Lab Safety Guidelines PDF

1. Safety in Lab 1.1 Introduction Although lab work can be fun, one should be mindful of the hazards involved. This chapter aims to familiarize you with the risks of the lab so that you may most significantly prevent injuring yourself, avoid damaging costly equipment, and timely completion of your...

1. Safety in Lab 1.1 Introduction Although lab work can be fun, one should be mindful of the hazards involved. This chapter aims to familiarize you with the risks of the lab so that you may most significantly prevent injuring yourself, avoid damaging costly equipment, and timely completion of your work can be achieved. These labs provide an opportunity for hands-on experience to augment your coursework's knowledge base. One aspect of that practical knowledge is mastering safe laboratory working techniques. Safety matters regardless of your level of lab experience, new or seasoned. Teaching you how to prevent mishaps and what to react when they occur, comes first. Learning good habits now is lot simpler than having to undo negative ones later. 1.2 Personal protection safety rules There are plenty of ways you might maximize your lab time. Initially, one should get ready for the lab ahead of time. Go over the contents and consider the lab before you start working. Long-term injury and time can be saved by mentally planning your activities in the lab that day. Be alert to any general hazards as you work in the lab. It is obligatory to 1. wear safety goggles. 2. wear a lab coat that is closed in the front. 3. tie up long hair. 4. wear appropriate gloves when manipulating dangerous substances (see later) 1  5. wear closed shoes (no sandals, flipflops etc.) In the laboratory it is not allowed to 1. eat or drink (let alone smoke!) 2. wear inappropriate clothes (shawls, blouses or shirts with loose sleeves or from easily flammable fabrics) 3. wear headphones to listen to music (alarms!) 4. work without a colleague being in hearing distance. 5. wear contact lenses (safety goggles with optical lenses are made available at no cost to permanent staff) 6. bring to or take out chemical products from the building. Precautions : 1. be familiar with the task at hand. (if not: seek assistance!) 2. carefully read the directions 3. understand the chemistry. 4. carefully and calmly plan delicate manipulations. 5. think before acting. THINK → ASK → DO Make sure you know where is the next: telephone (and what are the emergency numbers!) safety door fire extinguisher and fire blanket sandbox (to extinguish burning metals) first aid box person to ask/alert in case of problems safety shower, eye washing station, gas mask and how to use it ! safety instruction poster 2 Recommendations - do not obstruct walkways and safety exits - work in a stable position - do not run in the lab - use clean and functional lab material - wash your hands before and after manipulations - label all recipients clearly and readably - run and clean the eye showers every month. - do not keep food in lab fridges containing chemicals Order and cleanliness 3  - keep your lab equipment clean and in good shape - clean used glassware - keep order in your lab - dispose regularly of your chemical waste This will allow to: avoid contaminations prevent accidents prevent bad smells from spreading limit the risk of ignition and fire create a pleasant work climate work efficiently Protective measures - read and respect the safety labels and instructions on chemical bottles. - wear your personal safety equipment (goggles, lab coats, gloves etc.) correctly and keep it in shape. - respect the safety directives. Announce all abnormalities, incidents or accidents to your supervisor and/or to a member of the safety committee Safety goggles Our two eyes cannot be replaced !! they can be hurt by: i. splashes of chemicals ii. vapours and dust particles 4  iii. glass splinters iv. laser beams v. work done by your colleagues It is forbidden to wear contact lenses in the lab! Lab coat must be made from fabrics (cotton) that are equipped to : - reject liquids - reject odors - protect underlying clothes - are not flammable Take off your lab coat if you go to seminar rooms, cafeterias etc! Protective shields Gloves Types of safety gloves water-soluble products ⇒ latex (yellow) or nitrile gloves (blue) 5  acids, bases, alcohols ⇒ vinyl (white) or nitrile gloves toxic or corrosive products, solvents ⇒ nitrile gloves manipulation of glassware ⇒ kevlar gloves (green) Remarks on gloves All gloves are available plain or powdered. Nitrile gloves are about twice as expensive as latex gloves. Lab gloves are for protection, and it should be removed gloves before using keyboards, telephones, door handles, banisters etc. because else you may spread contaminations! How to remove gloves? - peel off the first glove by grabbing it with the cuff. - wrap it up into a ball and put that into the other, still protected hand. - peel off the second glove, touching only its interior surface. - then, enclose the second glove in the first - immediately proceed to wash your hands 6 When to change gloves? - as soon as a glove is soiled, or it leaks - at the end of a manipulation (except for the new red gloves) - at least every work hour (except for the new red gloves) (because after some time gloves become porous) Hoods The primary purpose of the hoods is to protect your health and safety and that of your colleagues - for better ventilation of the hood , - lower the glass pane - close unused hoods Please turn off the ventilation in unused hoods (this saves a lot of energy, particularly in winter. However, leave at least always one hood per lab on low speed (also at night). 