potential energy

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Transcript potential energy

Health and Safety
Electrical Safety
Chemical Safety
MSDS
Electrical Safety
Electrical Safety
• Topics to be covered:
– Basic Electrical Systems and Components
– Arc Flash
– Electrical Safety
Basic Electrical Systems Components
• Voltage:
– Voltage deals with the pressure, similar to pressure
which moves water through a garden hose. Voltage is
used to move electrons from their point of origin to
their destination; available in designation of
110,208,220-240,277,480 and higher.
• Amperage:
– Amperage deals with the flow of electricity AKA
current. Think of it as the water in the garden hose.
• Ohms:
– Ohms deals with resistance. Think of it as kinking a
garden hose.
Conduction
• Electricity is trying to move from its point of
origin to ground.
• It travels through objects which are called
conductors: Think of this as the garden hose.
• Conductors contain a high level of free
electrons.
– Examples include: silver, copper, gold, aluminum,
iron, steel, brass, bronze, mercury, and many
more.
Insulators
• An insulator has little or no free electrons.
– Examples include: glass, rubber, oil, asphalt, fiberglass,
porcelain, ceramic, quartz, plastic, air, and many
more.
• Electrical current flows at a rate of 186,000 miles
per second.
• Electrons only flow where there is conductivity…
if you interrupt the flow of electrons as they flow
from their point of origin you will become the
conductor.
Ground Fault Circuit Interrupter
• Ground fault occurs when a live circuit’s flow
is interrupted and channeled to ground.
• GFCI or Ground Fault Circuit Interrupters
prevent electrical shocks in moist
environments, such as in a restroom.
• Once the GFCI senses a leakage from the
circuit; the circuit is opened (neutralized)
protecting the system and the user.
Arc Flash
• What is arc flash?
– A release of explosive energy.
• Caused by a phase to ground .
• Or a phase to phase ground.
• How does an arc flash occur?
– Dropped tools, corrosion, dust.
– Working on live circuitry .
• Who is effected by arc flash?
– Any one who works on an electrical system.
Arc Flash
• NFPA-70E regulates the way qualified people
address live electrical circuits.
• Label and establish boundaries for potential
arc flash components.
• The best way to reduce arc flash is to deenergize circuits before beginning to work on
them.
• Lock out Tag out.
• Use PPE’s.
Electrical Safety
• Electrical shock produces two results:
– Burned internal tissues and organs.
– Over rides neural impulses which causes
involuntary muscle reactions. During electrical
shock, a victims muscles tend to clench rather
than release.
• This same shock can override the hearts natural
rhythms.
– This is the same principle used to create the taser.
Electrical Safety Cont.
• Zero Energy State
– Is a reference to reducing: Dangerous voltage,
spraying pressure, hydraulic pressure, pneumatic
pressure, suspended weight, chemical energy, or
nuclear energy.
• Always neutralize all potential energy sources
before working on an electrical circuit.
– Voltage being defined as a potential energy source
– Circuits should be open – before beginning work.
Lockout Tag Out
• A lock-out/tag-out procedure works like this: all individuals
working on a secured circuit have their own personal padlock or
combination lock which they set on the control lever of a
disconnect device prior to working on the system. Additionally,
they must fill out and sign a tag which they hang from their lock
describing the nature and duration of the work they intend to
perform on the system. If there are multiple sources of energy to
be "locked out" (multiple disconnects, both electrical and
mechanical energy sources to be secured, etc.), the worker must
use as many of his or her locks as necessary to secure power from
the system before work begins. This way, the system is
maintained in a Zero Energy State until every last lock is removed
from all the disconnect and shutoff devices, and that means every
last worker gives consent by removing their own personal locks. If
the decision is made to re-energize the system and one person's
lock(s) still remain in place after everyone present removes theirs,
the tag(s) will show who that person is and what it is they're
doing.
(http://openbookproject.net/electricCircuits/DC/DC_3.html)
Emergency Response
• What to do if someone has suffered an electrical
shock.
– Call for help, utilize co-workers, staff members, 911.
– Disconnect and isolate the source of potential energy.
– Sometimes the disconnect may not be obvious.
– Make sure you have reviewed with your staff the locations of
switch gear and power disconnects.
– If a person is froze to the circuit and you cannot
immediately find a disconnect, it is possible to use a
nonmetallic object to remove the person from the
circuit.
Emergency Response
• Assisting the victim.
– Check for breathing and pulse.
– If the victim requires CPR and you are trained in
CPR follow proper protocol.
• If the victim is conscience, have them lay on
the ground until medical professionals arrive
on site. Elevating them could trigger further
problems.
Using a Meter
• Meters have various settings.
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V with a sine wave for AC Voltage.
V with a two parallel lines for DC Voltage.
A with two parallel lines for DC Amperage.
A with a sine wave for AC Amperage.
A horseshoe representing resistance or ohms.
Generally there are three sockets.
• The black wire is always connected to the common
socket.
• The red lead can be plugged into the Volts/Resistance
socket or the Amps socket.
Using a Meter Cont.
• When measuring voltage, always test your meter
on a nearby source to verify it is working
correctly.
• When measuring resistance or continuity, always
verify the power to the circuit has been
disconnected.
• When measuring current (Amps), always use
caution as the meter becomes a part of the
closed circuit; also move the red lead from
volts/resistance to amps.
Final Word
• Electricity is a safe and useful form of energy.
• Electricity does have potential hazards.
• Hazards can be eliminated or reduced by
obtaining proper training, utilizing tools in a
safe manner, and by using proper protective
equipment.
