Definition of Confined Space (NR‑33)

Characteristics: Limited Entry/Exit, Restricted Ventilation, Hazardous Potential

Importance of Confined Space Safety

Accident statistics and common causes

Regulatory overview: NR‑33 framework

Authorized Entrant

Attendant (Watchman)

Employer responsibilities

Communication and teamwork requirements

Atmospheric hazards

Oxygen deficiency and enrichment

Flammable gases and vapors

Toxic agents (H₂S, CO, solvents, vapors)

Physical hazards

Engulfment, entrapment, engulfing materials, and Mechanical, electrical, thermal risks

Noise, vibration, slips, falls and Biological hazards

Purpose of Atmospheric Testing

Types of detectors / Calibration and bump test

Testing sequence (O₂ → flammability → toxicity) / Continuous monitoring requirements

Interpretation of readings and alarm levels / Quiz – Atmospheric monitoring

Isolation of energy sources (LOTO)

Ventilation techniques / Purging and inerting

Barriers and signaling / Hot work precautions

Safe use of tools and equipment

Purpose of the entry permit / Required information (NR‑33 requirements)

Roles in permit authorization / Validity, cancellation, and records

Pre‑entry checklist

Respiratory protection: filters, SCBA, airline systems / Fall protection: harnesses, lifelines, tripods

Communication devices

Illumination and Intrinsically Safe Equipment / Maintenance and Inspection

Continuous monitoring of entrants / Prohibited behaviors for attendants

Communication methods / Warning signs and emergency triggers

Pre‑entry briefing / Work authorization

Step‑by‑step entry process / Monitoring during the activity

Documentation and reporting / End‑of‑work procedures

NR‑33 rescue requirements / Non‑entry vs. entry rescue

Duties of the attendant during emergencies / Use of retrieval systems

Understanding rescue plans (but NOT replacing rescue team training) / Coordination with emergency teams