NFPA 70E & Trane

Jim King Trane Carolinas District Safety Leader

(What Trane does and what you may need to do)

What is NFPA 70E® ?

Electrical Safety Triangle

1 Fatality

10 Recordable Injuries

10 to 1

Safety Triangle

1 Fatality

30 Lost Time Injuries

300 Recordable Injuries

30,000 Near Misses

300,000 At-Risk-Behaviors

300 to 1

A National consensus standard and a “Standard for Electrical Safety in the Workplace”

Is part of the National Electrical Code and has been adopted by OSHA as an

enforcement standard.

NFPA 70E was originally developed at OSHA’s request in 1976 to assist OSHA in

preparing electrical safety standards.

2

Why do anything?

OSHA- Between 1973 to 1993, 78% of elec equip related injuries were caused by Arc exposure. Injuries mainly burns & blindness

3

Annually

U.S. averages 4,000 non-disabling electrical contact injuries

Annually

U.S. averages 3,600 disabling electrical contact injuries

Every day 1 person is electrocuted in the workplace

Electrocutions are 4th leading cause of traumatic occupational deaths

Each year +2,000 workers are sent to burn centers with electrical burns

Safety First

Arc Flash Characteristics

1. Electric arcs produce some of the highest temperatures

known to occur on earth – up to 35,000 degrees

Fahrenheit. This is four times the surface temperature of

the sun

2. All known materials are vaporized at this temperature.

When materials vaporize they expand in volume (Copper

– 67,000 times, Water–1670 times). The air blast can

spread molten metal to great distances with force.

3. Rapidly expanding gases, extreme pressure and sound

waves, molten metal and metal plasma.

4. “Explosion in a Box”

4

NFPA 70E - Standard for Electrical Safety

Requirements for Employee Workplaces

• First published in 1979. 2009 edition was adopted in 2008.

• 2012 edition is the current edition

• Arc flash hazard was first addressed in the 2000 edition.

• 2015 edition to be released this fall.

• NFPA 70E sets concise rules on PPE requirements and safe

distances.

• Table 130.2(C) list the approach boundaries to live (energized)

parts.

• NFPA 70E was originally developed at OSHA’s request in 1976

to assist OSHA in preparing electrical safety standards.

Safety First

Standards Interaction

OSHA 29 CFR 1910

SUBPART S

NFPA 70-E

National Electric Code

IEEE Std 1584-2002

NFPA-70

(Institute of Electrical & Electronics Engineers)

Things

What we install

People

How we behave

2012 edition was approved as an American National Standard on

August 31, 2011. Effective September 1, 2011

(Supersedes all previous editions)

6

Safety First

Evolution of Electrical Safety

From NFPA 70E Handbook, 2004 Edition, p17 (Explanatory Commentary)

“Fire, shock, and electrocution have been considered to be electrical hazards for many years. Since

the publication of NFPA 70E, 1995 edition, arc flash has been considered to be an electrical hazard.

The arc flash hazard currently is defined to consider only the thermal aspects of an arcing fault.

Other hazards include flying parts and pieces and the pressure wave that is generated in an arcing

fault. Other electrical hazards also might be associated with an arcing fault.”

Fire

Shock

Electrocution

+

Arc Flash

Brief History of Electrical Safety

"The Other Electrical Hazard: Electric Arc Blast Burns” 1980

Ralph Lee (former consultant from DuPont) - published in the IEEE

8

• 1888 “The War of Currents”

Brief History of Electrical Safety

NECA = National Electrical Contractors Association

IBEW = International Brotherhood of Electrical Workers

9

Arc Flash Causes

1. Dust and impurities

2. Corrosion

3. Condensation

4. Spark discharge – Accidental contact: dropping tools

5. Over voltage across narrow gaps

6. Failure of insulating materials

7. Improper work procedures

10

Creating an NFPA 70E® Compliant Program

• Develop Electrical Safety Program – Written electrical safety procedure

– Safe work practices

– Training requirements

– PPE requirements

• Conduct Shock and Flash Hazard Analyses on all electrical equipment to determine appropriate levels of protection

• Train and outfit all affected personnel

Where did we go from here ?

