Name: airflow controls for safer lab workspaces
Uploaded: 2023-04-30T06:57:00.000Z
Duration: 5 min 48 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.

Fume Hoods and Laminar Flow Cabinets

1. 油烟罩
<ol><li>使用<ol>
<li>当材料产生有害的蒸气、烟雾或空气颗粒, 如细二氧化硅粉或挥发性致癌物 (如苯) 时, 使用油烟罩。</li>
	</ol>
</li>
	<li>操作<ol>
<li>空气被吸引, 虽然打开脸的遮光罩, 在那里的用户工作, 并通过排气。不断向内流动的空气, 以防止危险的蒸气, 烟雾, 和微粒从逃生通过引擎盖开放, 使用户和其他实验室工作人员的安全。</li>
	</ol>
</li>
	<li>面部流速必须足够高, 以使引擎盖有效。低流速可以使有害的烟雾、蒸气或微粒通过打开引擎盖向用户逃生。一个低流速的原因是有可调整的窗口在敞篷开头, 被称为窗扇, 太高。油烟罩具有低流速报警和窗扇高度报警是常见的。典型的流速是在0.41 和0.51 米/秒之间 (ANSI/AIHA/ASSE Z9.5)。抽油烟机应有明确标明的窗扇的最大安全工作高度。</li>
	<li>有几个安全使用油烟罩的规则。<ol>
<li>永远不要把头放在引擎盖上, 因为把头插在引擎盖里会暴露出有害的物质。引擎盖的设计是为了保护用户在使用时不受化学物质的照射。只有使用者的手臂应该存在于引擎盖中。在任何时候都要穿戴适当的个人防护装备 (PPE), 而不管油烟机所提供的保护。如果未知, 请咨询组织的环境健康 &amp; 安全 (EHS) 办公室, 以了解适当的 PPE 建议。</li>
		<li>始终与窗扇在或低于最大安全高度。</li>
		<li>不使用时, 窗扇应关闭。关闭窗扇, 确保了一个更安全的工作环境, 为所有实验室住户。此外, 与不适当的油烟罩操作相关的能源成本是巨大的。保持窗扇的高度在最低, 非工作日的水平是更高的能效。</li>
		<li>不要使用引擎盖进行化学贮存。在适当的地点储存化学品, 如易燃的柜子, 并在需要时将其带入油烟罩。</li>
		<li>将所有材料放在油烟罩中至少6英寸远离油烟罩面的边缘。当工作是在6英寸的边缘进行, 蒸气, 烟雾, 和颗粒更有可能逃脱。</li>
		<li>正如良好的管家原则适用于工作实验室的长凳, 同样的原则应在油烟罩内实行。</li>
	</ol>
</li>
	<li>对通风柜进行定期保养, 确保其安全运行。维修应包括测试报警和测试流速在设计操作窗扇位置。许多因素会影响水流速度, 包括引擎盖所在房间内的水流模式和排气口的障碍物。如果在设计操作窗扇位置的流速较低, 请将窗扇向下, 直到流速达到所需速度。许多现代油烟罩都有空气流速监测器, 实时监测流速。如果窗扇变得太低, 在油烟罩上进行有效的工作, 停止操作, 直到问题的根源解决。</li>
	<li>油烟罩变化<ol>
<li>有许多类型的更专门的油烟罩, 可能会遇到。这些包括高氯酸罩, 放射性同位素罩, 无罩, 和其他。更多可以阅读关于这些在 ANSI/AIHA/ASSE Z9.5 的要求。</li>
	</ol>
</li>
</ol>2. 层流柜
<ol><li>使用<ol>
<li>当需要清洁的环境, 没有微粒或生物污染物时, 使用层流柜。常见的例子包括使用组织培养或半导体晶片。层流柜防止空气污染进入机柜工作空间。空气中的层流 (与湍流相反) 最大限度地减少了箱体内样品的交叉污染。</li>
	</ol>
</li>
	<li>空气被过滤器过滤, 并吹过工作空间, 向用户。不断向外流动的清洁空气保持一个未污染的工作空间。一些层流柜装有 UV C 灯, 以便在使用前对工作区进行消毒。</li>
	<li>层流柜有两种类型: 水平流和垂直流 (图 1)。水平流柜从机柜的背面向用户水平吹净空气, 而垂直流罩将清洁空气从机柜的天花板吹向工作区的地板, 然后将其击中底座并在水平方向上流动。向用户的方向。垂直的流动橱柜使用与窗扇拉下来。水平流柜没有窗扇。两种类型的层流柜都有其优缺点。</li>
</ol><img alt="Figure 1" src="/files/ftp_upload/10372/10372fig1v2.jpg"> 图 1.水平和垂直层流罩的图.
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always"><tbody>
<tr>
<td colspan="2">水平层流罩</td>
		</tr>
<tr>
<td>优势</td>
			<td>缺点</td>
		</tr>
<tr>
<td>手/手套污染较少, 因为他们通常是下风的项目在内阁</td>
			<td>气流在用户脸上吹</td>
		</tr>
<tr>
<td>减少气流紊流</td>
			<td>工作空间中的大型对象会阻碍清洁空气流动, 降低效率</td>
		</tr>
<tr>
<td colspan="2">立式层流罩</td>
		</tr>
<tr>
<td>优势</td>
			<td>缺点</td>
		</tr>
<tr>
<td>气流不会在用户脸上爆炸</td>
			<td>不能将手和手臂置于物体上方</td>
		</tr>
<tr>
<td>工作区中项目的交叉污染较少</td>
			<td>气流紊流增加</td>
		</tr>
</tbody></table>表1。水平和垂直层流罩的优缺点。
<ol start="4"><li>提示, 以确保有效使用层流柜。<ol>
<li>总是注意不要把项目下游的项目, 可能导致交叉污染。这在使用生物样品时尤其重要。</li>
		<li>尽量减少杂乱。柜中的物料越多, 可能发生的污染就越大。大项目会扰乱水流。</li>
		<li>确保在进入机柜前, 将手/手套和任何物品带入机柜时不受污染。</li>
		<li>所有项目必须放在6英寸或进一步从内阁开幕的边缘。在6英寸的边缘的空气更可能与外部空气混合, 这意味着6英寸以内的物体更容易受到污染。</li>
		<li>定期检修应在层流柜内进行, 以确保其安全运行。维护应包括检查和更换高效空气过滤器, 检查机柜是否有泄漏, 以及测试气流速度。通过测试通过过滤器的微粒的数量, 可以检查空气过滤器的完整性。过滤器应删除99.97% 或更大的0.3 µm 粒子。如果流速太低, 橱柜将无法有效地保持污染物。如果流速太大, 流动将是湍流, 污染变得更有可能。</li>
	</ol>
</li>
</ol>

