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Do this now…. Go to http:// tinyurl.com/SAFETY-ACTIVATOR and complete the pre-lesson survey. Go to my eBoard and set up your Quia account with the “ Quia Instructions” note under the Electronics 1 tab.
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Do this now… • Go to http://tinyurl.com/SAFETY-ACTIVATORand complete the pre-lesson survey. • Go to my eBoard and set up your Quia account with the “Quia Instructions” note under the Electronics 1 tab. • I will give you your username and password to enter onto the website on a 3x5” index card. • You must use this information. • Your email address is: studentIDfirstname.lastname@example.org • Show your blank desktop and help the people in your row when you’re done.
Safety is an attitude. • The inside of human body is built to move electricity. • What does your nervous system do? • Our skin keeps us safe from low voltage shock, up to 40 volts. • Think of voltage as electrical potential energy. • Electrical current kills. • Current is the flow or movement of electricity.
Electrical Shock • Electrical shock occurs when an electric current flows through the body when a complete circuit exists.
Electrical Shock • Different levels of current produce the following results: • 0.001 AmpereA mild tingling sensation that can be felt. • 0.010 AmpereStart to lose muscular control. • 0.030 AmpereBreathing becomes upset and labored. • 0.100 AmpereDeath if the current lasts for more than a second • 0.200 AmpereSevere burns, breathing stops. Death.
Factors that influence the effects of electric shock: • Intensity of the current. • Frequency of the current. • Current path through the body. • Length of time current passes through the body. • High moisture in the room and on your body. Remember, it is the amount of current flow through the body, not the amount of voltage contacted that determines the severity of a shock.
General Safety Precautions • Remove power from the circuit or equipment prior to working with it • Remove and replace fuses only after the power to the circuit has been de-energized. • Make sure all equipment is properly grounded. • Use extreme caution when removing or installing batteries containing acid.
General Safety Precautions • Use cleaning fluids only in well-ventilated spaces. • Dispose of cleaning rags and other flammable materials in tightly closed metal containers. • In case of an electrical fire, de-energize the circuit and report it immediately to the appropriate authority.
Electrostatic Discharge (ESD) • Static electricity is an electrical charge at rest on a surface. • Electrostatic discharge takes place when the charged body comes near or touches a neutral surface. • A surface can become charged through three means: • Friction, rubbing two dissimilar surfaces together. • Induction, transferring a charge from your body to a board wrapped in plastic for someone else to handle. • Capacitance, changing the relative voltage of an integrated circuit by changing the surface it rests on.
Preventing ESD • Treat all electronic components and circuits as static sensitive. • Do not touch the leads, pins, or components of printed circuit board traces. • Before handling a component or circuit, discharge yourself by touching a grounded metal circuit. • Keep components in original packing materials until needed. • Never slide static components over any surface.
Personal Safety Precautions • Work only in clean, dry areas. • Do not wear loose or flapping clothing. • Wear only nonconductive shoes. • Remove all rings, wristwatches, bracelets, ID chains, and similar metal items.
Personal Safety Precautions • Do not use bare hands to remove hot parts. • Use a shorting stick to remove high-voltage charges on capacitors. • Make certain that the equipment being used is properly grounded with polarized plugs. • Remove power to a circuit prior to connecting alligator clips.
Hand Tools • Always use the proper tool for the job, right type and size. • When carrying tools, always keep the cutting edge down. • Keep hands clean when using tools. Avoid grease, dirt, or oil on hands when using any tool. • Clamp small pieces when using a hacksaw, screwdriver, or soldering iron. • Keep metal rules clear of electrical circuits. • Disconnect all electrical devices by pulling directly on the plug, never the cord. • Cut one wire at a time to avoid damaging the cutting tool. • NEVER USE A TOOL WITHOUT A RUBBER HANDLE
Power ToolsJust reading this slide does not qualify you to operate a machine! You must have individual training with the instructor. • Only the operator starts or stops a machine. When stopping a machine, wait until it comes to a complete stop before leaving the machine. • Make all adjustments to the machine prior to turning it on. • Never have any loose hand tools, rags, or brushes in the work area when applying power. • Keep all safety guards in their proper position at all times.
Power ToolsJust reading this slide does not qualify you to operate a machine! You must have individual training with the instructor. • Never force a cutting or drilling tool into a work-piece. • Only one person in the work zone at all times power is applied. • Have instructor check any special setups prior to applying power. • Use only grounded power tools with three-prong plugs or UL-approved housing power tools.