Slide 1 Slide 1 Duration: 00:00:38 Advance mode: Auto Welcome to the Safe and Proper Laboratory Process section of Presentation One in the Reviewing Science course. To meet the objectives, the teacher must understand how to manage learning activities, tools, materials, equipment, and technologies to ensure the safety of all students. This presentation provides a general review of science lab processes, equipment, and safety. It is not appropriate for use as required safety training. Please consult your district for the most up-to-date safety training appropriate to your campus. Slide 2 Regulating Entities Duration: 00:00:36 The following entities set forth the requirements for the safety of each student in the science classroom. Teachers and staff should be aware of and follow the regulations set forth by the district. The Occupational Safety and Health Administration (OSHA) provides training requirements and guidelines at both the national and the state level, as determined by the state. Texas follows the Federal Plan. For more information, visit www.osha.gov.
Slide 3 Safe and Proper Laboratory Process Duration: 00:01:44 Safety in the science classroom and laboratory setting is a key responsibility of a science educator. The following includes information on how to identify, evaluate, prevent, and respond to potential hazards in the science classroom. The key to a safe science classroom or lab is to provide proper training with regular updates for staff and students participating in the science laboratory environment. Training should include how to identify and evaluate potential hazards, prevent hazards, and respond to hazards. All employees have a right to know about potential hazards and exposure to hazards. All employees must be informed about potentially toxic chemicals. An inventory list must be maintained and made available upon request. The inventory must include hazard information and the properties of the chemicals. Training must be provided for the safe handling and interpretation of the Safety Data Sheet (SDS). Proper labeling of chemical and hazardous materials is required, including chemical name, concentration, target organ, effects, preparation data, physical and health hazards, and the name and address of manufacturer. Safety training should include the use of a fire extinguisher, chemical fume hood, and protective equipment, such as gloves and goggles; chemical handling and hygiene; understanding the SDS; proper chemical disposal; and first aid. Safety Data Sheets (SDS) should be present in all laboratories for every chemical in the laboratory.
Slide 4 Slide 4 Duration: 00:01:22 Advance mode: Auto Slide 5 Slide 5 Duration: 00:01:42 Advance mode: Auto The Safety Data Sheet, or SDS, contains 16 sections. Section 1 contains all of the information on the chemical product and company identification. Section 2 of the SDS provides the composition of the substance, such as sodium chloride or, table salt. Section 3 lists the potential hazards of the substance, including whether it is toxic if inhaled or ingested, along with information on the flammability, reactivity, exposure and storage of the substance. Section 4 contains first aid measures. It explains what measure to take if the substance is inhaled or ingested, or comes in contact with eyes or skin. Section 5 provides fire fighting measures and the potential effects of heating the substance. Section 6 contains the information in case of an accidental release. Section 7 lists the information for the proper storage and handling of the substance. Section 8 details exposure controls and personal protections precautions. For example, whether goggles or an apron should be worn while working with the substance. Section 9 of the SDS contains the physical and chemical properties of the substance, such as molecular formula, molecular weight, and other information, including the boiling and melting point of the substance. Section 10 provides the substance s stability and reactivity. For example, if it reacts violently with water or other substances, it is a strong oxidizer or an acid. Toxicology information is located in section 11 and tells whether the substance has acute or chronic effects, and any organs that need to be of concern while handling the substance. Section 12 provides information on possible environmental effects. Proper disposal of the substance can be found in section 13. Section 14 lists any transport regulations placed on the substance. Section 15 is the regulatory section and provides any other regulatory information, and Section 16 contains any additional important information about the substances that is not captured within the other sections. The SDS provides all of the information necessary for the proper use, handling, and disposal of chemical substances used in the science classroom or laboratory. All students and staff should be properly trained
on how to read and locate the SDS. Slide 6 Required in all science labs Duration: 00:00:57 The following items are required in all science labs for the safety of staff and students. Students are usually introduced to formal science labs in upper elementary. The fire blanket must be visible and accessible. Ground Fault Circuit Interrupters (GFCIs) must be placed within 2 feet of water supplies. The shower and eye wash must be capable of continuous water flow. Eye protection must be available to all students. Sanitization for eye protection must also be available. Emergency exhaust fans must provide ventilation to the outside of the building. Master shut-off switches for gas, electrical, and compressed air with permanent handles must be clearly labeled. An ABC fire extinguisher should be visible, and exit signs should be properly and clearly labeled. All flammable materials must be stored in a fire-resistant storage cabinet.
