Name: electrical safety
Uploaded: 2023-04-30T06:56:27.000Z
Duration: 4 min 53 s
Channel: JoVE

K12 Standards

Texas Essential Knowledge and Skills

High School

Specialised Topic in Science

112.51.c.1.

112.51.c.1.C.

Electrical Safety

1. Preparation for Electrical Hazards
<ol>
	<li>Be familiar with the location of the laboratory electric control panel and know how to shut down the power in case of emergency. Locate the circuit breaker box in the laboratory and identify the circuit in which the electrified equipment is plugged into. All circuit breakers should be labeled appropriately, identifying the laboratory area or specific equipment it is associated with.</li>
	<li>Be familiar with the type and location(s) of fire extinguishers in case of an electrical fire. Electrical fires (also known as Class C fires) require an extinguisher containing carbon dioxide. The location of the fire extinguisher should be marked overhead or with floor signage with arrows pointing to the location. According to OSHA, the 4 key steps for proper use of an extinguisher are3: 
	a. Pull the pin. 
	b. Aim the nozzle towards the base of the fire. 
	c. Squeeze the trigger to control the release of agent. 
	d. Sweep from side to side.</li>
	<li>Inspect all laboratory electrical equipment periodically to ensure that all equipment and its associated internal and peripheral wires are in prime working conditions. If any wires are in poor condition, have them repaired or replaced by a qualified electrician. It may be advantageous to have group members assigned to this task with the results of their investigation provided in a log book associated with the instrument.</li>
</ol>
2. Avoiding Electric Shock
<ol>
	<li>Never touch electronics with wet hands or wet materials.</li>
	<li>Check that all power cords are in good condition before turning power on. Frayed cords or exposed wires should not be used. Have the cord repaired or replaced by a qualified electrician.</li>
	<li>Keep wires away from corrosive chemicals and organic solvents to avoid erosion of insulation on wires.</li>
	<li>Replace damaged or broken sockets, plugs, and joints immediately to avoid further damage. Do not attempt to force a plug into a socket into which it does not fit.</li>
	<li>Shut down the power and unplug the power cord before opening the cover to any electrical devices. Be aware that some capacitors may still be charged up even hours after removing the cover.</li>
	<li>Only use equipment with grounding plugs in the lab. The main plugs used for lab equipment include single-phase with safety ground, three-phase with safety ground, single-phase center tapped with safety ground, and three-phase with neutral with safety ground. Do not ever force a plug into a socket. Verify that they are appropriate mates.</li>
	<li>Never use extension cords for permanent lab equipment except for personal computers or temporary usage. Use surge protectors to protect electrical devices from voltage spikes. Avoid &#34;daisy chaining&#34; of extension cords.</li>
	<li>Never take the risk of repairing unknown electrical issues. Ask qualified electrical workers to inspect or repair any unknown electrical issues.</li>
	<li>Never touch a person being electrically shocked because you will act as a conduit for the electricity to reach ground. Call 911 immediately. Ensure your safety first and then shut down the power if possible or use non-conductive material such as wood, glass, or rubber to pull the person away from the electric contact.</li>
</ol>
3. Avoiding Electrical Fire or Explosion
<ol>
	<li>Don&#39;t overload a circuit. If a circuit is overloaded, the actual power, current, and voltage might exceed the rated value and lead to a fire. If you are unable to determine the rated values, consult with a person who can determine if the current circuit load exceeds the maximum recommended draws.</li>
	<li>Store flammable and explosive chemicals away from electric devices. The sparks generated by electric devices might cause fire or an explosion with flammable and explosive chemicals nearby.</li>
	<li>Make sure all electric devices are away from hot point sources (i.e., an open flame) to prevent melting and electrical fire.</li>
	<li>In case of electrical fire, first leave the area and call 911 immediately. Pull the most convenient fire alarm and shut down the main power source if safe and possible. Never use water or a conductive foam extinguisher. Use sand or a carbon dioxide extinguisher instead.</li>
</ol>

Electrical devices are everywhere in the laboratory. It is essential to follow electrical safety principles to prevent electrical shock, electrical fire, or explosion. Be prepared about what steps should be taken in the case of emergency. Identify and mark the location of fire extinguishers in the laboratory. Be sure to use an extinguisher meant for a Class C fire. Always remember to get to personal safety first and then shut down the power to any malfunctioning electrical devices if it can be done in a safe manner.

electrical safety

Robert M. Rioux &amp; Suprita Jharimune, Pennsylvania State University, University Park, PA
Among the many hazards present in the laboratory, electrical hazards are one of the most common we must be cognizant of since most of the laboratory equipment we use requires electricity for operation. Improper handling or operation of electrical devices might lead to electric shock with the potential risk of injury or even death. Electric sparks can lead to fire or explosion (since many flammable chemicals may be stored nearby to electrified instrumentation). Therefore, knowledge regarding electrical safety and what to do in case of emergency is essential for the laboratory personnel. Precautions can be employed when working in the laboratory to avoid electric shock and electrical fire or explosion.

