ECE Lab Safety. Module All Jan 2018

Transcription

1 ECE Lab Safety Module All Jan 2018

2 Agenda Lab Policies Electrical Safety Distribution Grounding Physiology CPR/AED Biological Safety Jewelry Lead Eye Safety Test online, 25 random multiple choice questions, 80% to pass

3 General Policies Be familiar with the specific hazards of your workspace. All class/lab doors shall remain closed and locked at all times In case of emergencies while on campus, dial (from campus phone) or (from cell phone). Transportation devices (bikes, skateboards, etc.) shall remain outdoors and locked to the appropriate rack Backpacks to be placed under desks - aisles shall remain clear Faculty are full-time monitors of safety, but safety is a shared responsibility by all All lab policies shall be followed Do not disturb others when they are working

4 General Policies Faulty equipment shall be reported to the appropriate authority. Repairs shall only be performed by authorized personnel. Seek assistance before when operating unfamiliar instruments, after you read the manual. You may only use equipment for which you have completed proper training. No one shall be operating equipment or working in a lab without another person present. All injuries must be reported using an Accident Report Form located in the wall folder in the lab. After appropriate medical attention is received, return the completed form to the technologist. Power cords shall not cross egress paths

5 CoE Laboratory Policies Closed toe shoes and long pants/skirts shall be worn in all labs Gloves shall be removed before exiting labs Eye protection shall be worn in all labs Know what you are measuring and expected value. If a faculty/staff member asks you to leave a laboratory for violation of any safety or laboratory policy, you must oblige immediately or you will be removed by public safety. Be professional our laboratories house some of the most advanced instruments available today. It is your lab and mostly your responsibility to keep them clean, safe, and functional.

6 CoE Laboratory Policies Our technologists treat all students in a friendly and professional manner; however, they are not your friends. They are professionals working in a professional setting - and they are to be treated with utmost respect, just like you would treat a faculty member or the dean. Any disrespectful treatment of our technologists will be considered as serious as disrespecting any faculty member, or the dean, and hence will not be tolerated. Technologists are to be addressed and respected in a manner that is commensurate with the professional nature of the work they are doing. They should be addressed as Mr. Leone or Mr. Meyers, and not by their first name. Any form of verbal or physical harassment will be handled directly and immediately by public safety.

7 ECE Laboratory Policies Do not access ceiling level services Chemicals (wet or dry), and all wet items are prohibited in all ECE labs unless approved by the ECE Technologist Food and drink are prohibited in all labs at all times All personnel shall wash their hands before entering a lab, and after the lab session and prior to consuming any food or drink. All ECE labs are RoHS compliant, the use of leaded solder is prohibited in labs unless approved by the ECE Technologist Jewelry is prohibited Always clean-up after yourself. Do not leave circuits / parts overnight. Whatever you leave there will be discarded!

8 ECE Laboratory Policies Do not leave soldering stations unattended; turn off when not being used. Keep solder tips clean. Do not operate soldering stations at high temperature setting for long periods of time. Turn off instruments when finished work. Use appropriate cabling. All students should have their own basic tools which include the following items: breadboards, pliers/cutters/strippers, screwdrivers, cables, and other items required for basic lab work. IEEE student branch sells kits, or you can buy them yourself. Lab PCs are to be used for undergraduate lab work only.

9 ECE Laboratory Policies You may only enter one of t he Centers or the technologists office area if granted access. You may only acquire items when they are given to you by one of the technologists or student workers. You may not take, borrow, or remove any item from the Resource Center, Metrology Lab, stock room, or Fab Center without permission.

10 Parts Ordering Policies The ECE Department supplies students with most electronic parts needed for undergraduate projects free of charge, regardless of discipline. Parts commonly used for classes are stocked in the lab parts bins, along with 24ga solid wire used for breadboard interconnects. We stock thousands of the most common parts in our stock room. Access to the stock room is limited to the technologists and their staff (student workers). If you need a part, please the technologists following the guidelines in the ECE Parts Ordering document listed below and your parts will be pulled and be ready for pick up during regular business hours.

11 Parts Ordering Policies If we do not have a part you need for a class related project, we will order it for you. You need to inform the technologists about your needs, along with the justification for the request. Department paid ordering of unnecessarily expensive, improperly specified, or unjustified components will be denied. If you wish to bypass their recommendations, you may pay for the components yourself. The technologists are instructed to inform the professor of poor engineering practices, such as ordering improperly specified parts, which may result in a reduced grade in your projects. For detailed ordering information please visit the ECE Resource Center website. Parts needed for graduate projects are provided under the project s grant. Please see your advisor for grand funding details. When ordering parts, please include the Fund and Organization numbers.

12 For Current to Flow Need a path AND a difference in voltage potentials for current to flow!

13 500,000 Volt Birds!!!

