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🚧 Confined Space Program

OSHA's confined space standard (29 CFR 1926 Subpart AA) requires comprehensive programs to protect workers entering confined spaces. This guide helps you comply.

What is a Confined Space?​

Confined space has three characteristics:

  1. Large enough to enter and work
  2. Limited entry/exit - Not designed for continuous occupancy
  3. Not designed for continuous worker occupancy

Examples:

  • Manholes
  • Tanks
  • Vessels
  • Silos
  • Pits
  • Tunnels
  • Ductwork
  • Boilers

Permit-Required Confined Space (PRCS)​

Permit-required confined space has one or more of these characteristics:

  1. Hazardous atmosphere - Flammable, toxic, oxygen-deficient
  2. Engulfment hazard - Material that could engulf entrant
  3. Configuration hazard - Inwardly converging walls or sloping floor
  4. Other serious hazards - Mechanical, electrical, or other hazards

OSHA requires: Written permit program before entry.

Required Program Elements​

1. Written Program​

Your program must include:

  • Identification - Identify all confined spaces
  • Evaluation - Evaluate hazards
  • Entry procedures - Safe entry procedures
  • Permit system - Permit-required spaces
  • Training - Employee training
  • Equipment - Required equipment
  • Rescue - Rescue procedures

2. Confined Space Identification​

Survey your worksite:

  • Identify all spaces - List all confined spaces
  • Evaluate hazards - Determine if permit-required
  • Mark spaces - Post warning signs
  • Document - Keep inventory

Common construction confined spaces:

  • Manholes (sewer, electrical, telecommunications)
  • Tanks (water, chemical, storage)
  • Vessels (pressure vessels, boilers)
  • Excavations (deep, narrow)
  • Silos and bins
  • Ductwork and tunnels

3. Hazard Evaluation​

Evaluate each space for:

Atmospheric hazards:

  • Oxygen deficiency - under 19.5% oxygen
  • Oxygen enrichment - over 23.5% oxygen
  • Flammable gases - over 10% LEL
  • Toxic gases - Above PEL

Physical hazards:

  • Engulfment - Loose material
  • Mechanical - Moving parts
  • Electrical - Live circuits
  • Temperature - Extreme heat/cold
  • Configuration - Narrow passages

4. Entry Permit System​

For permit-required spaces:

Permit must include:

  • Space identification - Location, description
  • Purpose of entry - Why entering
  • Date and duration - Entry period
  • Authorized entrants - Who can enter
  • Attendant - Standby person
  • Entry supervisor - Person authorizing entry
  • Hazards - Known hazards
  • Control measures - How hazards controlled
  • Acceptable conditions - Entry conditions
  • Test results - Atmospheric testing
  • Rescue - Rescue procedures
  • Equipment - Required equipment

Permit duration: Valid for one shift or until conditions change.

5. Atmospheric Testing​

Test before entry:

  • Oxygen - 19.5% to 23.5%
  • Flammable gases - under 10% LEL
  • Toxic gases - Below PEL

Testing order:

  1. Oxygen first - Oxygen deficiency kills fastest
  2. Flammable gases - Explosion risk
  3. Toxic gases - Poisoning risk

Continuous monitoring: Required during entry.

6. Entry Procedures​

Before entry:

  • Permit issued - Valid permit
  • Atmosphere tested - Acceptable conditions
  • Ventilation - If needed
  • Isolation - Lockout/tagout
  • Equipment ready - All equipment available
  • Rescue ready - Rescue team available
  • Communication - Test communication

During entry:

  • Attendant present - Standby person outside
  • Continuous monitoring - Monitor atmosphere
  • Communication - Maintain contact
  • No smoking - No ignition sources

7. Roles and Responsibilities​

Authorized Entrant​

Duties:

  • Know hazards - Understand space hazards
  • Use equipment - Proper use of PPE
  • Communicate - Alert attendant of problems
  • Exit immediately - If ordered or alarm sounds

Training required: Before first entry, annually, when hazards change.

Attendant​

Duties:

  • Monitor entrants - Know who's inside
  • Stay outside - Remain at entry point
  • Monitor conditions - Watch for hazards
  • Communicate - Maintain contact with entrants
  • Order evacuation - If conditions unsafe
  • Summon rescue - Call rescue if needed
  • Prevent unauthorized entry - Keep unauthorized out

Training required: Before first assignment, annually, when hazards change.

