MODULE 4

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MODULE 4
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Excavation(Trenching Shoring)
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Excavation Trenching Shoring

• Excavating is one of the most hazardous forms of
  construction activity due to the possibility of
  cave-ins.
• Excavating emergencies are more likely to result
  in a serious injury or fatality than any other
  construction accident.
• Trench accidents result in approximately 100
  fatalities per year.

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Excavation Trenching Shoring

• By Law all underground hazards shall be
  identified before work begins.
• Utilize ONE CALL 811

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Excavation Trenching Shoring
APWA Color Codes

• Proposed Excavation
• Temporary Survey
• Electrical
• Gas
• Communications
• Potable Water
• Irrigation
• Sewer

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Excavation Trenching Shoring

• Site workers are those employees working on a
  site or location that has an excavation
  project.
• Excavation Workers are those employees working on
  the excavation project
• Site workers are not authorized to work on the
  excavation project.

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Excavation Trenching Shoring

• A competent person is defined as one who is
  capable of identifying existing and predictable
  hazards in the surroundings, or working
  conditions which are unsanitary, hazardous, or
  dangerous to employees and who has the authority
  to take prompt corrective measures to eliminate
  them

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Excavation Trenching Shoring

• Inspections
• Inspections must be performed by the competent
  person
• Prior to start of work
• As needed throughout shift
• Daily
• After rainstorms
• Other hazard changes
• Exposure reasonably expected

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Excavation Trenching Shoring

• Work Practices
• Methods to prevent cave-ins
• Shielding and shoring
• Relies on mechanical structures
• Sloping and benching
• Based on soil type

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Excavation Trenching Shoring

• Work Practices
• Good work practices shall include proper training
  of all employees on dangers associated with
  trenching and shoring.
• No employee shall be allowed on or around an
  excavation without proper personal protective
  equipment including atmospheric monitoring
  devices.

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Excavation Trenching Shoring

• No employee shall be allowed on or around an
  excavation that does not have a protective system
  in place, if necessary.
• Atmospheric testing shall be done before entering
  the trench. Additional monitoring shall be done
  as per company requirements.
• Means of exit must be within 25 feet of lateral
  travel if greater than four feet in depth.

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Excavation Trenching Shoring

• Employees shall not work in excavations where
  there is an accumulation of water unless
  precautions have been taken to protect employees.
• Precautions should include but are not limited
  to
• Special support or shield systems
• Water removal or control
• Safety harness with lifeline

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Excavation Trenching Shoring

• Hazards
• Oxygen deficient atmospheres.
• Loose rocks or soil.
• Overhead loads being carried/lifted by digging
  equipment.

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Excavation Trenching Shoring

• Personal Protective Equipment (PPE)
• Respirators employees must be fit tested and
  have proper training before use.
• Hazardous Atmospheres
• lt19.5 or gt23.5 Oxygen (MN 5207.300)
• Combustible gas gt10 LEL (LFL)
• Concentrations of toxic materials gt TLV
  established by ACGIH

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Excavation Trenching Shoring

• Some trenches qualify as a confined space.
  Therefore compliance with the Confined Space
  regulations would be required.
• Atmospheric testing shall be done
• Before employees enter the area
• Periodically to ensure the atmosphere is still
  safe
• Periodic testing shall increase if you are
  operating equipment in the trench.

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Excavation Trenching Shoring

• Emergency Non-Entry Rescue
• In the event of an emergency situation requiring
  rescue, personnel SHALL NOT attempt to enter an
  unprotected trench to perform rescue.
• Call emergency services in your area.
• Rescue services that can be performed safely from
  outside the excavation, such as hoisting a
  harnessed victim, shall be undertaken.

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Excavation Trenching Shoring

• Other rescue equipment shall include
• Breathing equipment
• Basket stretcher
• Attendees

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Hydrogen SulfideH2S
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Hydrogen Sulfide

• Hydrogen Sulfide (H2S) gas is deadly in
  relatively low concentrations.
• H2S gas is created by the decomposition of animal
  or vegetable matter.
• H2S gas may be found in oil and gas wells,
  storage tanks, sewers, mines, gas plants and
  refineries.
• What you dont know can hurt you!