14 500,000 Volt Man!!!

15 Ohm s Law The Flow The Potential E = I*R I = E/R The Path

16 Skin Resistance Skin resistance protects the body from electricity The body has resistance to current flow More than 99% of the body's resistance to electric current flow is at the skin A calloused, dry hand may have more than 100,000 Ω because of a thick outer layer of dead cells in the stratum corneum The internal body resistance is about 300 Ω, being related to the wet, relatively salty tissues beneath the skin. Capacitive effect of skin Ways protective skin resistance can be greatly reduced: Significant physical skin damage: cuts, abrasions, burns Higher voltages (several hundred volts and above) Rapid application of voltage to an area of the skin Immersion in water

17 Skin Resistance

18 Skin Resistance

19 Average Current Levels Estimated effects of 60 Hz AC currents* 1 ma Barely perceptible 16 ma Maximum current an average man can grasp and let go 20 ma Paralysis of respiratory muscles 100 ma Ventricular fibrillation threshold 2 A Cardiac standstill and internal organ damage 15/20 A Common fuse breaker opens circuit *From NIOSH. Contact with 20 ma of current can be fatal. As a frame of reference, common household circuit breaker may be rated at 15, 20, or 30 A, and is attributable to the majority of fatal electrocutions..

20 Average Current Levels Log-log graph of the effect of alternating current I of duration T passing from left hand to feet as defined in IEC publication AC-1: imperceptible AC-2: perceptible but no muscle reaction AC-3: muscle contraction with reversible effects AC-4: possible irreversible effects AC-4.1: up to 5% probability of ventricular fibrillation AC-4.2: 5-50% probability of fibrillation AC-4.3: over 50% probability of fibrillation

21 Nervous System and Organs Current flowing through the thoracic cavity can be fatal Current flowing through just a limb (e.g. hand to elbow or foot to knee) is less problematic

22 Heart Operation Conduction System

23 Heart Operation System Timing

24 Heart Operation Polarization Timing

25 Heart Operation Polarization

26 Isolated Ground Chassis ground is connected to earth ground via a buried ground rod Chassis ground provides a alternate path to ground as a safety measure, real ground vs. neutral

27 The Path

28 GFCI/RCD Ground Fault Circuit Interrupter/Residual Current Device Shuts off power if an imbalance is detected between line and neutral conductors Trip current = 5 ma +-1 ma, well below the let-go threshold Under ideal conditions the current through the safety ground is zero

29 High Voltage Dangers High voltage potentials can result in: Rapid breakdown of the skin s dielectric (insulative) capabilities Non-linear increase in (higher) current flow Non-contact shock due to ionization of the air (plasma arc) Electroporation Electrolysis

30 High Voltage Electrical Burn

31 High Voltage Electrical Burn

32 High Voltage Electrical Burn

33 480 VAC 3-Phase Arc Flash embed videos

34 One-Handed Measurements Clip reference lead to the circuit, use one hand to take reading, other hand NOT TOUCHING circuit, chassis, ground or any other conductive surface (e.g. put your free hand in your pocket)

35 Hands-only Cardio Resuscitation

36 Hands-only Cardio Resuscitation IN 2005

37 Hands-only Cardio Resuscitation Your only job is to keep blood flowing to the brain!

38 Helping an Electrocution Victim Scene safety Priority #1 First thing You don t want to become victim number two Turn off power Confirm the victim is in cardiac arrest Shout, shake, pinch In parallel Call 911 (on campus ) Start compressions Retrieve AED Follow AED prompts

39 Hands-only Cardio Resuscitation

40 Heart Operation Blood Flow

41 Automatic External Defibrillator An AED can reset the heart It needs a shockable condition (V-fib) It cannot restart a heart (asystole condition)

42 Degloving

43 Degloving

44 Affects of Lead Poisoning ADHD Irritability Poor attention span Muscular tremor Loss of memory Decreased libido Impotence Birth defects Depression/mood changes Headache Diminished hand dexterity Diminished reaction time Dizziness Fatigue Increased nervousness Lethargy Malaise Paresthesia Diminished cognitive performance Reduced IQ scores Weakness Diminished postural balance Diminished peripheral nerve function Diminished visual motor performance High blood pressure Heart attack Renal failure

45 Good Hygiene Washing hands before lab Removes oils from skin Oils, hand lotions, and grease from foods lowers skin resistance Washing removes and increases skin resistance when dry Reduces shock hazard Removes germs Prevents contamination and spread of germs Keeps equipment clean Washing hands after lab Removes lead Removes contaminants (fluxes, oxides, organic compounds, etc.)

46 Exploding Parts

47 Exploding Parts

48 Solder Splashing

49 Flying Objects

50 IF IT ISN T SAFE, SAY SO!!! - Dr. Schmalzel

51 Questions?