2 Table of Contents Module 1: Pertinent legislation Module 2: Definitions & TerminologyModule 3: Examples of confined space injuries &/or fatalitiesModule 4: Overview of confined space hazards; hazard identification & assessment processModule 5: Overview of control methodsModule 6: Methods of analyzing, eliminating, & controlling confined space hazardsModule 7: Personal protective equipment / Life Saving EquipmentModule 8: Emergency planning
3 Table of Contents (cont.) Module 9: Legislated documentation requirementsModule 10: Oxygen deficiency & enrichmentModule 11: Flammable gases / hot Work RequirementsModule 12: Toxic atmospheres that are Immediately Dangerous to Life or Health.Module 13: Occupational Exposure LimitsModule 14: Accident Incident ReportingModule 15: Hands on:PPE/rescue equipmentSample permits/ Hazard AssessmentGas monitors
4 Why Train? Often fatal consequences - catastrophic Often multiple injuriesFrequency of incidents is too highWould be rescuers become victimsIceberg principle - lots of incidentsGeneral lack of awareness & training“never happen to me” mentalityGoal of training:Knowledge and skills needed to recognize variety of CS hazardsUnderstand importance of CS entry programHopefully will result in effective implementation of CS entry programAim for Excellence NOT Stupidity!
5 TrainingALL workers who work within confined spaces must receive specific training. Examples of additional training in addition to confined space training:Gas TestingFall Protection training for vertical entryFirst aid/rescue planningALL workers with related duties, such as rescue workers, supervisors, attendants and “fire watch" personnel must also receive training specific to confined spaces.Training records must be kept. Refresher training to be considered.Competence in first aid, the use of appropriate emergency response equipment and appropriate confined spaceprocedures must be developed for workers responding to a confined space emergency. These procedures & plan must be reviewed during the pre-entry safety talk and noted on the permit &/or hazard assessment
6 What are Confined Spaces in Schools? 4 questions need to be asked…an enclosed or partially enclosed space?is it designed or intended for human occupancy?Does it have restricted means of access & egress?Can it become hazardous to a person entering it as a result of:(i) its design, construction, location or atmosphere, or(ii) the materials or substances in it, or(iii) any other conditions relating to it.Needs to meet all of these criteria
12 and/or the lack of oxygen. Apply the 4 CriteriaIs this a confined space ?Trenches & excavations can be confined spaces, if there is a likelihood of hazardous gases, engulfmentand/or the lack of oxygen.
16 LegislationSeptember, 2009 Section 511. Confined Space Entry (1) An employer shall assess the work area to determine whether it contains confined spaces. (2) "confined space" means an enclosed or partially enclosed space that (a) is not designed or intended for human occupancy except for the purpose of performing work; (b) has restricted means of access and egress; and (c )may become hazardous to a person entering it as a result of (i ) its design, construction, location or atmosphere, (ii) the materials or substances in it, or (iii) any other conditions relating to it. (3) A worker shall not work in a confined space after January 1, 2013 unless he or she has completed a confined space entry program prescribed by the commission. (4) An employer shall inform a worker who may have to work in a Confined space of a hazard by posting signs or other equally effective means of advising of the existence of and dangers posed by confined spaces.Limited access & egress can interfere with first aid, evacuation, and rescue
17 Legislation Legislation (cont.) Section 512. Corrective precautions (1) Upon first entering a confined space, a worker shall assume the space is hazardous until the contrary is demonstrated. (2) An employer shall ensure that a worker does not enter a confined space until (a) an adequate assessment of the hazards related to the confined space has been carried out; (b) a source containing a hazardous substance leading to the confined space is safely and completely blocked off or disconnected; (c) a test required under subsection (11) has been completed; (d) the worker is qualified to safely enter and perform duties within the confined space; (e) a written work permit documenting the tests and safety precautions has been completed (f) a set of written safe work procedures has been developed and a worker has been instructed in these procedures. (3) The assessment referred to in paragraph (2)(a) shall be recorded in writing and shall consider, with respect to each confined space, (a) the hazards that may exist due to the design, construction, location, use or contents of the confined space; and (b) the hazards that may develop while work is done inside the confined space.
18 Legislation (cont.)(4) The record of the assessment may be incorporated into an entry permit.(5) Where 2 or more confined spaces are of similar construction and present the same hazards, their assessments may be recorded in a single document, but each confined space shall be clearly identified in the assessment.(6) The employer shall appoint a person with adequate knowledge, training and experience to carry out the assessment and shall maintain a record containing details of the person’s knowledge, training and experience.(7) The assessment shall contain the name of the personwho carries out the assessment.(8) The person shall sign and date the assessment andprovide it to the employer.
19 Legislation (cont.)(10)The employer shall ensure that the assessment is reviewed as often as necessary to ensure that the assessment referred to in paragraph (2)(a) remains current. (11)Appropriate tests for harmful vapours, gasses, fumes, mists, dusts or explosive substances and oxygen deficiency shall be made and recorded (a) before entry into the confined space; (b) after an interruption in the work procedures; and (c) at appropriate intervals. (12)Where a test made under subsection (11) indicates an unsafe condition, the confined space shall be ventilated or cleaned or both and periodically retested to ensure that: (a) the oxygen content is between 20% and 22%; (b) the concentration of flammable substances is maintained below 10% of the lower explosive limit (LEL ) of that substance or substances; and (c) a worker's exposure to harmful substances is maintained at acceptable levels in accordance the TLVs established by ACGIH.