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Hydrogen Sulfide

• Hydrogen Sulfide (H2S) gas is referred to by many
  names
• Rotten egg gas
• Stink gas
• Sour gas
• Sulfureted Hydrogen gas
• Sewer gas
• Devils breath

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Hydrogen Sulfide

• Greatest danger is inhalation
• SPECIFIC TRAINING IS REQUIRED
• Use of respirator
• Signs posted
• Areas monitored

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Hydrogen Sulfide

• (H2S) Properties and Characteristics
• Toxic
• Colorless
• Offensive odor
• Soluble
• Corrosive
• Heavier than air
• Flammable
• Produces toxic bi-products

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Hydrogen Sulfide

• Possible Symptoms of H2S Exposure

• Eye irritation
• Fatigue
• Throat irritation
• Skin irritation
• Headache
• Nausea

• Dizziness
• Loss of consciousness
• Vomiting
• Irrational behavior
• Coughing
• Excitement

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Hydrogen Sulfide

• Toxicity Levels
• 20 ppm Permissible Exposure Limit (PEL)
• 10 ppm Action Level
• 100 ppm Immediately Dangerous to Life and
  Health (IDLH)
• 1000 ppm Dead Right There (DRT)

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Hydrogen Sulfide

• If the event of an H2S alert and the monitor
  alarm sounds, employees are to evacuate quickly
  moving up wind or cross wind, to high ground.
• Check the wind sock or guy wire flags to
  determine wind direction.

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Fire Safety Emergency Evacuation
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Fire Safety Prevention and Protection

• Actions to be taken
• Prevent or reduce likelihood of a fire
• Alert the presence of a fire
• Enable survival
• Reduce damage
• Know the level of training of each employee
• Respond only to the level of training

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Fire Safety Prevention and Protection

• Three Elements of a Fire
• Air
• Fuel
• Heat
• All three elements are needed to begin the
  chemical chain reaction that is Fire.
• When one leg of the fire triangle is removed
  combustion stops.

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Fire Safety Prevention and Protection

• Class A Fires
• Class B Fires
• Class C Fires
• Class D Fires
• Class K Fires

D
K
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Fire Safety Prevention and Protection

• Remember the PASS System
• Pull
• Aim
• Squeeze
• Sweep

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Fire Safety Prevention and Protection

• Pull the Pin
• This will allow you to discharge the
  extinguisher.
• Aim
• Aim at the base of the fire instead of the
  flames.

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Fire Safety Prevention and Protection

• Squeeze the Handle
• This will release the pressurized extinguishing
  agent.
• Sweep
• Sweep from side to side until the fire is out.

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Fire Safety Prevention and Protection

• HOT WORK
• Examples
• Welding
• Flame Cutting
• Grinding Using a torch
• Obtain Hot Work permit prior to performing any
  Hot Work activity

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Fire Safety Prevention and Protection

• FIRE WATCH
• Duties
• Have appropriate fire extinguisher readily
  available
• Ensure conditions of permit are enforced
• Remain at hot work area for at least 30 minutes
  after completion of the hot work
• Prior to beginning work, discuss the Emergency
  Action Plan.

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Emergency Evacuation

• The immediate and rapid movement of people away
  from the threat and immediate danger.
• Emergency evacuation should be planned prior to
  any type of emergency that could exist in your
  field of operation.

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Emergency Evacuation

• All employees shall be trained and familiar with
  the emergency evacuation program.
• The program shall be displayed in an accessible
  area for all employees.
• Keep all exits clear of obstructions.
• Know your assembly point in the event of an
  evacuation.
• Be familiar with the company notification
  protocol.

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Electrical Safety
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Electrical Safety

• Electricity is a silent and invisible force that
  can kill without warning if ignored treat with
  respect and caution.
• Electricity takes multiple paths, flowing through
  the path of least resistance.
• The body can act as an excellent conductor since
  it is made up of water, chemicals and minerals.
• The body can bridge the gap between two voltage
  levels resulting in an electric shock.