Robert M. Rioux &amp; Suprita Jharimune, Pennsylvania State University, University Park, PA
Among the many hazards present in the laboratory, electrical ...

Safe handling of electrical equipment is as important as the handling of chemical materials, however, the hazardous nature of electrical devices is often overlooked.Improper operation of electrically-powered devices may potentially lead to injury or death by electric shock. Additionally, electrical sparks in the laboratory may lead to fire or explosions, especially when highly flammable or potentially explosive chemicals are placed in close proximity.Prevention of electrical accidents involves inspection of electrical wiring, keeping power cords at distances safe from water or chemicals, and situational awareness.This video will illustrate the necessary precautions to take before using electrically-powered devices, and the procedures used to prevent or handle shock-related accidents and electrical fires.Before powering up any electrical device, make sure the power cord is in good condition. Do not use the device with a frayed cord or exposed wires.Make sure the device is on a sturdy surface free from clutter or debris to prevent it from falling. Additionally, keep flammable and corrosive chemicals at a safe distance from electrical outlets.Familiarize yourself with the emergency electrical shut off and the circuit breaker box in the event that a device needs to be shut down. Properly label the circuits to which each electrical outlet is connected.Inspect all laboratory electrical equipment on a regular basis by checking for the wiring conditions. In case of damaged wire or defective device have the parts replaced by experienced personnel immediately.To prevent electrical shock, keep plugged-in devices away from any water-filled sinks or tubs, and avoid touching them with wet hands.Additionally, use only electrically-powered devices equipped with a grounding plug. Avoid forcing a plug into an ill-fitting socket, and replace any damaged sockets or plugs.Always use surge protectors to protect electrical devices from voltage spikes, and never use extension cords for permanent laboratory equipment.Electrical fires may be caused by contact with flammable chemicals, but also by overloaded circuits. Use no more than two electrical devices per outlet, or use surge protectors to prevent overload. Additionally, keep electrical devices away from open flames to avoid melting of the wire.Always know the location of the fire extinguisher. In case of a small electrical fire, use a CO2 extinguisher or sand.If a fire extinguisher needs to be used follow the PASS rule. Pull the pin first. Then take the nozzle and aim towards the base of the fire and squeeze the trigger. Slowly sweep the nozzle from side to side to cover the burning area.In case of a large fire, sound the fire alarm, leave the area immediately, and call 911.If a lab worker has been electrically shocked, ensure that the power is off, and call 911. Do not touch the victim with bare skin to avoid acting as a conduit for the electricity to reach ground. Always use non-conductive materials such as wood, glass or rubber to help the electrically shocked person.You've just watched JoVE's introduction to electrical safety. You should now understand safeguards against electrical safety hazards, how to be prepared in the event of an accident, what to do to prevent an electric shock and electrical fires. Thanks for watching!

Education

JoVE Science Education

Basic Biology

Lab Safety

proper personal protective equipment

Choosing the Right Lab PPE

Choosing the right lab PPE is a key part of working safely in a laboratory. PPE, or personal protective equipment, helps reduce risk when hazards are present. Laboratory hazards can be many and varied. The right choice of PPE helps make the lab a safe place to work. Students should match their protective gear to the tasks and conditions in the lab. This topic focuses on selecting proper protection for the situation at hand. Wearing the correct PPE supports safer lab work and helps limit...

emergency eyewash and shower stations

Laboratory Chemical Spill Response Stations

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Preventing Lab Electric Shock and Fires

Electrical hazards are a common lab safety concern. Most laboratory equipment uses electricity to work, so students and lab staff must stay alert around cords, plugs, and powered devices. Improper use of electrical equipment can cause electric shock. In serious cases, this can lead to injury or death. Electrical sparks are also dangerous in the lab. They can start a fire or trigger an explosion. This risk matters because many flammable chemicals may be stored near powered instruments. Knowing...

working with centrifuges

Centrifuge Safety and Sample Separation

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working with hot and cold sources