(What Trane did)

11

Start With a Hazard Risk Analysis

Hazard/Risk Analysis is a decision making process:

• Evaluate equipment and circuit information to determine the degree and

extent of hazards

• Determine “Shock Approach Boundaries”

• Determine “Flash Protection Boundary”

• Determine “Incident Energy Exposure”

• Determine appropriate Personal Protective Equipment (PPE)

Must perform Shock and Flash Hazard Analyses when working

“on or near” energized parts (within Limited Approach Boundary).

12

Shock Hazard Analysis

• Protects against Contact with energized equipment

• Use highest voltage level of exposure

• Boundary distance based solely on voltage

• Boundaries drawn from table in standard – no calcs necessary:

– Limited – a safe approach boundary. Only qualified employees and

escorted unqualified employees may cross

– Restricted – Only qualified employees may cross. When working within this boundary, must use special precautionary techniques and PPE

– Prohibited – Only qualified employees protected by insulating materials

13

Safety First

Approach Boundaries

Restricted

Approach

Boundary

Condition

Nominal System

Voltage Range,

Phase to Phase

Exposed

Movable

Conductor

Exposed Fixed

Circuit Part

Includes

Inadvertent

Movement

Adder

Prohibited

Approach

Boundary

1 0 to 50 Not Specified Not Specified Not Specified Not Specified

2 51 to 300 10 ft. 0 in. 3 ft. 6 in. Avoid Contact Avoid Contact

3 301 to 750 10 ft. 0 in. 3 ft. 6 in. 1 ft. 0 in. 0 ft. 1 in.

4 751 to 15kV 10 ft. 0 in. 5 ft. 0 in. 2 ft. 2 in. 0 ft. 7 in.

5 15.1kV to 36kV 10 ft. 0 in. 6 ft. 0 in. 2 ft. 7 in. 0 ft. 10 in.

Limited Approach Boundary

1. “Limited” Boundary - Must be Qualified Person

2. “Restricted” Boundary - Must wear Electrical PPE

3. “Prohibited” Boundary - Must wear PPE as if direct contact is being made.

Working with Control Panel door open – in Restricted Approach Boundary

Table 130.4(C)(a)

NFPA 70E® 2012

Page 24

Flash Hazard Analysis

• Designed to prevent injury from the heat generated in an arc event – not contact (Shock)

• A Flash Hazard Analysis Shall Determine:

– Flash Boundary

Approach boundary from exposed energized parts within which a person without proper PPE could receive beyond a 2nd degree burn.

– Incident heat energy of possible arc flash based on:

Available fault current

Fault clearing time

Distance from exposed equipment

Directional dissipation of energy (arc-in-the-box scenarios)

• PPE Requirements within the Flash Boundary

15

Arc Flash Boundaries (NOT S-H-O-C-K)

• To protect from thermal burn due to arc flash

• Electrical systems 600V or less:

– 4 feet, or the calculated distance based on established

algorithms

• Electrical systems over 600V:

– Boundary based on incident energy as calculated or as given

in default tables in Standard

Work within the Flash Boundary will require AR Clothing &

electrical PPE to protect the employee from arc flash injury

(Good rule of thumb is 10 feet)

(Think of others without AR & PPE)

Office workers Customers Plumbers

Teachers Visitors Students

2012: The default 4′ arc flash protection boundary of earlier 70E editions has been removed from 70E 2012. This

boundary is now specified in inches for each unique situation and comes from one of two task tables: Table

130.7(C)(15)(a) for AC and Table 130.7(C)(15)(b) for DC. These tables also list the fault current, clearing time, and working

distance of protective devices in the heading of each table section.