Entry Supervisor​

Duties:

  • Issue permit - Authorize entry
  • Verify conditions - Ensure safe conditions
  • Cancel permit - If conditions change
  • Verify rescue - Ensure rescue available

Training required: Before first assignment, annually, when hazards change.

8. Equipment Requirements​

Required equipment:

  • Atmospheric monitor - Multi-gas detector
  • Ventilation - If needed
  • Lighting - Adequate lighting
  • Communication - Two-way communication
  • Retrieval equipment - Harness, lifeline
  • PPE - Appropriate PPE
  • Rescue equipment - If rescue required

Inspection: Inspect before each use.

9. Ventilation​

When required:

  • Hazardous atmosphere present
  • Cannot eliminate hazards
  • To maintain safe conditions

Types:

  • Mechanical ventilation - Fans, blowers
  • Natural ventilation - Openings, wind

Requirements:

  • Adequate flow - Sufficient air movement
  • Test after ventilation - Verify conditions
  • Continuous - Maintain during entry

10. Isolation (Lockout/Tagout)​

Isolate hazards:

  • Energy sources - Electrical, mechanical, hydraulic
  • Pipes/lines - Blank or disconnect
  • Valves - Lock closed
  • Verify isolation - Test before entry

Lockout/tagout required per 29 CFR 1926.417.

11. Rescue Procedures​

Rescue options:

Non-entry rescue:

  • Retrieval equipment
  • Attendant pulls entrant out
  • No entry required

Entry rescue:

  • Trained rescue team enters
  • Must be trained and equipped
  • Must practice annually

External rescue:

  • Local fire department
  • Must be notified
  • Must be available

Requirements:

  • Rescue available - Team ready
  • Equipment ready - Rescue equipment available
  • Practice - Annual practice required
  • Communication - Contact information

12. Training​

Required training:

Authorized entrants:

  • Hazards - Space hazards
  • Symptoms - Exposure symptoms
  • Equipment - Use of equipment
  • Communication - Communication procedures
  • Self-rescue - How to self-rescue

Attendants:

  • Hazards - Space hazards
  • Monitoring - How to monitor
  • Communication - Communication procedures
  • Evacuation - When to order evacuation
  • Rescue - How to summon rescue

Entry supervisors:

  • Hazards - Space hazards
  • Permit system - How to use permits
  • Verification - How to verify conditions
  • Cancellation - When to cancel permits

Frequency: Before first assignment, annually, when hazards change.

Common Confined Space Scenarios​

Manhole Entry​

Hazards:

  • Oxygen deficiency
  • Toxic gases (H2S, methane)
  • Engulfment (water, debris)
  • Traffic (if in roadway)

Controls:

  • Test atmosphere - Before entry
  • Ventilate - If needed
  • Traffic control - Barricades, signs
  • Retrieval equipment - Harness, lifeline
  • Attendant - Standby person

Tank Entry​

Hazards:

  • Oxygen deficiency
  • Toxic vapors
  • Flammable vapors
  • Engulfment (liquid, sludge)

Controls:

  • Empty and clean - Remove contents
  • Ventilate - Continuous ventilation
  • Test atmosphere - Before and during entry
  • Isolate - Lockout valves, lines
  • Rescue ready - Rescue team available

Recordkeeping​

Required Records​

  • Written program - Keep current
  • Permits - Keep for 1 year
  • Training records - Keep duration of employment
  • Test results - Atmospheric testing records

Penalties for Non-Compliance​

ViolationTypical Penalty
Serious$16,131 per violation
Willful$161,323 per violation
Repeat$161,323 per violation

Best Practices​

  1. Identify all spaces - Complete survey
  2. Evaluate hazards - Thorough evaluation
  3. Train everyone - All involved personnel
  4. Test atmosphere - Before every entry
  5. Have rescue ready - Before entry
  6. Document everything - Keep records
Deadly Hazard

Confined spaces kill workers every year. Never enter a confined space without proper training, testing, and rescue procedures. When in doubt, don't enter.