Confined space Safety and
13 Confined space hazards
- Fire Hazard:- Fire hazard in confined space due to welding, soldering, Cutting, Drilling Grinding Sparks / Arcs or Open-flames.
- Slip & trip Hazard: Slip, trip due to uneven surface, Hazards like Entrapment/Engulfment/ Snagging or impacts.
- Space configured inwardly Converging walls, slopped/ tapered floors could trap or asphyxiate
- Fall of person in confined space or Unauthorized entry into confined space after manhole is opened.
- Unconsciousness of person (s) entering in Vessel/ CS due to oxygen deficiency/toxic gas inhalation.
- Asphyxiation due to oxygen deficiency due to accidental discharge of inert gas from fire protection system.
- Toxic air contaminants or gas / Fumes/ dusts/ vapors like CO,H2S in confined space/vessel in excess of 50% PEL /IDLH. Toxic/ Combustible contamination / residues form adjoining plants transfer inside confined space/vessel.
- Body part engulfment or entrapping in rotating/ agitation or other power driven equipment, moving parts or machinery.
- Asphyxiation due to oxygen deficiency because of rusting process/ chemical process which takes place in vessel/ confined space(CS) or vessel/ CS was inserted with Nitrogen / CO2 or with other gas for fire Blanketing in its normal service.
- Asphyxiation due to oxygen deficiency because of entry of other gases/ vapours/ Fumes/ chemicals / form adjoining plant process, rector/ vessel/ pipe/dust etc.
- Asphyxiation due to oxygen deficiency while work is in progress in confined space due to gas leak from connection/hoses of gas cylinders like ar/n acetylene in the space or generation of gases because of work (like hot work which be carried) in CS which will dilute/replace available oxygen.
- Asphyxiation due to Oxygen deficiency due to consumption of available oxygen due to work (like hot work) supposed to be carried out in CS.
- Electrocution due to electrical gadgets like lamps, tools exposed conductor of welding cable/electrode holder used in confined space/vessel.
Confined space hazards and control PDF
6 PPE & Specialized Equipment and Confined space requirements
- SABA/SCBA with full face mask.
- Helmets / Ear plugs / Dust Mask.
- Safety /Goggles/ Chemical splash protection / goggles/ Face- shields.
- Chemical Splash protection full Body Suit/ Boiler Suit /Full Body Overhaul.
- Chemical/ Temperature /Abrasion / Rubber/ Gloves.
- Air -purifying Respirators with Full/ Half Face Mask.
9 Confined space Specialized Equipment requirements
- First Aid Kit
- Fire Extinguishers
- Portable Electric Devices/ Lighting of 12 volts or 120/215 volts if only protected with RCD/ELCB.
- Emergency Shower.
- Explosion Proof Lighting / Torch (es)
- Spark resistant tool
- Lifting/ Tripod/ Hoisting >5 in Rescue Equipment.
- Rescue stretcher.
5 confined space Special Instructions and Precautions.
- Emergency Rescue plan reviewed with WG Team.
- Toolbox talk based on JSA to WG.
- Specialized Training for WG.
- Use only Intrinsically safe/ Explosion proof/ non- sparking equipment/ tools.
- Hard Barricading to prevent unauthorized entry into work area.
15 Control Measure & Safety Preparations & Precautions.
- Vessel/ confined space is positively isolated from all process systems by physical disconnection, blinding by approved method as prescribed in CSE standard/ PTW procedure.
- Vessel depressurized, drained of its content, flushed with water/ steam, decontaminated completely, ventilated adequately, continuously purged with fresh air till Confined space Oxygen level in more than 19.5% than 23.5%.
- Gas cylinders are kept outside confined space/ vessel. All connections of cutting torches and flexible hose pipes of gas cutting set are checked for leakage and found OK.
- Confined space/ vessel continuously purged with fresh air and oxygen level is measured continuously or at least once an hour level is ensured more than 19.5% than 23.5%.
- After oxygen availability test, it is ensured that CO is less than 10 ppm, H2S is less than 10 ppm and LEL is less than 10%. All tests are carried out by Authorized Gas Tester
- Respiratory protection supplied Air Breathing Apparatus (SABA)/ Self Contained Breathing Apparatus (SCBA) is provided as air/atmosphere can not be brought within safe limits.