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Electrical Safety

• Electrical Hazards
• Sparks from static or equipment
• Fires
• Explosions
• Faults in lines or equipment
• Fires
• Explosions
• Shocks

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Electrical Safety

• Causes of Electrical Hazards
• Hazardous conditions
• Wet surrounding
• Outdoor Activities
• Cramped spaces
• Explosive atmospheres
• Arcing
• Equipment wear and tear

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Electrical Safety

• Safe Work Practices
• Lockout/Tagout
• Proper Authorization
• Electrical protective equipment
• Keeping a safe distance from energized circuits
• Equipment Inspection
• Using proper tools (GFCI, Insulated tools)

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Electrical Safety

• Working Near Exposed Parts
• Energized Equipment anything connected or
  contacted to an electrical source. Has the power
  on!
• De-Energized Equipment being free from any
  electrical connection to a source. Has the power
  disconnected from the source!
• Example lockout/tagout

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Electrical Safety

• De-Energized Parts
• Treat any conductors and parts of electric
  equipment as energized that have been
  de-energized.
• Lockout/Tagout should always be used.

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Electrical Safety

• Energized Parts
• Only qualified employees
• May work on or with exposed energized lines or
  parts of equipment.
• May work in areas containing unguarded,
  un-insulated energized lines.

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Electrical Safety

• Overhead Line Safety
• Dont operate equipment around overhead power
  lines unless you are authorized to do so.
• If an object must be moved in the area of
  overhead power lines, appoint a competent worker
  as a spotter.
• Never touch an overhead line.
• Never assume lines are dead.

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Electrical Safety

• When a machine is in contact with overhead lines,
  DO NOT allow anyone to come near or touch the
  machine.
• Never touch a person who is in contact with a
  live power line.
• If you are in a vehicle that is in contact with
  an overhead power line, DO NOT LEAVE THE VEHICLE
  and do not touch any metal parts within the
  vehicle.
• Avoid storing materials under or near overhead
  power lines.

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Electrical Safety

• Portable equipment is not part of a fixed
  installation but when used is connected to a
  fixed installation by means of a flexible cable,
  plug and socket.
• Never raise or lower by cord
• Ensure there are grounding prongs
• No exposed or repaired wiring
• Approved portable electrical equipment
• Use a portable GFCI

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Electrical Safety

• Inspection
• Portable Electrical Equipment
• Ensure ground connection on plug ends
• Ground prong is not removed
• Inspect prior to use
• Avoid long extension cords
• Use approved couplers
• Replace damaged extension cords

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Electrical Safety

• Inspection
• Ground Fault Circuit Interrupters
• Best protection from electrical injury
• Interrupts circuit
• Protects people, not equipment
• Test periodically
• Installed between extension cord and load

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Electrical Safety

• Inspection
• Welding cable
• Inspect prior to use
• No splices within 10 feet of holder
• Repair or replaced if damaged
• Connect appropriately
• Never wrap around body part

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Electrical Safety

• Avoiding the hazards
• Never use broken or faulty equipment
• Electrical PPE
• Must be inspected
• Includes
• Gloves - Covers
• Matting - Line hoses
• Blankets - Sleeves

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Electrical Safety

• During well servicing operations, grounding is to
  be provided between the rig and wellhead with a
  grounding cable securely connected in the
  casing.
• Derrick personnel must vacate the derrick during
  thunderstorms and all workers are to move away
  from the derrick.

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Lockout/Tagout
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Lockout / Tagout

• Lockout is the process of blocking the flow of
  energy (electrical, fluid, air etc.) from a power
  source with a blocking device to eliminate the
  power to disable the equipment.
• A lockout device may be a lock, chain, block or
  special locking device that keeps the power in
  an off position.

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Lockout / Tagout

• This program does not apply to handheld power
  tools or stationary equipment whose electrical
  power may be controlled by the unplugging of
  equipment from the energy source.

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Lockout / Tagout

• Types of Energy Sources
• Kinetic Energy the force caused by the motion
  of an object.
• Potential Energy the force stored in an object
  that isnt moving.