烟罩和层流柜是实验室中的有用工具, 用于防止有害物质的危害, 并在使用敏感材料时保持清洁的工作空间。然而, 烟罩和层流柜只有在正确使用时才有效。遵循简单的操作准则, 定期进行维护, 油烟机和层流柜可以作为实验室的有效工具。

烟罩和层流柜

罗伯特 m. Rioux & 威廉 a. 艾略特, 宾夕法尼亚州立大学, 大学公园, 宾夕法尼亚州
通风罩和层流柜是在类似原理下运行的工程控制装置。两者都使用恒定的气流来防止实验室环境及其居民受到污染。油烟罩防止有害物质退出引擎盖工作区, 而层流柜则防止污染物进入机柜工作空间。
通风系统是为了尽量减少对有害气体、烟雾和微粒的接触而设计的。空气的恒定流动被画入敞篷开头, 限制蒸气、烟雾和微粒的逃命, 然后被拉扯通过排气。层流柜被用来维持一个无菌/清洁的环境由不断流动的高效率微粒 arrestance (高效空气过滤) 的气体向外, 最大限度地减少污染空气进入内阁工作空间。经高效过滤的空气减少了有害化学物质或微粒进入实验室的机会。高效过滤器可去除99.97% 或更大的0.3 µm 粒子。

