Dangers of electricity

version 2.10.25
octobre 2022

Catherine Bittes-Hernarestien

Patrick Jacob

Introduction

Awareness of electrical hazards consists of:

  • make the public concerned aware of the dangers of electric current.

  • provide the basics in terms of electrical safety in order to perform electrical tasks safely; whether in the professional or domestic field,

  • pass the theoretical validation validation test

Generally, people who have not received safety training do not behave in a way that ensures their safety, one of the causes being the invisibility of electrical current. It is necessary to help them:

  • avoid hurting yourself or others

  • understand what it means to work safely

  • become aware of the cost of "non-security"

Définition

Definitiona hazard = a danger

Electrical Hazard

An Electrical Hazard can expose workers

What an electrical hazard can expose workers to.

Clic on the picture to see what an electrical hazard can expose workers to.

Consequences of an electric shock

What are the possible consequences of an electric shock on the body ?

Fill the gaps

A shock can cause muscle spasms,

A shock can cause cardiac arrest,

A shock can cause burns to tissues and organs ,

A shock can affect the nervous system.

What are the possible consequences of an electric shock on the body ?

Fill the gaps

A shock can cause muscle spasms,

A shock can cause cardiac arrest,

A shock can cause burns to tissues and organs ,

A shock can affect the nervous system.

Quiz:General effects of electric current

The general effects of electric current differ for man, woman and child.

For the same amount of current, women generally have worse symptoms then men.

What is the effect for each current value ?

Electric current (contact for 1s)

Effect

Below 1 mA

1 mA

5 mA

6-25 mA (women)

9 to 30 mA (men)

50 to 150 mA

1 to 4.3 A

10 A

Electric current (contact for 1s)

Effect

Below 1 mA

Not perceptible

1 mA

Threshold of feeling,

5 mA

Slight shock. Not painful.

6-25 mA (women)

Loss of muscle control

9 to 30 mA (men)

Freezing current, "can't let go". The person may be thrown away from the power source.

50 to 150 mA

Extreme pain. Respiratory arrest. Muscles reactions. Possible Death.

1 to 4.3 A

Fibrillation of the heart. Muscular contraction and nerve damage occur. Likely death.

10 A

Cardiac arrest, severe burns. Death is probable

Quiz:Vocabulary - part 1

Fill in the list of new vocabulary words on your sheet of paper

To injure / an injury

Live parts / live

A fault / faulty

Ignition

Safety procedures

A risk assessment

To weld / welding

Suitable / unsuitable

A surrounding area

An extention lead

To avoid

RCD (residual current device)

A medical treatment

To wire / to be rewired

To maim

To repair / a repair

Plugs/sockets

To take for granted

To injure / an injury

Etre blessé / une blessure

Live parts / live

Partie sous tension

A fault / faulty

Défaillant

Ignition

Allumage

Safety procedures

Les procédures de sécurité

A risk assessment

Une évaluation des risques

To weld / welding

Souder / soudure

Suitable / unsuitable

Convient / ne convient pas

A surrounding area

Une zone environnante

An extention lead

Une rallonge

To avoid

To avoid

RCD (residual current device)

DDR (disjoncteur différentiel)

A medical treatment

Un traitement médical

To wire / to be rewired

Câbler / être cablé

To maim

Mutiler

To repair / a repair

Réparer / une réparation

Plugs/sockets

Une prise mâle / femelle

To take for granted

Considérer comme acquis

Basic notions

Introduction

Safety training should cover:

  • knowledge of rules and procedures,

  • the use of tools and protections,

  • motivation to do the job the right way.

In the next step, you will have to answer a few questions on basic notions of electrical protection

Basics of Contact with Electricity

It is the level of voltage  the body is exposed to and the resistance to flow of electrical current offered by the body that determines the impact of exposure to electricity. The following factors determine the severity of the effect electric shock has on your body:

Fill the gaps with the flollowing words :

  • flows

  • resistance

  • voltage

  • path

  • The level of voltage

  • The amount of body resistance you have to the current flow

  • The path the current takes through your body

  • The length of time the current flows through your body

How Electric Current affects the Body

Electric Current affects the body when it flows through. The basic unit of current is the amp. This is the current which flows through a resistance of 1 ohm (Ω) when a voltage of 1 volt is applied across it. However, currents as low as thousandths of amps (milliamps) can have an adverse effect on the body.

The table  below gives an illustration of the types of effects various levels of currents can have on the body.

