confined space entry construction industry standard 1926.21(b)(6) construction industry standard...

Confined Space EntryConfined Space Entry

• Construction Industry Standard Construction Industry Standard 1926.21(b)(6)1926.21(b)(6)

• General Industry StandardGeneral Industry Standard1910.1461910.146

• Best Practices for all IndustriesBest Practices for all Industries

Construction Industry StandardConstruction Industry Standard

All employees required to enter into All employees required to enter into confined or enclosed spaces shall be confined or enclosed spaces shall be instructed as to the nature of the hazards instructed as to the nature of the hazards involved, the necessary precautions to be involved, the necessary precautions to be taken, and in the use of protective and taken, and in the use of protective and emergency equipment required. The emergency equipment required. The employer shall comply with any specific employer shall comply with any specific regulations that apply to work in dangerous regulations that apply to work in dangerous or potentially dangerous areas.or potentially dangerous areas.

Typical Confined SpacesTypical Confined Spaces

• Boiler, Degreaser, FurnaceBoiler, Degreaser, Furnace• Pipeline, Pit, Pipeline, Pit, Pumping StationPumping Station• Reaction or Process Vessel, MillsReaction or Process Vessel, Mills• Septic Tank, Sewage DigestorSeptic Tank, Sewage Digestor• Silo, Storage Tank, BargesSilo, Storage Tank, Barges• Sewer, Utility Vault, ManholeSewer, Utility Vault, Manhole• Trenches, Shafts, CaissonsTrenches, Shafts, Caissons

How to Identify Confined SpacesHow to Identify Confined Spaces

• Limited Openings for Entry and ExitLimited Openings for Entry and Exit

• Unfavorable Natural VentilationUnfavorable Natural Ventilation

• Not Designed for Continuous Worker Not Designed for Continuous Worker OccupancyOccupancy

Categorizing Work SpaceCategorizing Work Space

* Space large enough to enter &;* Limited or Restricted entry or exit &;* Not designed for continuous worker occupancy.

NONot a confined Space

YES Confined Space

Hazardous Atmosphere

Engulfment Hazard

Configuration Hazard

Any other recognized serious hazard

Permit-

Required

Confined

Space

Non

Permit

Required

Space

YES NO

Or

Or

Or

Limited Openings for Entry/ExitLimited Openings for Entry/Exit

• Openings as small as 18 inches in diameter.Openings as small as 18 inches in diameter.• Difficult to enter with SCBA or other life-Difficult to enter with SCBA or other life-

saving equipment.saving equipment.• Difficult to remove downed worker in Difficult to remove downed worker in

folded up or bent over position.folded up or bent over position.• Exit from large openings may be difficult Exit from large openings may be difficult

due to presence of ladders, hoists, etc.due to presence of ladders, hoists, etc.

Unfavorable Natural VentilationUnfavorable Natural Ventilation

• Lack of air movement in and out of the space Lack of air movement in and out of the space can create an atmosphere much different can create an atmosphere much different than the outside atmosphere.than the outside atmosphere.

• Deadly gases can be trapped inside.Deadly gases can be trapped inside.• Organic materials can decompose.Organic materials can decompose.• May not be enough oxygen due to presence May not be enough oxygen due to presence

of other gases or chemical reactions such as of other gases or chemical reactions such as rusting.rusting.

Not Designed for Continuous Not Designed for Continuous Worker OccupancyWorker Occupancy

• Most confined spaces are not designed to Most confined spaces are not designed to enter and work in on a regular basis.enter and work in on a regular basis.

• Designed to store a product.Designed to store a product.• Enclose materials or processes.Enclose materials or processes.• Transport products or substances.Transport products or substances.• Occasional worker entry for inspection, Occasional worker entry for inspection,

repair, cleanup, maintenance, etc.repair, cleanup, maintenance, etc.

