Module 3
Download
1 / 19

Evaluating Electrical Risk Factors - PowerPoint PPT Presentation


  • 55 Views
  • Updated On :

Module 3. Evaluating Electrical Risk Factors. Evaluate. Recognize. Control. Module Objectives. Recognize the purpose and various methods for evaluating arc flash. Identify arc flash approach boundaries and their meaning. List the steps for conducting a task analysis. Module Objectives.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Evaluating Electrical Risk Factors' - ocean


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Slide1 l.jpg

Module 3

Evaluating Electrical Risk Factors


Slide2 l.jpg

Evaluate

Recognize

Control


Slide3 l.jpg

Module Objectives

  • Recognize the purpose and various methods for evaluating arc flash.

  • Identify arc flash approach boundaries and their meaning.

  • List the steps for conducting a task analysis.


Slide4 l.jpg

Module Objectives

  • Recognize how to conduct a fall hazard evaluation.

  • Given a case study, analyze the hazards and recommend improvements.


Slide5 l.jpg

Desired Outputs for Analyses

  • To determine flash protection boundaries

  • To determine incident energy

  • To determine the hazard/risk category for PPE selection


Slide6 l.jpg

Dc = [2.65 X MVAbf X t]1/2

Methods for Evaluating Arc Flash

NFPA 70E Equations and Tables

IEEE Standard 1584

Software Programs

Electrical System Analysis


Slide7 l.jpg

Limits of Approach

Exposed Energized Part

Prohibited Approach Boundary

Flash Protection Boundary

Restricted Approach Boundary

Limited Approach Boundary

Note that the outer boundary is for flash protection. All other boundaries are for shock protection.


Slide8 l.jpg

Flash Protection Zone

  • Outer zone of flash protection

  • Employees in this zone must wear flash protective equipment


Slide9 l.jpg

Limited Approach Zone

  • Only qualified people can enter this zone.

  • Must wear flash protective equipment

  • Unqualified workers prohibited


Slide10 l.jpg

Restricted Approach Zone

  • A person in this zone is in restricted space

  • Qualified people only

  • Approved written plan required

  • PPE required

  • Must keep as much of body out of restricted zone as possible

  • No body part may cross prohibited line


Slide11 l.jpg

Prohibited Approach Zone

  • Being in this zone is the same as being in contact with the live part

  • Qualified people only

  • Must have specified training

  • Approved written plan and risk hazard analysis

  • PPE for working on live parts required


Slide12 l.jpg

Using the NFPA Tables

Panelboards rated 240v and below

Task Hazard/Risk V-Rated V-Rated

Category Gloves Tools

Circuit breaker (CB) or

fused switch operation

with covers on 0 N N

Work on energized parts,

including voltage testing 1 Y Y

Remove or install circuit

breakers or fused switches 1 Y Y

When you use this table, ALL corresponding notes must be taken into consideration.


Slide13 l.jpg

Using the NFPA Tables

600v Class Motor Control Centers

Task Hazard/Risk V-Rated V-Rated

Category Gloves Tools

Work on energized parts,

including voltage testing 2* Y Y

Insertion or removal of

individual starter “buckets”

from the motor control

center 3 Y N

Application of safety

grounds, after voltage test 3 Y N

*A double-layer switching hood and hearing protection are required for this task in addition to other Category 2 requirements.

Note: When you use this table, ALL corresponding notes must be taken into consideration.


Slide14 l.jpg

Steps for Task Analysis

  • Involve everyone who will work on the job/project.

  • Identify every step that must be taken to complete the job/project.

  • For each step, identify the electrical procedures that will be performed.


Slide15 l.jpg

Steps for Task Analysis

  • Obtain or create drawings and other documents pertaining to the electrical system(s) that will be involved.

  • Identify the hazards associated with the job/project.


Slide16 l.jpg

Steps for Task Analysis

  • Agree on safety procedures that everyone will follow.

  • Determine the proper tools that need to be used for the job/project.

  • Determine the PPE that must be used for the job/project.


Slide17 l.jpg

Fall Hazards

Why is it important to consider falls when evaluating electrical safety?


Slide18 l.jpg

Case Study

  • What hazards were present in this situation?

  • What did the management and employees do wrong?

  • How could an incident like this have been prevented?