7 1.3 Guidelines for Chemical Safety Acids and Bases Working with any substance, even water, entails inherent dangers. Prior to doing your laboratory experiment, it is advisable to allocate some time to acquaint yourself with these potential hazards. Acids and bases are among the most frequently used reagents. Avoid combining acids and bases unless specifically instructed to do so. The combination of the two substances can generate a substantial amount of thermal energy and result in detrimental effects. It is essential to always dilute acids or bases by adding them to water. The addition of water to a concentrated acid can result in an explosion due to the release of heat, which 8 can disperse acid over an entire room. A straightforward technique to remember this is to "add acid to water as you should." Dissipating the heat safely is achieved by adding the acid or base to the bigger volume of water. In case of spills To neutralize acid spills, sodium bicarbonate should be used, followed by cleaning up the spill with a paper towel or sponge. Avoid use a potent alkaline substance, such as sodium hydroxide, for the purpose of neutralizing a potent acid such as hydrochloric acid. Sodium bicarbonate is a more effective and safer option for completing the task. Base spills should be neutralized using boric acid and subsequently wiped off with a paper towel or sponge. Avoid using acetic acid or sodium bicarbonate for cleaning a spill of a basic substance. The sodium bicarbonate will not effectively neutralize the spill, and the acetic acid may undergo a vigorous reaction with the base. In the event of an acid or base spill on your skin, promptly rinse thoroughly with water. Powerful alkaline substances chemically interact with the oils present on your skin, resulting in the formation of a layer that imparts a sensation similar to soap. Continue rinsing until the sensation has completely disappeared. Do not try to counteract a spill on your skin. It has the potential to exacerbate the injury. Mercury may be utilized in these laboratory experiments. Mercury is frequently present in thermometers and related equipment. If a mercury spill occurs, promptly clean it up using a commercial product such as Resisorb ™, Hg Aborb ™, or elemental sulphur. One can also buy mercury sponges that create an amalgam with liquid mercury, thereby capturing it on the sponge's surface. Mercury is highly volatile, and even little droplets can lead to substantial exposure. Ensure that you clean the area completely after a spill. The health effects of mercury are widely recognized, and it is advisable to minimize contact with the metal. Reagents and Hazardous Waste When receiving reagents, it is important to keep away from immediately introducing any substances into the original container. This has the potential to pollute your stock. Alternatively, transfer a tiny quantity into a beaker or a clean weigh dish. After adding a chemical to a container, instantly label it. Once the experiment is complete, properly discard any remaining chemical as chemical waste. Avoid carelessly disposing of the remaining 9 chemical by pouring it down the sink. This is a detrimental behavior that poses possible risks. The sinks' drains should not be used for conducting extracurricular chemical experiments. Your teacher can assist you with the proper and secure disposal of chemicals. Glassware o Inspect your glassware for any signs of cracks or fractures every time you use it. It is important to avoid using glassware that is broken. Glassware with sharp edges should undergo a process called fire-polishing. o When transporting elongated glassware, it is important to ensure that it remains in an upright position. o Any device capable of rotation, such as thermometers and pipettes, should be placed in suitable holders. o Lubrication should be applied when inserting glass tubing, thermometers, or other objects into rubber stoppers, corks, or when connecting rubber tubing to glass hose connectors. Careful from applying force to the glass and shield your hands with a glove. o Avoid placing hot glassware on surfaces that are cold or wet, since this might cause it to break due to variations in temperatures. Utilize wooden tongs for holding the glassware till it reaches a lower temperature. Equipment o Prior to the initial usage of an instrument, it is essential to notify the laboratory technician and provide training to the researcher on the correct use of the equipment. It is essential to thoroughly examine manuals and standard operating procedures. o Extra care should be taken when working with an exposed flame. It is important to ensure that hair and clothing are kept at a safe distance from the flame. o When handling an open flame, it is imperative to utilise wooden tongs. 