Dangerous CombinationsDangerous Combinations

• Presence of all three confined space Presence of all three confined space characteristics can complicate the situation.characteristics can complicate the situation.

• Working in and around the space.Working in and around the space.• Rescue operations during emergencies.Rescue operations during emergencies.• Worsened conditions due to work activities:Worsened conditions due to work activities:

– Welding and cutting, use of bonding agentsWelding and cutting, use of bonding agents– Cleaning with solvents, use of other chemicalsCleaning with solvents, use of other chemicals– Use of gas-powered equipmentUse of gas-powered equipment

Hazards of Confined SpacesHazards of Confined Spaces

• Oxygen Deficient AtmospheresOxygen Deficient Atmospheres• Oxygen Enriched AtmospheresOxygen Enriched Atmospheres• Flammable AtmospheresFlammable Atmospheres• Toxic AtmospheresToxic Atmospheres• Temperature ExtremesTemperature Extremes• Engulfment HazardsEngulfment Hazards• Noise, Slick/Wet Surfaces, Falling ObjectsNoise, Slick/Wet Surfaces, Falling Objects

Oxygen Deficient AtmospheresOxygen Deficient Atmospheres

19.5 %19.5 % Minimum acceptable oxygen level.Minimum acceptable oxygen level.

15 - 19%15 - 19% Decreased ability to work strenuously.Decreased ability to work strenuously.Impair coordination. Early symptoms.Impair coordination. Early symptoms.

12-14%12-14% Respiration increases. Poor judgment.Respiration increases. Poor judgment.

10-12%10-12% Respiration increases. Lips blue.Respiration increases. Lips blue.

8-10%8-10% Mental failure. Fainting. NauseaMental failure. Fainting. NauseaUnconsciousness. Vomiting.Unconsciousness. Vomiting.

6-8%6-8% 8 minutes - fatal, 6 minutes - 50% fatal8 minutes - fatal, 6 minutes - 50% fatal4-5 minutes - possible recovery.4-5 minutes - possible recovery.

4-6%4-6% Coma in 40 seconds. DeathComa in 40 seconds. Death

Oxygen Enriched AtmospheresOxygen Enriched Atmospheres

• Oxygen level above 21%.Oxygen level above 21%.• Causes flammable and combustible materials Causes flammable and combustible materials

to burn violently when ignited.to burn violently when ignited.• Hair, clothing, materials, etc.Hair, clothing, materials, etc.• Oil soaked clothing and materials.Oil soaked clothing and materials.• Never use pure oxygen to ventilate.Never use pure oxygen to ventilate.• Never store or place compressed tanks in a Never store or place compressed tanks in a

confined space.confined space.

Flammable AtmospheresFlammable Atmospheres

• 2 Critical Factors:2 Critical Factors:– Oxygen content in the air.Oxygen content in the air.– Presence of a flammable gas, or vaporPresence of a flammable gas, or vapor– Presence of dust (visibility of 5’ or less)Presence of dust (visibility of 5’ or less)

• Proper air/gas mixture can lead to explosionProper air/gas mixture can lead to explosion• Typical Ignition Sources:Typical Ignition Sources:

– Sparking or electric tool.Sparking or electric tool.– Welding / cutting operations.Welding / cutting operations.– SmokingSmoking

Toxic AtmospheresToxic Atmospheres

• Product stored in a confined space:Product stored in a confined space:» Gases released when cleaning.Gases released when cleaning.

» Materials absorbed into walls of confined space.Materials absorbed into walls of confined space.

» Decomposition of materials in the confined space.Decomposition of materials in the confined space.

• Work performed in a confined space:Work performed in a confined space:» Welding, cutting, brazing, soldering.Welding, cutting, brazing, soldering.

» Painting, scraping, sanding, degreasing.Painting, scraping, sanding, degreasing.

» Sealing, bonding, melting.Sealing, bonding, melting.

• Areas adjacent to a confined space.Areas adjacent to a confined space.