Safe Use of Lab Heat and Cold Sources

Safe use of lab heat and cold sources is an important part of laboratory work. Extreme temperatures are common in many lab tasks. They can involve both high heat and very low temperatures. Bunsen burners and hot plates are widely used in research labs and industry. A Bunsen burner is a gas burner that gives a direct flame. A hot plate is an electric device that warms containers without an open flame. Because these tools reach high temperatures, users need to follow safe handling procedures. <br...

guidelines in case of a laboratory emergency

guidelines-in-case-of-a-laboratory-emergency

Lab Spill and Accident Response Basics

Lab spill and accident response basics help students stay safe during common laboratory emergencies. The most common lab emergencies include chemical spills, fire or explosion, electric shock, and personnel injuries. Many accidents happen because of poor planning or lack of attention, so prevention is always the first step. Good lab safety starts before an emergency happens. Students should wear proper personal protective equipment, or PPE, in the laboratory. Regular lab inspection and...

chemical storage: categories, hazards and compatibilities

chemical-storage-categories-hazards-and-compatibilities

Safe Chemical Labels and Storage Basics

Safe chemical storage and labeling help prevent dangerous reactions in school and research labs. Chemicals can vary widely in their properties and reactivity, so they must be managed, stored, and labeled correctly as part of an Environmental, Health and Safety (EHS) program. If chemicals are not handled properly, they can create harmful or even destructive results. These risks include toxic fume production, fire, explosion, human fatality, property damage, and environmental hazards. Proper...

safe handling of mineral acids

Mineral Acids in the Lab

Mineral acids are common chemicals in research laboratories, and they must be handled with care. These acids, also called inorganic acids, are water-soluble acids formed from inorganic minerals by chemical reaction. Their corrosive nature makes them a major safety risk in the lab. Examples of mineral acids include boric acid, chromic acid, hydrochloric acid, hydrofluoric acid, nitric acid, perchloric acid, phosphoric acid, and sulfuric acid. These acids are important reagents in research, and...

handling chemical spills

Chemical Spill Safety in the Lab

Chemical spill safety in the lab is essential whenever hazardous chemicals are used. Spills can happen at any time during laboratory work. Even a small spill can become dangerous if people are not prepared to respond quickly and correctly. Preparing for a chemical spill helps protect public health and the environment. Lab teams need to know how to respond to accidental releases of hazardous chemicals before an emergency happens. Safe cleanup also depends on proper disposal of the spilled...

proper use of autoclaves

Autoclaving Lab Materials Safely

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fume hoods and laminar flow cabinets

Airflow Controls for Safer Lab Workspaces

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handling air- and water-sensitive chemicals using a schlenk line

handling-air-and-water-sensitive-chemicals-using-a-schlenk-line

Schlenk Line Setup for Inert Atmospheres

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proper operation of vacuum based equipment

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Vacuum Pumps for Laboratory Procedures

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operating the glovebox

Glovebox Atmosphere and Sample Transfer

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operation of high-pressure reactor vessels

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Safe Use of Pressure Vessels in Chemistry

High-pressure reactor vessels are used in synthetic chemistry to handle gases safely during reactions. They help chemists carry out gas-based processes such as hydrogenation, oxidation, and amination. These reactions often use hydrogen, oxygen, or ammonia, which are important reagents in the lab. These gases usually dissolve poorly in standard reaction mixtures. Because of that, high pressure is needed to make the reaction proceed at a useful rate. The vessel creates a sealed space that keeps...

decontamination for laboratory biosafety

Lab Cleaning Methods for Biosafety

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proper waste disposal

Lab Waste Management and Safety

Lab waste management and safety are essential parts of any laboratory activity. Waste generated during work must be handled correctly from the moment it is created until it reaches its final offsite disposal facility. Poor waste disposal can seriously harm public health and the environment. A waste management system should be planned before any lab work begins. This system guides how waste is collected, stored, and prepared for removal. For hazardous waste, special rules apply because its...

lab safety

This collection provides safety guidelines to be followed when working with hazardous materials and equipment. It covers universal topics such as PPE, electrical safety, and general emergency guidelines, as well as some specific safety procedures for chemistry and biology laboratories.

Learn how electrical hazards in the lab can cause shock, fire, or explosion, and why safe handling of powered equipment matters for high school labs.

Preventing Lab Electric Shock and Fires | JoVE K12

Chemistry

CHEM.1

CHEM.1.C

Biology

BIO.1

BIO.1.C

Physics

PHYS.1

PHYS.1.C

Chemistry and Physics

IPC.1

IPC.1.C

Robert Rioux

Suprita Jharimune

Pennsylvania State University

Overview

Before Powering Up

Avoiding Electrical Shock

In Case of an Emergency

Summary

The Scientific Method

The scientific method is a detailed, empirical problem-solving process used by biologists and other scientists. This iterative approach involves ...

