety cabinet, adjust as sterilization your chair to work comfortably ​ Factors affecting efficacy: ○​ Sit stand chairs can help you by allowing you to sit ○​ Concentration closer with your hips and knees at an angle of about ○​ Microbial composition 60 rather than at right angles ○​ Contact time ○​ Adjust the sashes as much as possible to increase easy access into the hoods while assuring safety PH 156 | Laboratory Safety 6 of 9 ​ Placing regularly used items within a comfortable distance ​ Issues such as immersion depth and angle, cadence tip, from where you sit or stand to eliminate odd twists and position, and force can make a big difference in both turns that lead to muscle soreness, strains, and back accuracy and efficiency aches ​ Keep the pipette clean and in good repair, always match ○​ Pill up close to work materials, set up vials, tips, and the pipet to the task receptacles at heights and angles that are easy to ​ Consider specialty pipette such as a latch hook, magnetic reach multi-channel and electronic models when appropriate for ○​ Try to use shorter length pipettes, tips, tubes, and the task you must complete containers, whenever possible ○​ Use electronic or multi-channel pipette for repetitive ○​ Turntables, central waste receptacles, and platforms dispensing or when filling multi-well plates whenever can help workflow and reduce reach possible Select the Best Tool for the Job Limit Static and Repetitive Work by Rotating Tasks, Taking ​ Select the best pipet for the job to avoid several Breaks, and Moving Around musculoskeletal risks associated with pipetting ​ Rotate pipetting tasks with other co-workers or intersperse ○​ good match for the size and shape of your hand other tasks in your routine ○​ lightweight model that you can comfortably grasp ​ Try to limit continuous pipetting to 20 minutes ○​ Models slightly smaller than the diameter of your hand ​ If working for longer periods, take 3-5 minutes micro are easier to grip breaks every 20-30 minutes ​ Finger hooks are useful in resting your hand during the ○​ Try to utilize gentle hand arm and shoulder stretches pipet cycle during these breaks ○​ It can reduce tendon inflammation and nerve Summary compression and the risk of nerve injuries and ​ Be aware of your posture when working tendinitis ​ Set up bench to avoid forward leaning and reaching ​ Consider how hard it is to constantly insert tips ​ Limit static and repetitive work by rotating tasks, taking ○​ If a tip doesn’t seal properly, you will need to pound or breaks, and moving around even hand tighten it ​ Select the best tool for the job ○​ Keep the tip rack close to your body and don't use ​ Keep them in proper working order any more force than you need to load it ​ Removing the tip can be worse than loading it NOTE ○​ The ejection forces of a traditional pipet can place you ​ There are supplementary videos available in Canvas under at a high risk for injury especially if you pipet for long 'Laboratory Demonstrations' that we did not include to periods of time avoid redundancy. You can view these materials on your own time. ○​ Tip ejection forces, average 4 kg, studies recommend maximum force levels of about 2 kg ​ If your pipet requires high force, take lots of breaks to give REVIEW QUESTIONS your thumb a rest and reduce risk exposure 1.​ Which of the following best describes biosafety in a ​ Blowout force often exceeds tip ejection laboratory setting? ○​ The lateral pinch strength of females is about 7 kg and a.​ Preventing unauthorized access, theft, or misuse of about 10 kg for men biological agents ○​ Most people cannot work at their peak strength very b.​ Recognizing hazards, assessing risks, and selecting long without injury appropriate PPE ○​ Studies suggest that workers should stay under 30% c.​ Preventing unintentional exposure to biological agents or their inadvertent release of their maximum strength levels when working for d.​ Standardizing chemical hazard classification and prolonged periods communication ​ Newer pipet designs with reduced plunger 2.​ What is the primary purpose of the Globally activation and tip ejection forces make it possible Harmonized System (GHS) pictograms? to stay below high-risk force levels a.​ To ensure proper electrical safety in laboratories ​ When closing a pipet, notice where the controls b.​ To immediately communicate the type of chemical are located hazard present ​ Consider how far you have to extend your arm to c.​ To regulate laboratory dress codes and personal operate them protection ​ The further the thumb position from the palm, the d.​ To establish universal biosafety levels in research greater the strength required to pinch and press facilities controls ​ Control position, size, shape, and surface texture 3.​ Which of the following factors is the most common are all factors taken into account when choosing cause of laboratory-associated infections? a pipet a.​ Malfunctioning engineering controls ​ Volume adjustment controls are as important to consider b.​ Improperly stored biological agents as plunger controls c.​ Human factors, such as lack of training and improper ○​ Studies have shown that volume adjustment requires PPE use the highest level of muscle activity during pipetting d.​ Presence of genetically modified agents ○​ Ensure the volume adjustment dial is easy to grip and 4.​ According to the "Beaking" method, what is the first requires minimum revolutions to adjust the volume of step in removing a glove? proper pipetting techniques needed a.​ Pinch the middle of the glove upward. ​ Ask for formal training if you have never been trained in b.