Even Low Voltages Can Kill! Severity of shock depends on: Current flowing through body Duration of current flow through body Path of current through body Ex: Hand contact w/ 120V (hand-to-hand pathway) I = 120V / 2000 ohms = 0.06 amperes = 60 mA (w/ wet hands, resistance is decreased)
Effects of Electrical Current Reference: Lawrence Livermore National Laboratory-- Document HS5220-W
Identifying Hazards: Outlets, Facility Wiring Avoid overloading electrical outlets Ensure to guard from exposed wiring or energized parts Label all circuit-breaker switches Leave at least 36” clearance in front of electrical panels Ensure proper use of extension cords NEVER repair/ modify facility electrical wiring Contact a qualified licensed electrician to perform work.
Identifying Hazards: Laboratory Equipment n Inspect tools/ equipment before use n Protective measures: 3-prong plugs Double insulation on handheld tools GFCI-type outlets n For any tools/ appliances that generate heat (soldering irons, hot plates, etc.), unplug when not in use
Research Apparatus/ Systems: Design Safety n Incorporate into the design: Protective devices Proper grounding Proper equipment enclosures Warning signs and labels n Systems safety design should be reviewed and approved by a qualified professional.
Research Apparatus/ Systems: Working with Electrical Systems Only knowledgeable and qualified persons shall work on electrical circuits/systems BASIC RULES: Properly de-energize systems before starting work (should include lockout and tag) Never work alone Resist “hurry-up” pressures Know local emergency procedures
Research Apparatus/ Systems: High Hazard Operations Personnel involved in a high hazard operation must use safe work procedures (a written safety procedure is required,SOP*). High hazard operations include, but are not limited to work involving: Energized circuits Higher voltage systems (> 240 V) Capacitors (>10 J stored at > 50V) (*Standard Operating Procedure)
Response to Electrical Shock Protect yourself Call 9-911 Warn others of hazard Shut off power immediately Move victim to safety if safe to do so Give necessary first aid IF TRAINED Notify supervisor
Electrical Fire Don’t use water or touch burning objects If possible, unplug or turn off power Activate fire alarm and call 9-911 If small fire and within your ability, use CO2 or ABC fire extinguisher to put out. Ensure that personnel have taken fire extinguisher training from EH&S-- Fire Safety Program (723- 0609)
Basic Electrical Safety Tips n Understand the hazards of your task. n Understand the equipment and circuit functions. n Make sure that you are trained to perform the task. n Don’t be afraid to ask for help.
Remember Even low voltages will kill Electricity does not discriminate-- Even the most experienced are at risk! For more information, contact EH&S– Occupational Health & Safety Program: 725-3209 lsteng@forsythe Stanford Fire Marshal’s Office 723-0609 email@example.com