10 o Always supervise an open flame. When a hob or an electrical heater is not being utilized, switch it off. o Avoid heating a sealed container. The accumulation of pressure can lead to the container's detonation. o The heating devices should not be manually manipulated. o It is imperative not to alter the temperature settings while using an oven or a muffle furnace. Notify laboratory technicians if necessary. o It is not recommended to use plastic gloves when operating an oven or a muffle furnace. o It is advisable to utilize tongs when working with elevated temperatures. o It is important to avoid putting equipment that has been washed with solvents in a drying oven since there is a potential risk of explosion. o It is important to ensure that sample containers and tongs do not come into contact with the oven wall. o An analytical balance should be stored nearby while it is not being used. o When using a calibrated analytical balance, it is crucial to verify that the air bubble is positioned precisely in the centre of the level indication. Adjust the balance using foot screws until the air bubble of the water balance is positioned within the designated circle. o Avoid any accidental release of chemicals within the confined space of the balancing cage. In the event of a spill, promptly remove it using a brush. o Prior to utilizing the fume hood, it is important to activate the ventilation system. o It is necessary to conduct all operations at a minimum distance of 15 cm inside the fume hood. Additionally, it is important to keep the panel of the fume hood closed as frequently as feasible. 11  o Prior to operating in a hood with explosive or flammable chemicals, it is necessary to establish electrical connections for all apparatus. o It is important to ensure that the hands are thoroughly dry while handling an electrical device. o Avoid using devices whose correct usage is unknown. 1.4 Guidelines for Compressed Gas Safety There may arise situations where you will need to utilize compressed gases. Cylinders pose a significant hazard and, when compromised, exhibit projectile-like behavior. This hazard bears resemblance to a little CO2 cartridge capable of propelling a miniature rocket, albeit on a somewhat greater scale. A gas cylinder that is damaged has the ability to puncture cement walls. Always seek assistance from your instructor before attempting to relocate a cylinder. It is imperative to consistently secure cylinders with chains to prevent them from dropping and sustaining damage. 12 The regulator on a cylinder is equipped with fittings that are tailored to the particular gas being regulated. Do not alter a regulator in order to make it compatible with a cylinder. Several regulators are not compatible with gases other than those explicitly indicated. For instance, a regulator that has been previously employed with hydrogen must never be utilized with oxygen as it poses a significant risk of explosion. Over time, regulators utilized in conjunction with hydrogen may accumulate a layer of metal hydrides inside. When subjected to oxygen under pressure, they have the potential to undergo spontaneous explosion. Equivalent dangers arise when a compressed air regulator is employed on an oxygen tank. Oil that accumulates in the regulator from pressurized air can potentially cause an explosion when it comes into contact with oxygen. The safety provided by the various fittings is crucial in preventing mishaps. It is imperative not to disregard or surpass this safety margin. If you are using a compressed cylinder for the first time, it is advisable to seek assistance from your instructor. Here are the fundamental guidelines. Prior to using the regulator, check that the pressure- adjusting knob, located at the center of the regulator, is rotated in a counter-clockwise direction and is not tightened. Turn the cylinder valve until the pressure is displayed on the initial gauge of the regulator. To ensure your safety in the event of regulator failure, avoid standing directly in front of the regulator while performing this task. Rotate the pressure- adjusting knob in a clockwise direction to enable the passage of fluid through the regulator. The second gauge will quantify the pressure that is flowing through the regulator. The regulator can be equipped with a needle valve at the end to provide precise control over the flow. To deactivate a regulator, begin by shutting the valve on the cylinder. Subsequently, release the pressure in the regulator by venting the system. Ultimately, release the pressure- adjusting knob until it rotates without any resistance. 