cianbro - basic electrical awareness

A BASIC GUIDE FOR ALL CIANBRO PROJECTS

2012

1

Electrical Awareness in Construction

Operations

Purpose of Discussion2

ELECTRICITY

1. What is it and the dangers working near it.

2. General rules for equipment operators and other team members to protect self and others.

3. What to do in emergency situations. (Equipment Contact)

IMPORTANT POINT3

This presentation provides general knowledge only. No one viewing this

presentation will become an electrically qualified person

Common Myths4

Question #1: You have to make contact with a power line to sustain an injury?

Common Myths5

MYTH #1: ANSWER

Question #1: You have to make contact with a power line to sustain an injury?

False: Electricity can arc or jump from its source to another object. (Equipment, person, ground)

Common Myths6

Question#2: Most utility lines are non-electric and can’t hurt me.

Common Myths7

MYTH #2: ANSWER

Question#2: Most utility lines are non-electric and can’t hurt me.

False: Because most folks, including construction workers, can’t tell the difference and don’t know whether a line is energized or not, “NO LINE IS SAFE TO TOUCH-EVER “ !!

Common Myths8

Question#3: Any object contacting a power line will automatically kill or de-energize the line.

Common Myths9

MYTH #3: ANSWER

Question#3: Any object contacting a power line will automatically kill or de-energize the line.

False: A fault will not always de-energize the line. (faulty devices, protective equipment etc.)

Electricity Is Charged Particles

Electricity Is Charged Particles

Electricity Electricity

• Will take many paths as it goes to ground.

• Doesn’t care how it gets there.

• A common distribution line contains thousands of molecules expressed in electical terms as voltage and amps.

10

What is Electricity?

Invisible

Travels At The Speed Of Light

It Doesn’t Take Many AMPs To Hurt or Kill11

1000 miliamps = 1 AMP

60 mA is not enough current to light a light bulb !!

General Rules To Protect Self & Others(Is Electricity Present?)

12

Site inspection. (IS POWER PRESENT OVERHEAD OR UNDERGROUND?)

Does the Daily Activity Plan identify where the hazards are and what needs to happen to work safely in this environment?

Is there a qualified person providing guidance and direction?

Overhead Utilities (What’s On That Distribution Utility

Pole?)13

Underground UtilitiesCall Before You Dig (811 International

#)14

When You Ignore Dig Safe15

General Rules To Protect Self & Others(Operating Equipment)

16

Line Clearance Distance is the zone from the nearest energized conductor out. This distance is based on voltage of line. A minimum of 20 feet is required, however, actual line clearance will be provided by qualified person.

General Rules To Protect Self & Others(Operating Equipment)

17

If equipment plus extended load enters the line clearance zone, an activity plan with spotter is required.

Elevated and colored non-conductive tag lines warning operator and spotter must be in place.

Also, if all lift work is taking place in the opposite direction away from the line, (to the right side of this picture) as long as the potential reach of equipment or extended load falls into the line clearance zone (20 feet minimum) activity plan, spotter etc. are required.

Does My Work Plan Account For The Tools And Activities I’m About To Engage

In ??18

Dealing With Emergency Situations(Power Line Contact)

19

What You Need To Know About Touch Potential!

Dealing With Emergency Situations(Power Line Contact)

20

By touching the truck you become a path to ground.

REMEMBER: You do not know if the line is energized. STAY AWAY!!

Dealing With Emergency Situations(Power Line Contact)

21

What You Need To Know About Step Potential

Electricity can and does energize the area around a piece of equipment. A person stepping (lifting their feet) from a high to low area of potential can make themselves a path to ground causing injury or death.

Dealing With Emergency Situations

(Power Line Contact)22

Electrical contact and you are on or in the equipment:

• Operator SHOULD STAY ON OR INSIDE piece of equipment.

• Warn others that contact has occurred and for others to STAY AWAY.

• Attempt to break contact and call 911.• IF YOU NEED TO LEAVE MACHINE (e.g.

equipment fire etc.) operator should with feet together jump clear of equipment and shuffle feet in small steps away from area. ) THIS LAST ACTION SHOULD BE TAKEN ONLY IF NO OTHER OPTIONS EXIST.

Dealing With Emergency Situations(Power Line Contact)

23

Electrical contact and you are on the ground near machine:

• STAY where you are and DON'T MOVE. (unless machine is on fire then leave area by shuffling feet in small steps.)

• DO NOT TOUCH the machine or anything connected with the machine.

• WARN OTHERS that an electrical strike has occurred and to stay away.

Note: if you are outside the work area DO NOT approach equipment or people to help.

What To Do If Contact Occurs24

Dealing With Emergency Situations(Power Line Contact)

25

An operator (or worker) who must leave the equipment or equipment area should jump clear, landing with both feet together while maintaining balance. The driver must then shuffle away using very short steps. Too large a step could put each foot in a different voltage zone and electrocute the driver.

Quote26

“Habits are safer than rules; you don’t have to watch them. And you don’t have

to keep them either. They keep you.”

Frank Crane