Inductive Reasoning

Inductive reasoning is a form of logical thinking that uses related observations to arrive at a general conclusion. It is uncertain and operates in ...

Deductive Reasoning

Deductive reasoning, or deduction, is the type of logic used in hypothesis-based science. In deductive reasoning, the pattern of thinking moves in the ...

Correlation and Causation

Correlation and CausationStatistical tests can calculate whether there is a relationship, or correlation, between independent and dependent variables. A ...

Ask questions and define problems related to specialized topics of study based on observations or information from text, phenomena, models, or investigations;

112.51.c.1.A.

Scientific Method

The scientific method is used to solve problems and explain phenomena. The development of the scientific method coincided with changes in philosophy ...

Demonstrating the Scientific Method with Tree Branches
ExpandObtain branches containing a few dozen typical leaves from five different local tree species. ...

Observation and Background Research
ExpandNOTE: The first two steps in the scientific process involve studying and observing natural phenomena of ...

Problem-Solving

A problem-solving strategy is a plan of action used to find a solution. It involves trial and error, algorithms, heuristics, and insights. Effective ...

Problem Definition

Problem definition is the initial and the most essential step in research.
The researcher identifies and explains the specific issue or gap to be ...

Apply science practices related to specialized topics of study to plan and conduct investigations or use engineering practices to design solutions to problems;

112.51.c.1.B.

Proper Personal Protective Equipment

Robert M. Rioux &#38; William A Elliott, Pennsylvania State University, University Park, PA
Hazards are many and varied in the laboratory, but the right ...

Emergency Eyewash and Shower Stations

Robert M. Rioux, Pennsylvania State University, University Park, PA
The Occupational Safety and Health Administration (OSHA) mandates that an emergency ...

Working with Centrifuges

Source: Robert M. Rioux &amp; Suprita Jharimune, Pennsylvania State University, University Park, PA
Earth's gravitational force is capable of separating ...

Working with Hot and Cold Sources

Source: Robert M. Rioux &amp; Suprita Jharimune, Pennsylvania State University, University Park, PA
Working with extreme temperatures, both high and low, ...

Guidelines in Case of a Laboratory Emergency

Robert M. Rioux &amp; Zhifeng Chen, Pennsylvania State University, University Park, PA
The most common laboratory emergencies include chemical spills, ...

Chemical Storage: Categories, Hazards And Compatibilities

Source: Robert M. Rioux &amp; Taslima A. Zaman, Pennsylvania State University, University Park, PA
While the use of various chemicals in experimental ...

Safe Handling of Mineral Acids

Source: Robert M. Rioux &#38; Taslima A. Zaman, Pennsylvania State University, University Park, PA
A mineral acid (or inorganic acid) is defined as a ...

Handling Chemical Spills

Source: Robert M. Rioux &#38; Taslima Zaman, Pennsylvania State University, University Park, PA
Since chemicals are commonly used for laboratory research ...

Proper Use of Autoclaves

Robert M. Rioux &amp; Zhifeng Chen, Pennsylvania State University, University Park, PA
Autoclaving is one of the most commonly used methods in the ...

Fume Hoods and Laminar Flow Cabinets

Robert M. Rioux &amp; William A. Elliott, Pennsylvania State University, University Park, PA
Fume hoods and laminar flow cabinets are engineering controls ...

Decontamination for Laboratory Biosafety

Robert M. Rioux and Zhifeng Chen, Pennsylvania State University, University Park, PA
Decontamination is essential for laboratory biosafety, as the ...

Proper Waste Disposal

Robert M. Rioux and Taslima A. Zaman, Pennsylvania State University, Pennsylvania, PA

Users are responsible for the proper disposal of the waste ...

Use appropriate safety equipment and practices during laboratory, classroom, and field investigations as outlined in Texas Education Agency-approved safety standards;

Common Lab Glassware and Uses

Source: Laboratory of Dr. Neal Abrams &#8212; SUNY College of Environmental Science and Forestry
Glassware is a regular appearance in the professional ...

Lab Techniques

Measurement Accuracy
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Source: Smaa Koraym at Johns Hopkins University, MD, USA

	Preparation of LaboratoryExpand
	Here we show the laboratory preparation for 10 students ...

