CONFINED SPACE HAZARDS

1
CONFINED SPACE DEFINITION(OSHA 29 CFR 1910.146)

• AN ENCLOSED AREA THAT HAS FOLLOWING
  CHARACTERISTICS
• LARGE ENOUGH AND SO CONFIGURED THAT AN EMPLOYEE
  CAN BODILY ENTER AND PERFORM ASSIGNED WORK, AND
• ITS PRIMARY FUNCTION IS SOMETHING OTHER THAN
  HUMAN OCCUPANCY I.E. NOT DESIGNED FOR CONTINUOS
  HUMAN OCCUPANCY, AND
• HAS LIMITED OR RESTRICTED MEANS FOR ENTRY OR EXIT
• MAY CONTAIN POTENTIAL OR KNOWN HAZARDS
• FLAMMABLE GASES OR VAPOUR gt 10 OF LEL
• OXYGEN LEVEL lt19.5 OR gt23
• TOXIC GASES/ VAPOURS/ DUSTS gt PEL

2
CONFINED SPACE HAZARDS

• ATMOSPHERIC HAZARDS
• OXYGEN DEFICIENCY
• OXYGEN ENRICHED
• TOXIC OR IRRITATING ATMOSPHERE
• PHYSICAL HAZARDS
• FIXED PORTABLE MECHANICAL EQUIPMENT
• ELECTRICALLY ENERGIZED CONDUCTORS
• FLUIDS LIQUIDS, POWDERS GASES
• THERMAL CONDITION HOT OR COLD
• ENGULFMENT BY FINELY DEVIDED MATERIAL
• IONIZING AND NON-IONIZING RADIATION
• CONTACT WITH CORROSIVE SUBSTANCES

3
OXYGEN-DEFICIENT (lt19.5 ) OXYGEN-ENRICHED
(gt23.5 ) ATMOSPHERE

• CAUSES OF OXYGEN DEFICIENT CONDITIONS
• CONSUMED BY CHEMICAL REACTIONS LIKE OXIDATION
• CONSUMPTION DUE TO RUSTING OR CORROSION
• CONSUMPTION BY FERMENTATION OF ORGANIC MATTER
• OXYGEN DISPLACEMENT BY NITROGEN OR INERT GAS
• ADSORPTION BY CARBON OR CHARCOAL
• CAUSES OF OXYGEN ENRICHED CONDITIONS
• LEAK THROUGH OXYGEN USAGE LINE
• COMPRESSED O2 USED TO DISLODGE WELDING SLAG
• LEAKING OXYGEN TUBING FROM CUTTING TORCH

4
FLAMMABLE ATMOSPHERE

• FLAMMABLE GASES AND VAPOURS
• FLASH POINT, FIRE POINT AND IGNITION POINT
• FLAMMABLE LIMITS LEL UEL
• IGNITION ENERGY
• VAPOUR DENSITY
• EFFECTS OF TEMPERATURE PRESSURE ON FLAMMABILITY
• COMBUSTIBLE DUSTS
• IGNITION SENSITIVITY
• IGNITION TEMPERATURE
• IGNITION ENERGY

5
SOURCES OF IGNITION

• OPEN FLAMES
• ELECTRICAL ARCING
• FRICTIONAL SPARKS
• HOT SURFACES
• STATIC ELECTRICITY
• CHEMICAL REACTIONS
• USE OF NON FLAMEPROOF ELECTRICAL EQUIPMENT

6
CONTROL OF IGNITION HAZARDS

• NON-SPARKING TOOLS
• APPROVED ELECTRICAL EQUIPMENT
• INTRINSICALLY SAFE EQUIPMENT
• EXPLOSION PROOF EQUIPMENT
• SPECIAL HOT WORK PRECAUTIONS
• VESSEL INERTING FOR EXTERIOR HOTWORK
• GAS CUTTING TORCHES AND THEIR VALVES
• HOSES AND REGULATORS
• COMPRESSED GAS CYLINDERS
• FIRE PREVENTION PROTECTION