​ Form an L with your left hand and grab the cusp of the use of a pipet glove. c.​ Scoop under with the middle finger. PH 156 | Laboratory Safety 7 of 9  d.​ Wash hands with soap and water. 6. C. The risk assessment should evaluate risks using standard criteria, considering both likelihood and 5.​ In the incident described in the "PPE in the Biological consequences. While risks can be reduced, they cannot Lab" video, what combination of factors most be eliminated. After assessment, risks are classified as effectively prevented serious injury to the technician? acceptable or unacceptable. a.​ The technician's experience and the fire retardant properties of the lab coat. b.​ The technician's quick thinking and the availability of a REFERENCES nearby fire extinguisher. ​ Lectures c.​ The presence of a fire blanket and the technician's fire Dayrit, G. (2023). Biosafety in the Laboratory [Slides]. safety training. https://drive.google.com/file/d/1OpEQ-OYA0icj0KG6C5 d.​ The lab coat slowing the burn, and the technician's _PoVKSMYnIoaXs/view?pli=1 knowledge of fire extinguisher use. ​ Videos American Chemical Society. (2019). Working in the Lab 6.​ During the risk management process, after identifying Alone?...What IF... [Video]. Youtube. and evaluating risks, how should a laboratory prioritize https://www.youtube.com/watch?v=Y8DBd45W4hY Cornell University. (2014). PPE in the Biological Lab [Video]. those risks to determine if they are acceptable? Youtube. a.​ Focus primarily on risks with high likelihood, https://www.youtube.com/watch?v=OIzFCma1KHk regardless of their consequences. Dayrit, G. (2024). Biosafety in the lab [Video]. b.​ Only consider risks with high consequences, https://drive.google.com/file/d/1_4v5Zn9tEVDIQBQzau8 PIRjPbcfO4wED/view regardless of their likelihood. Dayrit, G. (2024). Waste Disposal [Video]. c.​ Compare each risk against a standard set of criteria, https://drive.google.com/file/d/1iAiXlcvaB9QlfM-KsWtR focusing on both the likelihood of the incident and the _0Bn0aEre3mr/view Kaufman, S. (2018). The "Beaking" Method [Video]. Youtube. severity of the consequences, to classify risks as https://www.youtube.com/watch?v=YfGivTv3wbc either acceptable or unacceptable. Quip Labs. (2019). Biosafety Basics Quip Laboratories [Video]. d.​ Eliminate all risks through immediate action, Youtube. regardless of feasibility or cost. https://www.youtube.com/watch?v=Wyjn4WpxS90&list =PL75iVCUt9zzoAJo-VdtBOZKnV7hbLQjnh 7.​ What is the most important/effective level of control in UCLA. (2009). Pipette Safety & Ergonomics Video [Video]. Youtube. the Hierarchy of Controls? https://www.youtube.com/watch?v=bqAsXMSs27s a.​ PPE ​ Website b.​ Substitution Canadian Centre for Occupational Health and Safety. (2024, May c.​ Elimination 10). CCOHS: WHMIS - Pictograms. https://www.ccohs.ca/oshanswers/chemicals/whmis_gh d.​ Engineering Controls s/pictograms.html 8.​ Which is not true about Dry Heat? Centers for Disease Control and Prevention. (n.d.). CDC LC Quick Learn: Recognize the Four Biosafety Levels. a.​ Disinfect glasswares Retrieved February 3, 2025, from b.​ 120°C for 30-60 mins under high pressure https://www.cdc.gov/training/quicklearns/biosafety/ c.​ 160-170°C for 2-4 hours Cornell University. (n.d.). 7. 4 routes of chemical entry | d.​ Not suitable for heat-labile materials environment, health and safety. Retrieved February 3, 2025, from 9.​ When should labels be affixed to chemical waste https://ehs.cornell.edu/research-safety/chemical-safety/ containers? laboratory-safety-manual/chapter-7-safe-chemical-use/ 74-routes a.​ When the container is full International Labor Organization. (2022, March). The Globally b.​ As soon as chemicals are added Harmonized System of Classification and Labelling of c.​ Just before disposal Chemicals (GHS). https://www.ilo.org/sites/default/files/wcmsp5/groups/p d.​ After a day ublic/@ed_dialogue/@lab_admin/documents/genericdoc 10.​ Which of the following practices should NOT be ument/wcms_841722.pdf National Research Council (US) Committee on Prudent Practices followed when working in a biological safety cabinet? in the Laboratory. (2011). The culture of laboratory a.​ Pipet tips and microcentrifuge tubes should be stored safety. In Prudent Practices in the Laboratory: Handling in the BSC. and Management of Chemical Hazards: Updated Version. National Academies Press (US). b.​ All equipment which goes into and comes out of the https://www.ncbi.nlm.nih.gov/books/NBK55882/ BSC should be disinfected. Tankeshwar, A. (2013, August 1). Biosafety levels and agents of c.​ The work surface of the BSC should be disinfected disease. Microbe Online. before and after work. https://microbeonline.com/primary-bio-safety-levels-an d-agents-of-disease/ d.​ Proper handwashing shall be observed before and World Health Organization. (2020). Laboratory Biosafety Manual after using the BSC. Fourth Edition. e.​ None of the above. https://umresearch.um.edu.my/wp-content/uploads/202 4/05/WHO-LABORATORY-BIOSAFETY-MANUAL-4th-ed ition.pdf ANSWER KEY 1.​ C. 6.​ C. 2.​ B. 7.​ C. 3.​ C. 8.​ B. 4.​ B. 9.​ B. 5.​ D. 10.​ A. Explanations 4. B. The "Beaking" method starts by forming an "L" with the left hand and using it to grab the cusp of the glove. 5. D. The lab coat, even though not fire-retardant, slowed the burn, and the technician's fire extinguisher training was crucial in preventing serious injury. PH 156 | Laboratory Safety 8 of 9  APPENDICES Figure 3. GHS pictograms. Figure 6. Relation of risk groups to biosafety levels, practices, and equipment (Tankeshwar, 2013). PH 156 | Laboratory Safety 9 of 9