Slide 7 Recommended for all science labs Duration: 00:00:49 A chemical spill kit should be available for the proper clean up of accidental chemical spills. Flame-retardant protective aprons are recommended. Fume hoods with spark-proof motors are recommended. Proper labeling of potentially hazardous chemicals, flammable and corrosive substances, waste containers, and broken glass is suggested. Proper labeling of potentially hazardous conditions is suggested. Slide 8 Chemical Safety Duration: 00:01:39 Teachers are responsible for providing a safe environment for all students with regard to chemical safety. This includes proper supervision, incorporation of safety procedures in science curriculum, a well-managed classroom, and student training on the proper use and handling of gradelevel appropriate chemical substances. When handling chemicals, only prepare laboratory solutions as directed by the lab manual, avoid contamination, clean glassware with distilled water before and after use, and provide the proper protective gear when working with glassware (e.g., safety goggles). Do not store chemicals on benches or near heat sources. Store only in secure, dry areas, based on reactivity. Acids should be stored and locked in a separate area from non-acids. All containers in the lab, especially possible carcinogens, MUST be properly labeled and stored to contain leaks and spills. Dispose of solutions based on local city or county disposal procedures. Chemical waste should be disposed of in properly labeled containers and separated based on chemical reactivity. The following substances are possible carcinogens and are never allowed in schools: Arsenic compounds
Benzene Benzidine Asbestos Acryonitriel Cadmium compounds Chloroform Chromium compounds Ethylene oxide Nickel powder Orthotoluidine Mercury Lead Formaldehyde Slide 9 Biological Safety Duration: 00:01:58 Teachers are responsible for providing a safe environment for all students with regard to biological safety as well. This includes proper supervision, incorporation of safety procedures in science curriculum, a well-managed classroom, and student training on the proper use and handling of gradelevel appropriate biological materials. Biological materials should never be stored near food or drinks and should always be appropriately labeled. Blood and body fluids should be placed in a well-secured container that has a secure lid to prevent leaking. All biological waste should be disposed of in biological hazardous waste bags. Animals should be obtained only from a known source to avoid pathogens and/or parasites. Always rinse specimens before handling. Provide and require students and staff to wear gloves while handling specimens. Teachers should model ethical care and treatment of animals. If students do not wish to participate in dissections for moral reasons, an alternative assignment must be provided without penalty. Live mammal and bird dissections are prohibited by law. Biological experimentation can be performed on all animals except mammals and birds by law. Physiological harm to any animal is prohibited. All animals must be handled in a safe and humane manner. Animals are not to remain on school property for extended vacations where adequate care cannot be provided. Staff can be
suspended or dismissed if not in compliance. Slide 10 Tools of Science Duration: 00:02:41 A variety of instruments are used in the science laboratory for measurements and observations. Below are some of the tools commonly used in elementary and/or secondary science labs. Click on each one to learn more. Balances, including electronic balances, triple beam balances, and the pan balance shown here, measure the mass of an object. Beakers are used for mixing, stirring, and heating liquid. Elementary students should use plastic beakers for safety reasons. Glassware is typically reserved for teacher or secondary student use. Bunsen burners or propane burners are used to heat substances in the high school laboratory. When using burners in the laboratory, students and staff members should take certain precautions. The shape of the Erlenmeyer flask allows for mixing by swirling without spilling. Elementary students use plastic flasks for safety reasons. Forceps are used to hold or grasp small objects. Funnels can be used to separate solid substances from liquids. Goggles protect the eyes from chemical and potential shattered glass exposure. Goggles should be worn at all times during laboratory investigations. Graduated cylinders are long, cylindrical tubes that are open at the top and sealed at the bottom. Graduated cylinders use calibrated volumetric scales and are used in the volume measurement of liquids. Elementary students should use plastic graduated cylinders for safety reasons. Hot plates, which can be set to different temperatures, are used to heat substances. Only teachers should have access to this tool in an elementary setting. Light microscopes are commonly used in secondary science labs to view microscopic organisms. Pipettes are used to transfer liquids from one container to another. Test tubes are used in the laboratory for holding, mixing, or heating small quantities of solids or liquids. Elementary students should use plastic test tubes for safety reasons. Test tube holders allow test tubes to be held over a flame without burning