7
TOXIC ATMOSPHERES(GAS, DUST, FUME, MIST
VAPOURS)

• ASSESSING TOXIC ATMOSPHERES
• PREVIOUS CONTENTS
• POSSIBLE CHEMICAL REACTIONS
• OPERATIONS PERFORMED EX. SOLVENT CLEANING,
  PAINTING, DEGREASING, WELDING, BLASTING ETC.
• TOXICOLOGICAL PRINCIPLES
• TOXICITY VS HAZARDS
• DOSE RESPONSE
• LOCAL VS SYSTEMIC EFFECT
• ACUTE VS CRONIC EXPOSURES EFFECTS
• EXPOSURE STANDARDS
• THRESHOLD LIMIT VALUES (TLVs)
• TIME WEIGHTED AVERAGES (TWAs)
• STEL, CEILING CONCENTRATIONS IDLH

8
VESSEL ENTRY PROGRAM REQUIREMENT

• HAZARD IDENTIFICATION
• CHARACTERISTICS OF THE SPACE
• ATMOSPHERIC HAZARDS
• PHYSICAL HAZARDS
• OTHER CONSIDERATIONS
• DETERMINING THE REASON FOR ENTRY
• PHYSICAL CHARACTERISTIC SURVEY
• SIZE AND CONFIGURATION
• SPACE MOBILITY
• ATTACHED EQUIPMENT
• LIGHTING
• PREVIOUS CONTENTS
• DETERMINE OPERATIONS TO BE PERFORMED
• VISUAL INSPECTION

9
VESSEL ENTRY PROGRAM REQUIREMENT

• HAZARD CONTROL
• RANKING HAZARDS
• HAZARD SEVERITY
• PROBABILITY OF OCCURRENCE
• HAZARD ASSESSMENT
• GENERAL CONTROL STRATEGIES
• CONTROL OF UNAUTHORIZED ENTRY
• EXTERNAL HAZARD PROTECTION
• DRAINING AND FLUSHING TO REMOVE RESIDUE
• LOCKOUT-TAGOUT PROCEDURES
• DISCONNECTING AND BLANKING LINES
• PURGING AND VENTING
• PROTECTIVE EQUIPMENT

10
VESSEL ENTRY PROGRAM REQUIREMENT

• ENTRY PERMIT SYSTEM
• PERMIT ELEMENTS
• IDENTIFICATION JOB DESCRIPTION
• DESCRIPTION OF THE HAZARD
• PRECAUTIONS ALREADY TAKEN WHILE PREPARATION
• ISOLATIONS
• GAS TEST RESULTS
• COMMUNICATIONS
• SPECIAL EQUIPMENT OR PRECAUTIONS
• IDENTIFY ENTRANTS AND STAND BY RESCUE
• HOTWORK PERMIT INVOLVED
• ANY OTHER RELEVANT INFORMATION
• ISSUE, AUTHORIZATION AND ACCEPTANCE
• COMPETING THE PERMIT PROCEDURE

11
VESSEL ENTRY PROGRAM REQUIREMENT

• SPECIALIZED EQUIPMENT
• AIR MONITORING INSTRUMENTS
• VENTILATION EQUIPMENT
• PERSONAL PROTECTIVE GEAR
• PORTABLE EXPLOSION PROOF LIGHTING
• COMMUNICATION EQUIPMENT
• PROTECTIVE BARRIERS AND SHIELDS
• LADDERS AND CLIMBING DEVICES
• EMERGENCY AND RESCUE EQUIPMENT

12
VESSEL ENTRY PROGRAM REQUIREMENT

• TESTING AND MONITORING
• INSTRUMENTS CALIBRATION
• SAMPLING STRATEGIES
• EMPLOYEE DESIGNATED, DEFINED DUTIES
  RESPONSIBILITY
• AUTHORIZED ISSUER
• SUPERVISORS
• ENTRANTS
• ATTENDANTS
• EMERGENCY RESCUER
• CO-ORDINATING CONTRACTORS ENTRY
• EMPLOYEES RESPONSIBILITIES
• CONTRACTORS RESPONSIBILITIES
• EMERGENCY RESPONSE PROCEDURES

13
VESSEL ENTRY PROGRAM REQUIREMENT

• VENTILATING CONFINED SPACES
• DIFFERENCE BETWEEN VENTILATION PURGING
• GENERAL VENTILATION
• LOCAL EXHAUST
• VENTILATION EQUIPMENT
• VENTILATION PLANNING CONSIDERATIONS
• OPENINGS
• INTERNAL OBSTRUCTIONS
• VAPOUR DENSITY
• SHORT CIRCUITING
• SUPPLYING VS EXHAUSTING
• OPERATIONS IN THE SPACE

14
Confined space entry system