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Lockout / Tagout

• Energy sources may include any one or combination
  of the following

• Electrical
• Mechanical
• Hydraulic
• Thermal/steam
• Gravitational
• All forms of potential stored energy

• Fluid under pressure/oil, water
• Gases
• Pneumatic
• Nuclear
• Chemical

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Lockout / Tagout

• Employees are to be trained in LO/TO procedures.
• Training must be done prior to participation in
  the program, and if a change occurs.
• Authorized Employee person who physically locks
  and tags equipment for maintenance or servicing.
• Affected Employee person who may operate or
  work in areas where equipment is subject to the
  LO/TO process.

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Lockout / Tagout

• Roles and responsibilities
• Authorized Employees involved in the lockout must
  be knowledgeable of the type and magnitude of the
  energy, the hazards of the energy to be
  controlled, and the method or means to control
  the energy before turning off equipment.

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Lockout / Tagout

• Authorized Employees will notify all Affected
  Employees (before and after) the LO/TO and the
  prohibition of attempts to restart or energize
  equipment.
• Equipment shall be turned off or shut down using
  the established procedures.

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Lockout / Tagout

• Lockout the equipment with a personal lock used
  by the Authorized Employee in charge.
• The tag placed on the equipment should be dated
  and signed by the person performing the work.

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Lockout / Tagout

• The Authorized Employee must affix lockout or
  tagout devices to each energy source or isolating
  device.
• The device shall be attached in a manner that
  will hold the energy isolating devices in a
  safe or off position.
• Turn the power source on to assure the power
  source has been deactivated.
• Always look for hidden energy sources.

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Lockout / Tagout

• No lock shall be affixed without a tag dated and
  signed by the person performing the isolation and
  stating the reason for the lockout.
• It is policy to use locks whenever possible. If
  this is not possible, a tag may be used.
• Tags must clearly state that movement of energy
  isolating devices from the safe or off
  position is prohibited.

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Lockout / Tagout

• Where tagout devices are used with devices that
  are capable of being locked, the tag attachment
  shall be fastened at the same point at which the
  lock would have been attached.
• Where a tag cannot be affixed directly to the
  energy isolating device, the tag shall be located
  as closely and safely as possible to the device.
• Guards and interlock devices cannot be used as a
  substitute for lockout devices.

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Lockout / Tagout

• Group Isolation When a crew or group performs
  service or maintenance, they must use a procedure
  that provides ALL employees a level of protection
  equal to that provided by a personal LO/TO
  device.
• Each employee attaches a personal LO/TO device
  to a group lockout mechanism.
• Each employee will test at the start station to
  ensure equipment is inoperable.

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Lockout / Tagout

• Every power source has its own procedure for
  lockout.
• The procedure may include
• Pulling a plug
• Opening a disconnect switch
• Removing a fuse
• Closing a valve
• Bleeding a line
• Placing a blind in a line

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Lockout / Tagout

• Always look for hidden energy sources, since some
  equipment has more than one power source.
• After ensuring that all personnel are clear, the
  equipment must be tested to verify that it is
  properly isolated and will not operate..

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Lockout / Tagout

• The following energy sources may be encountered
• Electrical
• motors controllers, capacitors, circuit breakers
• Pneumatic
• Hydraulic
• Fluids and gases
• Mechanical
• Blinding of Pipe

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Lockout / Tagout

• Restoring Power to Equipment
• Individual locks may be removed after each phase
  is complete by the Authorized Employee.
• Clear the work area of non-essential employees
  and equipment.
• Take a headcount to ensure all employees are
  clear.
• After removal of lock and tag devices, notify the
  Affected Employees.

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Lockout / Tagout

• Locking Tagging Device
• Each unit should provide standardized tags and
  individually keyed or combination locks as
  required to execute the LO/TO process.
• Tag devices must be of a non-reusable type,
  attachable by hand, self-locking.
• Critical systems locked and tagged should include
  identity and job title of person installing the
  lock and tag.

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MODULE 4REVIEW