1.5 Guidelines for Biological Safety When handling water that may contain bacteria or specialized bacterial cultures, it is important to adhere to rigorous laboratory protocols. Approach all cultures as if they possess harmful microorganisms. After completing the experiment, it is important to thoroughly sanitize the area where you conducted your work using a solution of household bleach diluted at a ratio of 1:10. Additionally, commercial disinfectants might be utilized. 13 It is necessary to sterilize used petri dishes, pipettor tips, pipets, and other disposable devices that have been in touch with microorganisms before disposing of them. Inquire with your instructor about the designated location for disposing of biological waste before the sterilization process. Prior to disinfection, it is imperative to cleanse the area in which water contaminated with bacteria has been spilled. Additionally, it is necessary to properly dispose of the paper towels and gloves used in the cleaning process as biological waste. Regardless of using gloves, it is imperative to fully wash your hands before exiting the laboratory. Flaming is a necessary step in many biological procedures to sterilize loops and spreaders. This process involves immersing the tool in ethanol and subsequently incinerating the ethanol using a burner flame. Multiple dangers are present in this location. Ethanol is very combustible, hence extreme caution must be exercised while handling it in close proximity to an exposed flame. If you accidentally set fire to your ethanol, immediately smother the flame by placing a watch glass over it. Alternatively, you can extinguish the flame by using water. After sterilizing your loop, make sure to avoid touching the end that was exposed to the flame. The temperature will remain high, and you will also pollute your just cleansed circuit. 1.6 Guidelines for Electrical Safety Laboratory workstations include electronic devices, as do virtually all other types of workplaces. By outlining proper procedures for handling electrical equipment, lab safety regulations help reduce the likelihood of electric shocks and other injuries cau sed by improper use of these tools. i. Always consult your lab supervisor before operating any equipment that requires a high amperage current or voltage over 50V rms ac and 50V dc. ii. Under no circumstances may high voltage equipment be altered or modified. iii. Before adding a high voltage power source, make sure to switch it off. iv. Adjusting equipment that uses high voltage requires the use of only one hand. To be on the safe side, put your free hand in a pocket or behind your back. v. Ensure that all electrical panels are free from obstructions and can be easily accessed. 14  vi. Stay away from extension cords if at all possible. 1.7 Guidelines for Laser Safety While not as widely used as other lab safety regulations mentioned, lasers are utilized in many laboratories, necessitating adherence to essential guidelines to avoid harm. Specifically, staff may not consider the potential for lab safety mishaps caused by reflection. Establishing a concise and explicit set of safety regulations is crucial in order to guarantee that all individuals are fully informed about potential risks associated with laser usage and that they consistently wear the necessary personal protective gear. 1. Regardless of your confidence in the safety or low power of a laser beam, it is imperative that you never direct your gaze into it. 2. It is imperative to consistently use the suitable eyewear in sections of the laboratory where lasers are present. The predominant laser injuries occur when laser light scatters and reflects off the glossy surface of optical tables, the edges of mirrors, or mountings. Utilize laser curtains and signage. Wearing goggles that are specifically designed to withstand the laser's power and frequency will protect you from any harm caused by the scattered light. 3. It is imperative to avoid aligning your head with the laser beam. 4. Maintain the laser beam at or below the level of the chest at all times. 5. The dispersion of laser beams within the laboratory should be strictly prohibited. It is imperative to consistently employ beam stops to intercept laser beams. 6. Avoid crossing laser beams. 1.8 First aid Quickly remove individuals who suffered injuries from the hazardous area while focusing your own well-being. The subsequent measures are provided as initial emergency options until the arrival of medical aid. - Eye injuries by corrosives substances 15  Rinse the eyes thoroughly with a significant quantity of water (using eye showers or a douche) for approximately 10 minutes. Keep the eyelid in an open position with the fingers. - Skin chemical burns Dispose of contaminated clothing immediately. Cleanse the injured body parts thoroughly by utilizing the emergency showers located in the laboratory. - Burns Apply cold water to the burned area for approximately 10 minutes. Avoid the application of cream or oil. - Toxic gas inhalation Terminate the origin of the hazardous gas while ensuring your personal safety. Evacuate the wounded from the hazardous area. - Eye injuries with foreign parts Do not administer first aid, wait for a trained professional. - Opened wounds, bites, scrapes Apply a sterile