the skin. Test tube racks hold test tubes. Thermometers are used to take temperature measurements. Beaker tongs, shown here, are used to hold hot beakers and reduce the risk of burning the skin. Crucible tongs are used to hold hot crucibles and reduce the risk of burning the skin. These tools are typically only found in secondary science classrooms. Slide 11 Experimental Results: Accuracy and Precision Duration: 00:01:22 Accuracy is defined by how close experimental results are to the value of the quantity that is being measured. Precision is how often the experimental results or measurements can be reproduced if measured multiple times. Errors are experimental uncertainty resulting from problems during measurement. The experimenter may be unable to make the same measurement in the exact same way each time. Errors due to calculations and reading of instruments are not considered in error analysis. In the example, the target was hit all three times. The results are both accurate and precise. In the example, the target was missed, but the results were reproduced each time. The results are not accurate, but they are precise. In the example, the target is not hit and the results are not reproduced, so it is neither accurate nor precise. In order to be accurate, it is important to read instruments precisely and record the experimental data accurately. To increase accuracy and precision, consider lab table height, use of laptops, use of recording devices, and clear vs. colored lines on glassware.
Slide 12 Gathering, Organizing, Displaying, and Communicating Data Duration: 00:02:05 Graphing is an important skill for communicating data for analysis. Two graphs commonly used in science are line graphs and bar graphs. Line graphs contain an independent variable and a dependent variable. The dependent variable changes based on the independent variable. This type of graph represents a trend between data. For example, the graph below shows the fish population in Lake Travis at different temperatures. Temperature is the independent variable that exists regardless, and the fish population is the dependent variable since it changes with the change in temperature. Bar graphs use rectangular bars of different heights that are proportional to the values they represent. They are generally used for comparing categories. For example, in the bar graph shown, organisms are being compared based on the environment to which they are exposed. Charts such as a pie chart, also can be used to display data. A pie chart is divided into sections that display data in numerical proportions. Pie charts are often used to show percentages. The pie chart to the right shows the percentage of different items present in weekly garbage. Tables can be easily constructed to display experimental data visually. The following table displays the percent abundance for each group, along with the group's mass. Diagrams provide a visual representation of an object. Students are usually introduced to designing experiments and writing lab reports in the upper elementary grades. The written lab report usually includes an investigative question or purpose, hypothesis, material list, procedure, data, results, and conclusion. Students should also be familiar with arranging data into a presentation and presenting their information to the class.
Slide 13 Units of Measurement Duration: 00:02:14 Taking measurements is a critical skill in science. Most students in the United States are confronted with an unfamiliar measurement system when they first make scientific measurements. Students familiar with inches and cups at home have to adjust to centimeters and milliliters in science class. Most scientists use the metric system. In the metric system, the standard unit for length is the meter; mass is measured in kilograms; and the liters are used for the measurement of volume. The units of the metric system are based on powers of 10. The base units include the gram, meter, and liter. Example: How many liters are in 45 milliliters? 1 liter = 0.001 milliliters 45 ml x 1 L/1000 ml = 0.045 L The measurement system that you may be the most familiar with is the English system. In the English system, the measurement for length is the foot; weight is measured in pounds; and quarts are used for the measurement of volume. Unlike the metric system, larger units are not as easily divided into smaller units and require calculations. Example: How many inches are in 7.6 feet? 7.6 feet x 12 inches/foot = 91.2 inches Sometimes, it is necessary to convert units from the English system to the metric system and vice versa. The table below shows several common units that are converted between the two systems. Example: How many pounds are in 12.5 kilograms? 1 kilogram = 2.2 pounds 12.5 kg x 2.2 lbs/kg = 27.5 lbs
Slide 14 Slide 14 Duration: 00:00:31 Advance mode: Auto This concludes the Safe and Proper Laboratory Process section in Presentation One of the Reviewing Science Course. As a teacher of young students, you have an important role in teaching and modeling safe and proper procedures during science investigations. Before you begin teaching, remember to consult your district for the most up-to-date safety training appropriate to your campus. Please proceed to the Impact of Science presentation.