16

FLASH BOUNDARIES

Restricted Shock Boundary: Qualified Persons Only

Flash Protection Boundary (FPB)

Must wear appropriate clothing & PPE

FPB dependent on fault level and time duration.

Prohibited Shock Boundary: Qualified Persons Only. PPE as

if direct contact with live part

Eq

uip

me

nt

Limited Shock Boundary: Qualified or Unqualified Persons*

* Only if accompanied by Qualified Person

Limited Restricted Prohibited

“Sparky”

17

Flash Hazard Analysis

• Determines the Flash Protection Boundary

• Determines the required PPE

• 2 Methods available:

1. Can use Default Tables in the NFPA 70E Standard – Classifies work tasks in a specific Hazard Risk Category (HRC)

– Specifies required PPE as a function of HRC

2. Can calculate the incident energy to employees if a fault occurred; Can then specify the required PPE based on predicted hazard level.

We compared default tables to calculated values:

• Used conservative, but reasonably expected input parameters

• Used 2 different calculation models (took highest values)

• Found calculated values to be less than default tables

18

Flash Hazard Analysis Method # 1 Default Tables

Tasks Performed on Energized Equipment

Panel boards or other equipment rated > 240 V and up to 600 V

Hazard/Risk

Category

Rubber

Insulating

Gloves

Insulated and

Insulating Hand

Tools

Parameters:

Maximum of 25 kA short circuit current available; maximum of 0.03 sec (2 cycle) fault clearing

time; minimum 18 in. working distance

Potential arc flash boundary with exposed energized conductors or circuit parts using above

parameters: 30 in.

Perform infrared thermography and other non-contact inspections outside the restricted

approach boundary

1 N N

Circuit breaker (CB) or fused switch operation with covers on 0 N N

CB or fused switch operation with covers off 1 Y N

Work on energized electrical conductors and circuit parts, including voltage testing 2 Y Y

Remove/install CBs or fused switches 2 Y Y

Removal of bolted covers (to expose bare, energized electrical conductors and circuit parts) 1 N N

Opening hinged covers (to expose bare, energized electrical conductors and circuit parts) 0 N N

Work on energized electrical conductors and circuit parts of utilization equipment fed directly by

a branch circuit of the panelboard

2 Y Y

NFPA 70E® 2012 Edition (Page 33-38)

Table 130.7(C)(15)(a) Hazard/Risk Category Classifications and Use of Rubber Insulating Gloves and

Insulated and Insulating Hand Tools-Alternating Current Equipment (Formerly Table 130.7(C)(9)

19

Flash Hazard Analysis Method # 2 Calculation Method

Formula: EMB = 1038.7 DB

-1.4738 tA[0.0093F2-0.3453F+5.9675] cal/cm2

EMB = Incident Energy (cal/cm2)

DB = Distance, (in.) [for Distances > 18 inches]

tA = Arc Duration, (sec.)

F = Bolted-Fault Short Circuit Current [16KA to 50kA]

Incident Energy Calculation (Arc in a 20 in. cubic box, open on 1 side)

Ref: “Predicting Incident Energy to Better Manage the Electric Arc Hazard on 600 V Power

Distribution Systems”, Dougherty, RL; Neal, TE; Floyd II, HL. IEEE Paper, 1998.

From IEEE 1584 – Guide to Performing Arc Flash Hazard Calculations

20

Flash Hazard Analysis Calculation Method

Can also use computer models such as:

Duke Power Arc Calculator, and several

other commercially-available products

We used both the IEEE method and the Duke Power

Calculator – Followed the IEEE Method.

IEEE Method gave the most conservative results.

21

Safety First

Confused yet?

i cdnuolt blveiee taht I cluod aulaclty uesdnatnrd waht I

was rdanieg. The phaonmneal pweor of the hmuan mnid,

aoccdrnig to a rscheearch at Cmabrigde Uinervtisy,

it dseno't mtaetr in waht oerdr the ltteres in a wrod are, the

olny iproamtnt tihng is taht the frsit and lsat ltteer be in the

rghit pclae. The rset can be a taotl mses and you can still

raed it whotuit a pboerlm. Tihs is bcuseae the huamn mnid

deos not raed ervey lteter by istlef, but the wrod as a wlohe.