Robert M. Rioux & William A. Elliott，宾夕法尼亚州立大学，大学城，宾夕法尼亚州  
通风橱和层流柜属于工程控制措施……

通风橱和层流柜是实验室中防止危险情况和污染的关键设备。在通风橱和层流柜中，通过气流来减少危害或污染物。通风橱通过工作区域吸入空气，以去除有害气体和细小颗粒；而层流柜则将空气经滤器过滤后吹出，防止灰尘或生物材料对样品造成污染。本视频将演示通风橱和层流柜的工作原理、使用方法以及如何进行维护。通风橱和层流柜利用层流空气运行，这种气流以平行的流线进行，互不交叉。与湍流不同，层流能够通过绕过物体并清除有害颗粒，防止样品之间的交叉污染。通风橱主要有三个部分：带窗扇的开口面、工作区和排风系统。排风系统中的风扇通过开口面将空气吸入，经过工作区，再通过排风系统排出。这种气流进而将有害烟雾和颗粒从排风系统中抽出，并远离实验室环境。在适当高度时，通风柜的活动窗会限制开口尺寸，从而保持较高的气流速度。这种高气流对于防止烟雾逸出至关重要。与此同时，层流柜有两种类型：水平式和垂直式。在这两种类型中，空气通过进气口和净化过滤器被吸入，从而去除灰尘和细菌等微小颗粒。水平式生物安全柜使气流水平穿过工作区。这种类型的生物安全柜可减少手部和手套对样品的污染，因为操作者的手和手套位于样品的下风向。然而，气流会直接吹向使用者，且较大的物体可能阻碍气流。 在垂直式通风柜中，气流从上方被引导至工作区表面，然后从窗扇旁排出。由于这种气流会直接接触工作区材料的表面，因此有助于防止交叉污染。然而，窗扇可能会限制手部操作，且气流的湍流程度较水平式通风柜更高。现在，我们将向您展示如何在实验室环境中使用这些工作区，以及如何进行基本的维护。为了安全使用通风橱，务必穿戴适当的个人防护装备。将窗扇升起的高度不得超过标示的最大安全工作高度，以确保通风橱内有足够的气流通过。为防止接触有害气体或颗粒，操作时仅将手臂伸入通风橱内，切勿将头部伸入工作区域。此外，为确保通风橱内各处风速充足，应保持工作区域整洁有序，并将所有物品移至距通风橱正面至少六英寸以外的位置。在通风橱内工作完成后，应取出所有物品。切勿在通风橱内存放化学品，而应将其存放在指定的储存区域，例如易燃品专用柜。最后，请关闭通风橱的窗板，以确保更安全的实验室环境并减少能源消耗。在通风柜门处于最大开启高度时，通过测试报警装置和气流速度进行定期维护。如果风速过低，请降低视窗，直至达到所需速度。如果视窗过低导致无法在通风柜内进行操作，请停止工作，直至问题根源得到解决。层流柜通常用于需要防止污染的场所，例如生物实验室，因此您需要注意自身及实验室空气可能带来的污染。为防止污染，在使用层流柜或打开前窗之前，应使用乙醇对手套和所有设备进行消毒。确保窗扇高度不超过允许的最大高度，以保证足够的气流。保持操作柜内整洁，避免杂乱，并确保物品放置位置距离边缘至少6英寸，因为该区域最易受到实验室空气的污染。此外，应避免将物品上下游依次放置而造成交叉污染的风险。操作完成后，移除工作区内的所有物品以防止杂乱，并关闭前窗以防止污染。如果生物安全柜配备有紫外-C灯，则打开紫外灯以对工作区进行消毒。对层流柜进行定期维护。通过在纱网边缘等敏感区域涂抹肥皂溶液来检查是否存在泄漏，若有空气逸出，溶液会在泄漏处产生气泡。您刚刚观看了 JoVE 关于通风橱和层流柜的简介视频。现在您应该了解它们的工作原理、使用方法以及如何进行维护。感谢观看！

Education

教育

JoVE Science Education

Basic Biology

基础生物学

Lab Safety

实验室安全

airflow controls for safer lab workspaces

Fume hoods and laminar flow cabinets are airflow controls used in laboratories. They both rely on a constant stream of air to protect the lab environment and the people in it. These systems work in similar ways, but they serve different purposes.

