Confined Space Safety Training

Confined Space

• A confined space is large enough to enter, but may have limited means of entry and exit
• A confined space is not designed for continuous occupancy

Examples of Confined Spaces

• Tanks
• Vessels
• Sewers
• Manholes
• Silos
• Trenches
• Vaults

Common Accidents in Confined Spaces

• Suffocation due to lack of oxygen
• Explosion due to flammable gases present
• Poisoning from toxic materials
• Engulfment in liquids or solids
• Injuries from falls
• Electrocution

Why Confined Space Training is Necessary

• To learn about the hazards present in confined spaces
• To develop safe work practices for entering and working in confined spaces
• To know how to respond to emergencies

Signs of Confined Space

• Warning Signs: "Confined Space - Authorized Personnel Only"
• Safety Equipment: Respirators, air monitoring equipment, safety harnesses, communication devices
• Emergency Plans: Emergency contact information, rescue procedures

Confined Space Hazards

• Atmospheric Hazards:
  • Oxygen deficiency
  • Oxygen-enriched atmospheres
  • Flammable/combustible gases and vapors
  • Toxic gases and chemicals
  • Oxygen Deficiency:
    • Caused by burning, oxidation, decomposition, displacement
  • Oxygen-Enriched Atmospheres:
    • Can cause rapid combustion
    • Can cause oxygen toxicity
  • Flammable Atmospheres:
    • Require flammable material, oxygen, ignition source
    • LFL (Lower Flammable Limit)
    • UFL (Upper Flammable Limit)
  • Toxic Atmosphere:
    • Caused by storage, improper isolation, work performed in confined space
    • Common Toxic Chemicals: VOC, H2S, CO, HCl, NO2
    • VOC: Heavier than air, toxic and flammable at low concentrations
    • Hydrogen Sulfide (H2S): Heavier than air, rotten egg odor at low concentrations, can be fatal at high concentrations
    • Nitrogen Dioxide (NO2): Toxic diesel emissions, yellowish-brown gas, irritant to the lungs
    • Carbon Monoxide (CO): Odorless, colorless combustion byproduct, can quickly cause death at high concentrations
• Physical Hazards:
  • Engulfment in solid or liquid
  • Extreme temperatures
  • Insufficient lighting
  • Noise
  • Wet surfaces
  • Falling objects
  • Engulfment:
    • Can cause death by plugging respiratory system or pressure on body
  • Extreme Temperatures:
    • Risk of heatstroke and heat stress
    • Risk increases due to PPE and lack of ventilation
  • Noise:
    • Amplified in confined spaces, can damage hearing and affect communication
  • Wet Surfaces:
    • Increased risk of slips, falls, and electrocution
  • Insufficient Lighting:
    • Provide emergency lighting and explosion proof lighting
  • Falling Objects:
    • Workers are exposed to falling objects from topside openings
• Mechanical Hazards:
  • Configuration of confined space
  • Grinding, crushing, or mixing mechanisms

Hierarchy of Safety for Confined Space Work

• Eliminate: Avoid entering confined spaces if possible
• Prevent: Develop and implement a safe system of work
• Control: Devise emergency plan

Confined Space Elimination

• Modify work to be done from outside the confined space if possible.

Confined Space Prevention

• Safe System of Work:
  • Appoint a competent person to carry out risk assessment, recommend safety precautions and develop a safe system of work
  • Check List: Appoint suitable person for work, isolate the confined space, clean and cool before entry, check the size of entrance, test the air, provide ventilation, provide special tools and lighting, provide PPE
• Ventilation:
  • Remove contaminants that are heavier than air (e.g., H2S)
  • Remove contaminants that are lighter than air (e.g., CO)
• Purge Time: Time required to remove contaminants from a confined space using a blower.
  • Purge Time Formula: T = 7.5 V/C
    • T = Purge time in minutes
    • V = Volume of the space in ft³
    • C = Effective blower capacity ft³/min
• Testing Confined Space:
  • Duration: Test regularly while in the confined space
  • Testing Order: Test for oxygen first, then combustible gases, then toxic gases and vapors
  • Sampling: Samples of air should be taken in layers to ensure accurate testing
  • Documentation: Always document all testing results
• Emergency Exit Plan:
  • Communication: Establish clear methods of communication between workers inside and outside the confined space
  • Shutdown: Procedure for shutting down operations in the event of an emergency
  • First Aid Procedures: Emergency first aid procedures for workers inside the confined space
  • Drill: Regular practice drills of the emergency exit plan
  • Emergency Services: Contact information for emergency rescue services

Types of Confined Spaces

• Non-Permit: Confined spaces that do not require a permit for entry, because there are no hazards present
• Permit Required Entry: Confined spaces that require a permit before entry due to the presence of hazards

Confined Space Permit

• Purpose of Entry: Clearly state the purpose of entry
• Work Time: How much time will the work take?
• Authorized Personnel: Who is authorized to enter the space?
• Attendant: Who will be the attendant outside the confined space?
• Atmospheric Conditions: What are the atmospheric conditions in the confined space?
• Communication: How will workers inside the confined space communicate with those outside?
• Equipment: What equipment is being provided for safe entry?
• Additional Check Lists: Are there any additional safety checklists?
• Hazard Elimination: How have the hazards been eliminated?

Duties of Attendants

• Know the hazards of the confined space
• Maintain an accurate count of workers inside
• Remain outside the confined space until relieved by another attendant
• Maintain regular communication with workers inside the confined space
• Monitor conditions inside and outside the confined space
• Summon rescue services when needed
• Ensure unauthorized personnel do not enter the confined space
• Perform non-entry rescues
• Do not perform any other duties that might interfere with their primary duty to monitor and protect the workers

Get Out!

• If any worker encounters a hazard inside a confined space, they should:
  • Stop all activities
  • Exit the confined space immediately
  • Evaluate the hazard
  • Implement protective measures

Always Remember

• Test the atmosphere prior to entry and at regular intervals
• Never enter a confined space if the atmospheric conditions are not suitable
• Always have an attendant outside the confined space
• Follow company confined space permit procedures