Azanmig huh?

22

Safety First

Focus On Engineering and Admin Controls

CSO S&H -42, Trane’s Electrical Procedure, Section 5.1.6 (p-6)

23

OSHA 1910. 335 “Safeguards for personnel protection”

(a) (2) (ii)

“Protective shields, protective barriers, or insulating materials shall be used to protect each employee from shock, burns, or electrically related injuries while that employee is working near exposed energized parts which might be accidentally contacted or where dangerous electric heating or arcing might occur. When normally enclosed live parts are exposed for maintenance or repair, they shall be guarded to protect unqualified persons from contact with the live part.”

Safety First

1. Affects mostly equipment owners, but may affect service organizations if they have all necessary info to determine hazard class.

2. Mechanical systems OEMs only supply internal circuit protection. Customer determines equipment disconnecting means and has a unique electrical infrastructure.

3. Old Requirement – Label required if work is expected to be done in an energized state, or when verifying power off. A generic label stating an Arc Flash Hazard Analysis is required – meaning “Follow the Table Method”.

4. New Requirement – Each piece of equipment must have a label with the incident energy or required PPE ensemble required to do work. No more generic labels

5. Arc Flash Hazard Analysis must be reviewed every 5 yrs, or whenever a major modification occurs (no definition of major modification in Standard). Therefore, the Label Must Be Dated.

Labeling Equipment

(C) Equipment Labeling. Electrical equipment such as switchboards, panel boards, industrial control panels,

meter socket enclosures, and motor control centers that are in other than dwelling units, and are likely to

require examination, adjustment, servicing, or maintenance while energized, shall be field marked with a label

containing all the following information: Changed From 2009

•130.5(C): Revised to identify types of electrical equipment required to be labeled, and expanded and clarified

the information required to be included on the label. Added requirement to document the method used to

determine information on label. Exception added to cover existing equipment labels.

(1) At least one of the following:

a. Available incident energy and the corresponding working distance

b. Minimum arc rating of clothing

c. Required level of PPE

d. Highest Hazard/Risk Category (HRC) for the equipment

(2) Nominal system voltage

(3) Arc flash boundary

Exception: Labels applied prior to September 30, 2011, are acceptable if they contain the available

incident energy or required level of PPE.

The method of calculating and data to support the information for the label shall be documented.

2012 NFPA 70E® Labels

25

Safety First

LABELING REQUIREMENTS

1. Trained and/or retrained every 3 years (NFPA 70E section 110.2 (D)(3))

2. 105.3: Revised 110.3 to clarify that employees are to be trained prior to

implementing safety related work practices.

3. 110.1 (C): Specifies that training on the release of victims from exposed

energized equipment is required for employees who are exposed to shock

hazards and those who are responsible for taking action in case of such

emergencies, as well as an added provision for certifying employees on using an

automated external defibrillator.

4. 110.2(D)(1)(c): Clarifies that on-the-job training associated with this requirement

is necessary for the employee to be considered a qualified person and to provide

clarity on the duties being performed.

5. 110.2(D)(2): Clarifies the necessary level of training for unqualified people on

electrical safety-related work practices.

6. 110.2(E): Requires that the “content of training” be included in the training

documentation. Maintained for duration of employment

27

2012 NFPA 70E® Changes for Training

Engineering and Admin Controls

1. Reduce Fault Current and Duration of Arc Flash

– Change type of fusing, where appropriate

Faster clearing times

Current-limiting fusing

– Manufacture equipment with IP20 (Touch-Safe) components in control panels

– Replace breakers with faster operating devices such as fuses

2. Reduce Exposure – Add barriers (installed or portable) eg 1kV plastic rolls

– Add distance with different tools; extended probes; etc..