bandage to the affected area using a first aid kit. - Ingestion of chemical substances Flush the oral cavity extensively with water, avoiding administering any antiemetics. - Hemorrhages To control the bleeding, elevate the injured limb, apply pressure with your finger or hand to stop the bleeding, and then cover the wound with a sterile bandage. A first aid kit. - Fractures 16  Provide reassurance to the individual and avoid any movement of the fractured limb. - Electrocutions Deactivate the electrical power by switching off the fuse, which is situated in the corridors. If respiratory arrest occurs, initiate artificial ventilation until help arrives. - Breathing stops Rapidly administer artificial respiration using a pocket mask or protective sheet if performing mouth-to-mouth breathing assistance. - Faintness, convulsions, unconsciousness Place the individual gently in the recovery position. Shield the head with clothes or protective coverings. 1.9 Safety Data Sheets Material Safety Data Sheets (MSDS) provide detailed information about the potential hazards and safety precautions associated with a particular material or substance. A significant number of chemical compounds utilized in laboratory experiments pose a risk to human health. Understanding the characteristics of these substances is crucial for both health considerations and for deciding appropriate first aid procedures following any workplace accidents. Prior to utilizing any chemical, it is imperative to thoroughly review the Material Safety Data Sheet (MSDS) and carry out experimental procedures under suitable conditions. Each chemical's MSDS should include details such as : a) Chemical name; b) Manufacturer's contact details; 17  c) Information on hazardous ingredients or identity; d) Physical and chemical properties ; e) Data about the hazards of fire and explosion; f) Data regarding the hazards to health; g) Measures must be taken for first assistance h) Handling and storage Note: The chemicals’ safety data sheets can be accessed online at http://www.sigmaaldrich.com/safety-center.html. Every individual should be granted the opportunity to obtain MSDS for every chemical they utilize. An Internationally Recognized System for the Naming and Classification of Chemicals Globally Harmonized System of Classification and Labelling of Chemicals, or GHS for short, is a UN-managed standard that aims to standardize the classification and labelling of hazardous materials from the many different systems that were in use before. A lot of back-and-forth between governments and businesses over the years led to this. What does the GHS stand for ? Chemical hazard communication elements and hazard classification criteria are harmonized globally through the GHS. An internationally recognized system for the naming and classification of chemicals that is managed by the United Nations. The GHS is more of a framework or set of guidelines for the classification and labelling of dangerous substances than a rule. Classification under the GHS aims to improve environmental and human health protection by providing consumers of chemicals with standardized information. Many nations have established procedures to govern the categorization and warning of chemicals. Despite their superficial similarities, the systems are different, which can cause confusion and discrepancies when it comes to how a product is classified, labelled, and even covered by Safety Data Sheets (SDS). Simplifying laws and improving worker 18 safety when it comes to chemical dangers is possible through moving to one standard in this era of global trade. Why was MSDS changed to SDS ? SDS stands for "Safety Data Sheet" and replaces MSDS. Around the world, people have been switching from MSDS to SDS since the turn of the millennium. Regardless of the name, Material Safety Data Sheets (MSDS) and Safety Data Sheets (SDS) all serve the same purpose: to detail the hazards associated with using a product or chemical in the workplace. If you require additional information on the product or what to do in the event of exposure or a spill, you can find it in the MSDS and SDS. Where do MSDSs and SDSs differ ? Chemical product property information was originally provided via MSDS. The revised system that complies with GHS regulations is known as SDS. Neither as standardized nor as universally acknowledged as SDS, MSDS was an inferior standard. How Are Material Safety Data Sheets (MSDS) and SDS Differed ? The information and language on the documents have changed since MSDS became SDS. In the SDS, what were formerly labelled "controlled products" on the MSDS are now referred to as "hazardous products." Classifying products, producing labels, publishing SDSs, and providing these labels with products for sale are all still responsibilities of the suppliers. SDS single words: WARNING: indicating a less severe risk DANGER: which denotes a more significant threat In contrast to MSDSs, SDSs now incorporate signal terms, such as: The following are some of the warning symbols that may appear on the label of a specific chemical: 19 20 21