Hydrogen SulfideHydrogen Sulfide

• Decomposition of materials. Human waste.Decomposition of materials. Human waste.• Rotten egg odor at low concentrations.Rotten egg odor at low concentrations.• Possibly no warning at high concentrations.Possibly no warning at high concentrations.

PPMPPM EffectEffect TimeTime10 ppm10 ppm Permissible Exposure LevelPermissible Exposure Level 8 Hours8 Hours

50 - 10050 - 100 Mild Irritation - eyes, throatMild Irritation - eyes, throat 1 Hour1 Hour

200 - 300200 - 300 Significant IrritationSignificant Irritation 1 Hour1 Hour

500 -700500 -700 Unconsciousness, DeathUnconsciousness, Death 1/2 - 1 Hour1/2 - 1 Hour

>1000>1000 Unconsciousness, DeathUnconsciousness, Death MinutesMinutes

Carbon MonoxideCarbon Monoxide

• Odorless, Colorless Gas.Odorless, Colorless Gas.

• Combustion By-Product.Combustion By-Product.

• Quickly collapse at high concentrations.Quickly collapse at high concentrations.

PPMPPM EffectEffect TimeTime 5050 Permissible Exposure LevelPermissible Exposure Level 8 Hours8 Hours

200200 Slight headache, discomfortSlight headache, discomfort 3 Hours3 Hours

600600 Headache, discomfortHeadache, discomfort 1 Hour1 Hour

1000-20001000-2000 Confusion, nausea, headacheConfusion, nausea, headache 2 Hours2 Hours

1000-20001000-2000 Tendency to staggerTendency to stagger 1 1/2 Hours1 1/2 Hours

1000-20001000-2000 Slight heart palpitationSlight heart palpitation 30 Min.30 Min.

2000-25002000-2500 UnconsciousnessUnconsciousness 30 Min.30 Min.

Temperature ExtremesTemperature Extremes

• Extremely hot or cold temperatures.Extremely hot or cold temperatures.• Steam cleaning of confined spaces.Steam cleaning of confined spaces.• Humidity factors.Humidity factors.• Extremely cold liquids.Extremely cold liquids.• Work processes inside the confined space Work processes inside the confined space

can increase temperature extremes.can increase temperature extremes.• Personal protective equipment.Personal protective equipment.

Engulfment HazardsEngulfment Hazards

• Loose, granular materials stored in bins and Loose, granular materials stored in bins and hoppers - grain, sand, coal, etc.hoppers - grain, sand, coal, etc.

• Crusting and bridging below a worker.Crusting and bridging below a worker.• Flooding of confined space.Flooding of confined space.• Water or sewage flow.Water or sewage flow.

Other HazardsOther Hazards

• NoiseNoise» Amplified due to acoustics within the space.Amplified due to acoustics within the space.

» Damaged hearing, affect communication.Damaged hearing, affect communication.

• Slick / Wet SurfacesSlick / Wet Surfaces» Slips and falls.Slips and falls.

» Increased chance of electric shock.Increased chance of electric shock.

• Falling ObjectsFalling Objects» Topside openings expose workers inside confined Topside openings expose workers inside confined

space to falling objects.space to falling objects.

Testing The AtmosphereTesting The Atmosphere

• Verify presence of safe work atmosphere.Verify presence of safe work atmosphere.• Test all areas of a confined space.Test all areas of a confined space.

– Top, Middle, BottomTop, Middle, Bottom

• Methane is lighter than air.Methane is lighter than air.• Carbon Monoxide is the same as air.Carbon Monoxide is the same as air.• Hydrogen Sulfide is heavier than air.Hydrogen Sulfide is heavier than air.• Oxygen Deficiency.Oxygen Deficiency.