• Only trained personnel should perform repairs
or service electrical circuits.
Links for Further Study/Reference
• http://openbookproject.net/electricCircuits/index.htm
• http://lewellyn.com/pdf/os_pdf/Arc%20Flash%20Myths%2
0and%20Misconceptions.pdf
• http://www.powersafetypro.com/images/Fast_Facts_on_A
rc_Flash_-_APS.pdf
Chemical Safety
pH Scale
• To understand chemicals we need to
understand pH.
• pH is a scale which measures the acidity and
the alkalinity of a given chemical.
• pH scale – The pH of pure water is 7; which is
neutral. The lower the number the more
acidic the chemical; the higher the number
the higher the alkalinity .
pH is measured in
increments of ten.
Example: pH of 4 is
10 times stronger
than a pH of 5. A
PH of 3 is 100
times stronger
than a pH of 5.
General Safety Rules
• Never mix two chemicals together unless the
label states to do so.
• Never mix an acid and a base (alkaline)
together.
• Keep food and cosmetics away from chemicals
– Examples include: custodial closets, custodial
carts, and so on.
• All chemicals, at all times, must be labeled.
General Safety Rules Cont.
• Lock rooms where chemicals are stored to
prevent unauthorized/untrained people from
gaining access to chemicals.
• Do not leave chemicals used in public spaces
unattended.
– Example: Squirt gun fight with the chemical
bottles.
• Every chemical used needs an MSDS.
General Safety Rules Cont.
• Have a written plan.
– What chemicals are on site (inventory)?
– Where are right to know documents kept?
– Who is responsible to facility the chemical safety
program?
– What to do in an emergency.
• Have PPE’s available and mandate employee
use.
PPE’s
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•
•
Evaluate where PPE’s are needed.
Select equipment.
Require compliant use.
Communicate to employees the necessity of
using PPE’s.
• Train employees to use PPE’s correctly.
– Explain the limitations of PPE’s.
– Explain how to maintain PPE’s.
Types of Custodial Chemicals
• Solvents:
– Break down and dissolve grease.
– Once mixed with water they have a pH of 7.5-9.0
– Example: Natural Degreaser.
• Acid Cleaners:
– Used to remove mineral deposits.
– Examples: lime, urine, rust.
– Example: Bowl Cleaner.
Types of Custodial Chemicals
• Alkaline Cleaners
– High alkaline cleaners are used to remove wax and
paint.
– Examples: Extreme, Rip Saw, Paint Thinner, Bleach
– Low alkaline cleaners are used to remove soot and
ink.
• Bacterial/Enzyme
– Eats and destroys odor producing bacteria.
– Example: Push.
Specific Training: Chemical Policy
• 88% of all loss time injuries in our industry are
caused by chemicals – loss time meaning 3 or
more days of lost time.
– 12% of injuries are caused by breathing chemicals.
– 36% of chemical injuries result in skin irritations and
burns.
– 40% of chemical injuries result in eye irritation or
burns.
– While 12% of injuries in our industry are non-chemical
related.
Specific Training: Chemical Policy
• What cleaning products have the most risk:
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Bowl cleaners.
Metal cleaners w/ perchloroethylene.
Carpet spotters w/ perchloroethylene.
General purpose cleaners w/ butoxyethanal, sodium
hydroxide & ethanolamine.
Floor stripper or baseboard stripper.
Heavy duty degreasers w/sodium hydroxide.
Graffiti remover w/ butoxyethanol.
Glass Cleaner with w/ butoxyethanol.
Disinfectant w/bleach, phenol, quats, or hydrogen
peroxide.
Responding to an Emergency
• Stay calm.
• Call for help: 911, and other staff members.
• If the victim is suffering eye irritation: Wash
contaminants out of their eye?
• If inhalation has occurred: Move victim to an
area of fresh air.
• Burns and ingestion: Follow MSDS
recommendations.
Additional Study/Reference
• http://osha.gov/OshDoc/data_General_Facts/
ppe-factsheet.pdf
• http://www.betco.com/SiteCollectionDocume
nts/Training%20Workbooks/9089192%20Basic%20Cleaning%20Workbook.pdf
• http://staff.jccc.net/pdecell/chemistry/phscale
.gif
Material Data Safety Sheets
Specific Training: MSDS
• Understanding an MSDS’s is the key to
understanding chemical safety.
• A chemical that is classified as a hazard will
have an MSDS associated with it.
– Examples include:
• Pesticides, herbicides, and other lawn chemicals.
• Pool chemicals, cleaning chemicals, feed water, and
water treatment chemicals.
• Industrial products, lubricants, fuels, paint, and varnish.
Product Name:
PPE’s:
This box shows what
protective
equipment is needed
when working with
this chemical
Product Content:
What are the chemical
compounds or ingredients
used to manufacture this
product?
Health Effects:
How could this
product affect my
health?
First Aid:
In the case of an
emergency how do
we administer aid?
Fire Fighting:
What precautions need to
be taken in the event of a
fire?
Spills:
Storage:
What needs to be
done in the case of
accidental release?
How do we store
this chemical
safely?
PPE’s:
What precautions
should I take to
protect my health
when using this
product?
Scientific Data:
Here is a listing of all the scientific data
and makeup of the chemical? What is
the PH level of this product? Is it an
acidic product, neutral product or an
alkaline product?
Stability and Reactivity:
What will the product react
with?
Toxicological
What effects does
this product have
on humans?
Ecological:
How does this
product impact
the environment?
Disposal:
How do we
properly dispose
of this product?