– Install external measurement points

Use of PPE to Control the Hazard is the Last Resort

Trane and other OEMs

starting to do this

28

Current-Limiting Fuses

“(4) For equipment protected by upstream current limiting

fuses with arcing fault current in their current limiting

range (½ cycle fault clearing time or less), the hazard/risk

category required may be reduced by one number.”

[note (4) above taken from NFPA 70E 2012 page 37]

Fuses with a rejection feature to prohibit the

installation of non-current-limiting fuses

29

Safety First

Should we spend all this money on PPE?

30

Safety First

Electrical PPE Requirements

Electrical PPE (rubber gloves, hard hat / arc face shield, AR clothing) is required for troubleshooting, applying LOTO and testing dead. After that,

1. The line side terminal of the disconnecting device may still be energized.

2. According to this standard, if you are “exposed” to energized parts, electrical PPE is still required.

“Exposed” means being within the Limited Approach Boundary, which is 1 ft, for circuits 120 – 480 V.

3. You can eliminate “exposure” and remove the PPE if you can “Insulate” or “Isolate” yourself from the energized parts.

4. Insulate by placing an insulating material over the part.

5. Isolate by placing a rigid barrier over the part to prevent contact, or ensure your body and all conductive tools remain > 1 ft. away.

PPE requirements based on your distance from “Exposed

Energized Parts”, not the equipment you’re working on

Safety First

Hazard Risk Category 1 • Jeans no longer allowed

• 2004 Ed. Allowed12 oz denim instead of FR pants

• FR pants are now required

Hazard Risk category 2* • Face Shield with FR balaclava, or arc flash hood

• 2004 Ed. did not require the balaclava

All Hazard Risk Categories • Hearing protection required – ear canal inserts only

• When layering over non-FR natural fibers (eg, cotton), the outer layer by itself must meet the required level of protection

• Cannot use cotton as part of the ATPV or EBT calculations

PPE Requirements

PPE Selection From Calculations

For Most Testing and Troubleshooting Work

Synthetic fibers, such as polyester, nylon, acetate, rayon, either alone

or in blends are not permitted – they melt at low temperatures,

adhere to the skin and increase the extent of injury.

Outer layer must AR

Voltage Clothing Gloves Other PPE

Safety Glasses

Class E Hard Hat

Safety Glasses

Class E Hard Hat with 8 Cal.

ATPV Face Shield

Balaclava HRC 2

Ear Canal Inserts

> 600 volts STOP! You must receive specific training, be qualified, and equiped for > 600 volts.

50 - 120 Volts

FR long-sleeve shirt, FR

T-Shirt and FR pants or

HRC 2 Coveralls

Leather Gloves (Class 00 if

possiblility of contact)

121 - 600 Volts

FR long-sleeve shirt, FR

T-Shirt and FR pants or

HRC 2 Coveralls

Class 0 (rated to 1kV)

Insulated Rubber Gloves w/

Leather Protectors

33

About Insulated Tools (Screwdrivers)

Working it hot (Maintenance & Repair) Trane doesn’t perform “Hot Work”

34

-not required because we don’t perform “hot work”

(i.e. screw driver tip on an energized wire or terminal).

But as a precaution, anytime a live panel door is open...

-potential of dropping or slipping with an un-insulated tool...

therefore using insulated tools are an added precaution.

Good idea, but not required

Insulated screw drivers?

Safety First

Hazard Risk

Category 0 Hazard Risk

Category 1

Hazard Risk

Category 2

Hazard Risk

Category 3

Hazard Risk

Category 4

TRANE

HRC PPE

35

Voltage Testing

“When using the voltage meter to test voltage after de-energizing a circuit, the

employee will:

1. Test the meter on a known, live source

2. Test the conductor or circuit part for the presence of voltage

3. Test the meter again on the known, live source before beginning work on the conductor or

circuit part.”