Accepted as maximum harmless current Temporary respiratory paralysis, possibility of death. Beginning of muscular contraction ("Can't let go" current.) Ventricular fibrillation, fatal if continued. Respiratory function continues. You are starting to feel something
0,5mA
5mA
10mA
30 à 75mA
1A et plus

Personal Protective Equipment (PPE)

Personal Protective Equipment (PPE) means any device or appliance designed to be worn or held by an individual for protection against one or more health and safety hazards.

Tapis isolants Gants isolants
Electrical insulating gloves
Low voltage detectors
Insulating mats
Helmet with integrated face shield
Insulating boots class

The first step to do

If a worker has come into contact with electricity the worker may not be able to remove themselves from the electrical source.

The human body is a good conductor of electricity.

If you touch a person while they are in contact with the electrical source, the electricity will flow through your body causing electrical shock.

What is the first step to do in this case ?

attempt to of the electricity. the source turn off Firstly

Basics of Contact with Electricity

  • The level of voltage

  • The amount of body resistance you have to the current flow

  • The path the current takes through your body

  • The length of time the current flows through your body

How Electric Current affects the Body

0,5mA
You are starting to feel something
5mA
Accepted as maximum harmless current
10mA
Beginning of muscular contraction ("Can't let go" current.)
30 à 75mA
Ventricular fibrillation, fatal if continued. Respiratory function continues.
1A et plus
Temporary respiratory paralysis, possibility of death.

Personal Protective Equipment (PPE)

Personal Protective Equipment (PPE) means any device or appliance designed to be worn or held by an individual for protection against one or more health and safety hazards.

Electrical insulating gloves
Gants isolants
Low voltage detectors
Insulating mats
Tapis isolants
Helmet with integrated face shield
Insulating boots class

The first step to do

Firstly attempt to turn off the source of the electricity.

Quiz:Vocabulary - part 2

Fill in the list of new vocabulary words on your sheet of paper

A residual current device

An earth leakage trip device

To be fitted

To be damaged

To be labelled

To overload

A socket

To be unplugged

To be discharged

A lockout / tagout

A residual current device

Un dispositif à courant résiduel

An earth leakage trip device

Un déclencheur différentiel

To be fitted

À installer

To be damaged

Être endommagé

To be labelled

Installer une pancarte

To overload

Surcharger

A socket

Une prise

To be unplugged

Être débranché

To be discharged

Être déchargé

A lockout / tagout

Un cadenassage / étiquetage

Be prepared to work safely

Electrical Hazards

Watch the video carefully below

To see the subtitles, clic on the gear wheel on the rigth and choose English

Be prepared to work safety

Are you prepared ?

Introduction

You have carefully watched the video "Be prepared to work safely".

You will be able to answer the following series of quizzes

Operate electric equipment correctly

If you do not operate electric equipment correctly, what can be the consequences :

  • for people :

  • for equipment :

Complete the sentences :

Contact with live parts will result in electric shocks and burns

Ignition can be provoked by a faulty equipment and cause fire or explosion.

Every company should have safety procedures that need to be respected.

Before every job it's essential to : assess potential risks check if equipment is suitable/ safe to use and not faulty / damaged

Wet conditions

How can risks be reduced in wet conditions ? Give examples.

You can use :

Damaged equipment

Fill the gap

In wet conditions, any damaged equipment can become dead.

Devices

Give a example of devices that can be easily damaged :

Devices

Give another example of devices that can be easily damaged :

Damaged equipment

What can develop a damaged equipment ?

A damaged equipment can develop an electrical fault when you're working in a confined space.

Sockets

Can you overload sockets ?

Sockets can be overload  No

Complete the sentence :

The safest way is to unplugged electrical equipment before use it and make sure it is fully discharged

Operate electric equipment correctly

Contact with live parts will result in electric shocks and burns

Ignition can be provoked by a faulty equipment and cause fire or explosion.

Every company should have safety procedures that need to be respected.

Before every job it's essential to : assess potential risks check if equipment is suitable/ safe to use and not faulty / damaged

Wet conditions

How can risks be reduced in wet conditions ? Give examples.

You can use :

air equipment

Damaged equipment

In wet conditions, any damaged equipment can become dead.

Devices

Give a example of devices that can be easily damaged :

Extension leads

Devices

Give another example of devices that can be easily damaged :

Extension leads

Damaged equipment

A damaged equipment can develop an electrical fault when you're working in a confined space.

Sockets

Sockets can be overload  No

The safest way is to unplugged electrical equipment before use it and make sure it is fully discharged

Conclusion

Conclusion à faire

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