A fume hood is a ventilation system that helps reduce exposure to hazardous vapors, fumes, and particles. Air is drawn into the hood opening, which helps keep harmful substances inside the workspace. The air is then pulled out through the exhaust.

A laminar flow cabinet is used to keep a workspace clean and sterile. It sends HEPA-filtered air outward to lower the chance that contaminated air enters the cabinet. HEPA stands for high-efficiency particulate arrestance, and this type of filter removes 99.97% or more of 0.3 μm particles.

Airflow Controls for Safer Lab Workspaces

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emergency eyewash and shower stations

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electrical safety

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Centrifuges are used to separate heterogeneous mixtures by spinning particles in a fluid at high speed. The motion creates a force away from the axis of rotation. Heavier particles move faster toward the bottom of the sample holder, and the rate depends on particle size and density. This process is called centrifugation, and it speeds up sedimentation, which is the settling of particles out of a liquid. Gravity can separate some mixtures on its own, but that can take a long time.

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

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chemical storage: categories, hazards and compatibilities

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Safe Chemical Labels and Storage Basics

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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...

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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

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Autoclaving lab materials safely is an important part of decontamination in the laboratory. This method is commonly used for items that have contacted biological samples, especially those that may contain microorganisms. An autoclave cleans materials with pressurized steam at a high temperature. The steam and heat work together to kill microorganisms on the loaded items. For this reason, effective autoclaving depends on good steam flow and strong heat transfer. Packaging matters because it...

fume hoods and laminar flow cabinets

Fume hoods and laminar flow cabinets are airflow controls used in laboratories. They both rely on a constant stream of air to protect the lab environment and the people in it. These systems work in similar ways, but they serve different purposes. A fume hood is a ventilation system that helps reduce exposure to hazardous vapors, fumes, and particles. Air is drawn into the hood opening, which helps keep harmful substances inside the workspace. The air is then pulled out through the exhaust. A...

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

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Vacuum Pumps for Laboratory Procedures

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operating the glovebox

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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

Laboratory cleaning methods are a key part of biosafety because microbial contamination can build up and spread disease. Decontamination is used to reduce that risk on lab surfaces and equipment. The level of cleaning depends on how much contamination is present and what kind of item needs treatment. Decontamination can be grouped into disinfection and sterilization. Disinfection removes pathogenic microorganisms, but it does not remove bacterial spores on lab surfaces or equipment.

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

本系列提供了使用危险材料和设备时应遵循的安全指导原则。它涵盖了个人防护装备，电气安全和一般应急指南等普遍主题，以及化学和生物实验室的一些特定安全程序。

Learn how fume hoods and laminar flow cabinets use airflow in labs. Compare how they protect people, materials, and clean workspaces.

Airflow Controls for Safer Lab Workspaces | JoVE K12

Chemistry

CHEM.1

CHEM.1.C

Chemistry and Physics

IPC.1

IPC.1.C

Robert Rioux

Overview

Mechanism of fume hoods and laminar flow cabinets

Use and Maintenance of Fume Hoods

Use and maintenance of laminar flow cabinets

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 ...

Electrical Safety

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

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 ...

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
The ability to repeat an experiment and get the same results, or reproducibility, is essential in scientific research. However, ...

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
Record keeping is a vital skill in science and organic chemistry labs. Without proper notes, descriptions, quantities, or ...

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:

Airflow Controls for Safer Lab Workspaces

Description

Transcript

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