36

Safety First

Multimeters

Today’s electrical measurement equipment is designed to meet the IEC (International Electrotechnical Commission) standards for transient overvoltages. The IEC standard specifies categories of overvoltage based on the distance from the power source and natural damping of transient energy that occurs in electric distribution systems. IEC overvoltage installation categories are defined by the location of the equipment to be tested. They are: Category I is the signal level for telecommunications and electronic equipment. Category II is the local level for fixed or non-fixed powered devices (i.e. lighting, appliances, portable equipment, etc.) Category III is the distribution level – fixed primary feeders or branch circuits. These circuits are usually separated from utility service by a minimum of one level of transformer isolation. Category IV is the primary supply level. This refers to overhead or underground utility service to an installation. Within each installation category there are voltage classifications which determine the maximum transient withstand capability of the instrument.

Installation Category Voltage Classification Maximum Transient Capability

CAT II 600 V 4000 V peak impulse transient

CAT II 1000 V 6000 V peak impulse transient

CAT III 600 V 6000 V peak impulse transient

CAT III 1000 V 8000 V peak impulse transient

CAT IV 600 V 8000 V peak impulse transient

CAT IV 1000 V 12000 V peak impulse transient

Installation Category Locations

To ensure the right protection is provided for the job, it is recommended that Category IV multimeters be used; however, the minimum acceptable multimeter rating is Category III. When purchasing Category III or Category IV multimeters; make sure that the test leads supplied by the manufacturer are also rated as Category III or Category IV. When making up your own test leads, make sure all the components, connectors, wire, and test probes are rated Category III or Category IV. Note: Pomona and Belden are just a couple of manufactures that provide Category III and IV test leads and/or test lead components. Manufacturers’ specification and rating sheets can be readily obtained from the internet. As a standard practice, all test leads should undergo a visual inspection prior to use.

MINIMUM METER REQUIREMENTS

Last known earthly

residence of automotive fuse used to

replace original fuse

Test leads survived intact

Handheld test tool safety

Misusing measurement tools

Common errors

• Connecting a meter to a voltage source with the

meter set up in inline amps

– Amps mode on meter is almost a short circuit

• Trying to measure ohms or continuity

on a live circuit

– Some older meters cannot handle

the full voltage on the ohms function

Probe tips burned off

250 V fuse

didn’t open in

time

Poor quality leads and probes led to

injury.

Handheld test tool safety

Three common errors that are avoidable

Common DMM safety hazards

• Measuring voltage while test

leads are in the current jacks =

short-circuit!

Protection: Fluke meters use

high energy fuses.

• Contact with ac or dc power

source while in ohms mode.

Protection:Use a meter with “Overload Protection.”

Functions are self-protected to the meter’s

rated voltage.

• Using meter above its rated voltage, i.e., on medium

voltage circuits.

Protection: Good karma

Technician Clothing Before NFPA 70E®

- Just Kidding….

42

Technician Clothing Before NFPA 70E®

Synthetic fibers, such as polyester, nylon, acetate, rayon, either alone or in blends are not permitted – they melt at low

temperatures, adhere to the skin and increase the extent of injury.

43

Relationship with Contractors

“When contractors are hired to help perform work on customer equipment, the following

responsibilities and actions are required on behalf of Trane and the Contractors:

Host Employer Responsibilities

• Notify Contractor of electrical hazards associated with the work that might not be

recognized by the Contractor.

• Notify Contractor of information needed by the Contractor to properly assess the extent of

hazards.

Contractor Responsibilities

• Employees will be made aware of site-specific hazards communicated from host

employer.

• Employees will follow NFPA 70E rules and safety-related work rules required by the host

employer.

• Advise the host employer of unique or unanticipated hazards found.

• Advise host employer of corrections to rule violations”

• Document meeting

44

Safety First

High Voltage is a Bear!

(Discovered by a Sprint Technician)

Real

Life

Demonstration

45

Safety First

Comments or Questions?