VentilationVentilation

• First option to correct problems.First option to correct problems.• Must be aware of hazards you are trying to Must be aware of hazards you are trying to

correct in the confined space.correct in the confined space.• Air intake in a safe location to draw fresh Air intake in a safe location to draw fresh

air only.air only.• Continuous ventilation whenever possible.Continuous ventilation whenever possible.• Retest the confined space before entry.Retest the confined space before entry.

IsolationIsolation

• Locking and tagging out electrical sources.Locking and tagging out electrical sources.• Blanking and bleeding pneumatic and Blanking and bleeding pneumatic and

hydraulic lines.hydraulic lines.• Disconnecting mechanical drives and shafts.Disconnecting mechanical drives and shafts.• Securing mechanical parts.Securing mechanical parts.• Blanking sewer and water flow.Blanking sewer and water flow.• Locking and tagging out shutoff valves.Locking and tagging out shutoff valves.

RespiratorsRespirators

• Air-Purifying RespiratorsAir-Purifying Respirators– Filter dangerous substances from the air.Filter dangerous substances from the air.– Must know the type and amount of hazardous Must know the type and amount of hazardous

substance present in the confined space.substance present in the confined space.– NEVER use with oxygen deficiency!NEVER use with oxygen deficiency!

• Air-Supplying RespiratorsAir-Supplying Respirators– Deliver a safe supply of breathing air from a tank or Deliver a safe supply of breathing air from a tank or

an uncontaminated area nearby.an uncontaminated area nearby.– Must be adequately monitored.Must be adequately monitored.

Standby / RescueStandby / Rescue

• Worker assigned to remain outside the Worker assigned to remain outside the confined space and be in constant contact confined space and be in constant contact with the workers inside.with the workers inside.

• Know emergency rescue procedures.Know emergency rescue procedures.• 50% of workers who die in confined spaces 50% of workers who die in confined spaces

are would-be rescuers.are would-be rescuers.• Trained in use of emergency rescue Trained in use of emergency rescue

equipment and PPE.equipment and PPE.

Permit Entry SystemsPermit Entry Systems

• Written permit signed by entry supervisor.Written permit signed by entry supervisor.• Verifies pre-entry precautions have been Verifies pre-entry precautions have been

taken and the space is safe to enter.taken and the space is safe to enter.• Posted at entry to confined space.Posted at entry to confined space.• Specifies apparent hazards and corrective Specifies apparent hazards and corrective

actions taken prior to entry.actions taken prior to entry.• Requires termination of permit when task is Requires termination of permit when task is

completed or when new conditions exist.completed or when new conditions exist.

Entry Permit RequirementsEntry Permit Requirements

• Date, location, and name of confined space.Date, location, and name of confined space.• Purpose of entry and known hazards.Purpose of entry and known hazards.• Duration of entry permit time.Duration of entry permit time.• Authorized entrants, attendants, supervisors.Authorized entrants, attendants, supervisors.• Air testing results - signature of tester.Air testing results - signature of tester.• Protective measures to be taken.Protective measures to be taken.

» Ventilation, Isolation, FlushingVentilation, Isolation, Flushing» Lockout / Tagout, PurgingLockout / Tagout, Purging

Entry Permit RequirementsEntry Permit Requirements

• Name and phone numbers of rescue and Name and phone numbers of rescue and emergency services.emergency services.

• Communication procedures.Communication procedures.• Special equipment and procedures.Special equipment and procedures.

– Personal protective equipment.Personal protective equipment.– Alarm procedures.Alarm procedures.– Rescue equipment.Rescue equipment.– Respirators.Respirators.

Training and EducationTraining and Education

• All workers who must enter confined spacesAll workers who must enter confined spaces• All attendants and rescue team members.All attendants and rescue team members.• Prior to initial work assignment.Prior to initial work assignment.• Retraining:Retraining:

» Job duties change.Job duties change.

» Change in permit-space program.Change in permit-space program.

» New hazards are present.New hazards are present.

» Job performance indicates deficiencies.Job performance indicates deficiencies.