- Physical disconnection/ de-energized the motor/ prime mover/driver by removing the belts or if direct coupled, removing the coupling and Energy/power Supply source and LOTOTO is done.
- Ensured that all Portable Electrical Equipment taken into confined space of 12 volts maximum or if 120/215 volts, then are protected by RCD/ELCB.
- Ensured that entrants are allowed to enter inside vessel with full body harness with one end of life Line with Attendant (s) at manhole.
- Stored energy (electrical inductor/ fan-blades, rotors, capacitors, pneumatics, Hydraulics) completely de-energized to zero energy state and LOTOTO is done.
- Confined Space opening / Area is barricaded with hard Barriers, Safety signs are posted.
- Job Specific Emergency rescue plan is prepared, reviewed and emergency equipment/ trained rescuer are ready for rescue.
- Job safety Analysis is done by PA by AO.
- Training imparted to the attendant on role and responsibility.
- Training imparted to entrants on roles and responsibility.
- Ensure all Confined space safety Available
Types of confined spaces
Confined space entry procedure
Basic Steps of the Confined space job Entering the Tank for Decaling activity by man Basket.
Hazards associated with the step Caustic spillage may happen due to improper positive isolation.
Can cause skin and eye irritation. in extreme cases cause server burns and eye damage or blindness
Existing control Measures to mitigate hazards
- All positive isolation points are witness by the team members comprising of AO,PA and WG before man entry (attached P &ID and simplified PFD)
- Proof of isolation are attached and reviewed.
- Isolation document is verified, reviewed and approved by the concern authority.
Hazard due to temperature
Causing illnesses such as heat cramps and heat stroke.
Can cause bodily injuries
- All of the inspection door, cleaning door are opened and force ventilation is ensured at least for 8 hrs. Before entering.
- Fresh air supply to inside the Tank is available.
- Check temperature from outside by pyrometer and to confirm it is not above room temperature.
Hazard due to poor illumination
Can cause eye discomfort or headache.
- 24 volt light are provided for illumination inside the Tank.
- Head light also provide to working crew.
Exposure toxic and poisonous gases
Possibility of shortness of breath, wheezing, fatigue, respiratory problems
- Multi gas tester is used for testing at minimum 3 level -top, middle and bottom by AGT.
- Ensure no toxic or poisonous gases.
- Informed to Rescue team to alert during the period of Descaling.
- Emergency contact number and communication flow chart is maintained prior to Job start.
Inhalation of vapors, dust.
Possibility of sneezing, coughing, eye irritation, lung tissue swelling, asthma and throat infections.
- Nose mask is used before entering into the Tank.
- Confined space passes issued to the manpower with no respiratory disorder as per confined space guideline.
Suffocation due to oxygen deficiency
Can cause vertigo, headache, speech difficulties and suffocation
- Oxygen level checked by AGT before entering and ensured it should not be <19.5%.
- Attendant with entry/exit register is maintained.
- During descaling O2 analyzer is used on continuous basis.
- Deployed distress bell to alert the attendant.
- Rescue team kept in loop through out the job period.
Oxygen Enrichment chances of fire explosion
Chance of fire explosion
- Oxygen level checked by AGT before entering and ensured it should not be >23.5%
- During descaling O2 Analyser is used on continuous basis.
- Fire extinguisher kept in place.
- Rescue team kept in loop.
Confined space class abc
Confined space class OSHA
Working in confined spaces
Working area inspection
Slip,trip and falls during working area inspection
Can cause bodily injuries
- Ensure Area housekeeping.
- Identify nearest safety shower and ensure working condition.
- Restriction of other activities like maintenance job or machinery movement.
Spillage of liquor from near by pipe line or valve gland.
Can cause skin and eye irritation. In extreme cases cause server burns and eye damage or blindness.
- Use mono goggles, caustic Suite before entry to operational area premises.
- Area has to be barricaded. If found any abnormal inform to concern authority.
- Carry diphoterine solution.
Fall of person from height while climbing on the Tank top by stair case.
Can cause bodily injuries
- Stair case is available with standard toe gaurd and hand rail.
- Schedule inspection is implemented for stair case and grating plate.
Confined space Fall hazard during physical inspection from tank top inspection hatch.
- Personnel wear safety harness and tie to external support during physical inspection from hatch.
- Skilled manpower are deployed to execute the task.
- Ensure Tank level by conducting Ball test.