Source: Smaa Koraym at Johns Hopkins University, MD, USA

	Determining the Density of an EggExpand
	Density is a measure of how compact a substance or ...

Proper Lab Notebook Keeping

Organic Lab Notebook Keeping
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Source: Lara Al Hariri at the University of Massachusetts Amherst, MA, USA

	Preparation of the LaboratoryExpand
	Here, we show the laboratory preparation ...

Source: Lara Al Hariri and Ahmed Basabrain at the University of Massachusetts Amherst, MA, USA

	Nitration of Methyl BenzoateExpand
	From this lab onward, ...

Use tools appropriate to the specialized topic of study;

112.51.c.1.D.

SI Units: 2019 Redefinition

Measurement is integral to analytical chemistry. Each record comprises a number &#8211; denoting the magnitude&#160; &#8211; and the unit &#8211; a ...

International System of Units

The International System of Units, known as the SI system, is a universally accepted measurement system recognized and used worldwide. The SI system is ...

Measurement: Standard Units

Every measurement provides three kinds of information: the size or magnitude of the measurement (a number), a standard of comparison for the measurement ...

Measurement: Derived Units

The International System of Units or SI system, by international agreement, has fixed measurement units for seven fundamental properties: length, mass, ...

Collect quantitative data using the International System of Units (SI) or qualitative data as evidence as appropriate to the specialized topic of study;

112.51.c.1.E.

Review and Preview

Data are individual items of information obtained from a population or sample. Data may be classified as qualitative (categorical), quantitative ...

What is a Frequency Distribution

A frequency is the number of times a value of the data occurs. The sum of all the frequency values represents the total number of students included in the ...

Cumulative Frequency Distribution

A cumulative frequency distribution is another type of frequency distribution. Instead of reporting how many data values fall in some classes, it reports ...

Ogive Graph

An ogive graph is sometimes called a cumulative frequency polygon. It is one type of frequency polygon that shows cumulative frequency. In other words, ...

Histogram

The histogram is a graphical representation in the x-y form of data distribution in a data set. The horizontal x-axis is labeled with what the data ...

Relative Frequency Histogram

The relative frequency depicts the proportion of data points that have each value. The frequency tells the number of data points that have each value. ...

Scatter Plot

The most common and easiest way to display the relationship between two variables, x and y, is a scatter plot. A scatter plot shows the direction of a ...

Time-Series Graph

A time-series graph is a line graph with repeated measurements taken at successive intervals of time. It is also called a time series chart. To construct ...

Bar Graph

A bar graph is also called a bar chart and consists of bars that are separated from each other. It either uses horizontal or vertical bars to show ...

Multiple Bar Graph

As the name suggests, a multiple bar graph is the same as a bar graph but has multiple bars to depict relationships between different data values. One can ...

Pareto Chart

A Pareto chart is a bar graph or a combination of both line and bar graphs. The bar lengths represent the individual values or the frequency, while the ...

Pie Chart

A pie chart (or a pie graph) is a circular graphical chart or a pictorial representation of categorical data. It is divided into slices of pie each ...

Organize quantitative or qualitative data using representations appropriate to the specialized topic of study such as scatter plots, line graphs, bar graphs, charts, data tables, diagrams, scientific drawings, and student-prepared models;

112.51.c.1.F.

Modeling and Similitude

A scaled model of a dam is tested in a controlled environment to observe how it will manage water flow, turbulence, and pressure.
This setup predicts the ...

Typical Model Studies

Typical model studies analyze scaled-down systems to predict fluid behavior, focusing on interactions with free surfaces and flow around immersed bodies.
...

design-example-creating-a-hydraulic-model-of-a-dam-spillway

Design Example: Creating a Hydraulic Model of a Dam Spillway

A hydraulic model of a dam spillway is often created by scaling down the design, typically to a 1:15 ratio, to replicate key flow characteristics such as ...

Models, Theories, and Laws

Scientists frequently use models to help them comprehend a specific collection of phenomena. In physics, a model is a condensed version of a physical ...

/files/media/science-education/science-education-thumbs/14686.jpg

Concepts and Prototypes

The human nervous system translates sensory stimuli into neural impulses, which the brain processes into information as thoughts and memories, forming ...

Develop and use models to represent phenomena, systems, processes, or solutions to problems as appropriate to the specialized topic of study; and

112.51.c.1.G.

Scientific and engineering practices. The student, for at least 40% of instructional time, asks questions, identifies problems, and plans and safely conducts classroom, laboratory, and field investigations to explain phenomena or design solutions using appropriate tools and models. The student is expected to:

Electrical Safety

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