20 Legislation Legislation (cont.) (13) Where gas tests indicate harmful or explosive substances and it is not feasible to provide a safe respirable atmosphere, an employer shall ensure that :(a) entrants wear respiratory and personal protective equipment appropriate to the hazards; and(b) where a flammable or explosive gas or liquid is present all sources of ignition are controlled or eliminated.(14) Where control measures cannot be implemented, a worker shall leave the confined space.(15) Gas tests made shall be performed by a person who has beenadequately trained in the proper use of testing equipment.(16) Equipment used in testing and monitoring shall becalibrated and monitored according to the manufacturer'sinstructions.(17) The completed permit shall be available at the time ofentry to all authorized personnel by posting it at the entryportal or by another effective means.
21 Legislation Legislation (cont.) Section 513. Work procedures (1) If an entrant may be exposed to a harmful atmosphere or may become entrapped by material(a) wears appropriate retrieval equipment for rescue; and(b) has a life-line attached to the retrieval equipment which is tended at all times by a person, stationed outside the entrance able to effect rescue.(2) the use of a lifeline is not required where an obstruction orother condition makes its use impractical or unsafe but, inthat case, an employer shall implement procedures to ensurethe safety of the worker.
22 Legislation (cont.) (3) Entrants require attendants (b) stationed outside and neari) the entrance to the confined space, or if there is more than 1 entranceii) near the one that best allows the attendant to perform their duties;(c) is in continuous communication with the worker as per safe work procedure; and(d) is provided with a device for summoning an adequate rescue response.(4) An attendant shall not enter a confined space and shall,in accordance with the required safe work procedure,(a) monitor the safety of the worker;(b) provide assistance to entrants and rescuers; and(c) summon an adequate rescue response where required.
23 Legislation (cont.) Section 514. Entry into confined space A confined space shall be entered only where(a) opening is sufficient to allow safe passage of a person wearing PPE/safety equipment;(b) mechanical equipment in the confined space is(i) disconnected from its power source, and(ii) locked out and tagged;(c) pipes & other supply lines with hazardous contents are blanked off;(d) measures, where appropriate, to continuouslyventilate space;(e) liquid / free-flowing solid capable of drowning /entrapping have been removed;(f) adequate explosion-proof illumination is providedwhere appropriate; and(g) adequate barriers are erected to prohibitunauthorized entry.
24 OHS-ACT Right to Refuse to Work 45. (1) A worker may refuse to do work that the worker has reasonable grounds to believe is dangerous to his or her health or safety, or the health and safety of another person at the workplace (a) until remedial action has been taken by the employer to the worker's satisfaction; (b) until the committee or worker health and safety representative has investigated the matter and advised the worker to return to work; or (c) until an officer has investigated the matter and has advised the worker to return to work.Steps in process:a. Worker reports the problem to their supervisor stating they are refusing unsafe workb. Supervisor investigates the problem and makes a decisionc. If worker disagrees with supervisor, they proceed to notifying the OHS Committeed. Committee makes decisione. If worker disagrees, then reports refusal to OHS Officer who makes final decisionNot required to be in writing.
25 Owner Requirements Outside Contractors program should meet regulationsprogram needs to be reviewedInform them of your hazard assessmentEnsure they use sop’s/permitsEmergency response planningPeriodically auditincident reporting system – “incidents don’t become accidents”
26 Common TermsCompetent - in relation to a person, means adequately qualified, suitably trained and with sufficient experience to safely perform work without supervision or with only a minimal degree of supervision;Explosive atmosphere - means an atmosphere that(a) contains a substance in a mixture with air, under atmospheric conditions and at a concentration between the substance's lower explosive limit and upper explosive limit,Hazard - means a situation, condition or thing that may be dangerous to the safety or health of workers;Methane in AirToo richUEL15 %LEL5 %Too lean26
27 Common Terms (cont.)Risk – likelihood hazard becomes incident; based on severity, frequency, duration, etcHot work - means work in which a flame is used or sparks or other sources of ignition may be produced, includingcutting, welding, burning, air gouging, riveting, drilling, grinding, and chipping,using electrical equipment not classified for use in a hazardous location, andintroducing a combustion engine to a work process;27
28 Flammability Terms Flash point: Minimum T of which a liquid fuel is heated to give off sufficient vapor to form an ignitable mixture with air (i.e burns)Ignition T:Minimum T req’d for substance to be heated to achieve self sustaining combustion independent of ignition sourceFP is used as a criteria for differentiating flammable liquids, from combustible liquids from non-combustible liquidsCombustible liquids have FP above 37.8 C (less than that is flammable)Also must consider residues that when heated pose significant fire risk that when cold do not register on LEL meterMSDSs give fire and explosion data28
29 Fire Triangle-Tetrahedron Ignition sourceLower flammable limit/flammable rangeFlash Point/Vapor PressureVapor densitySpaces may become flammable as a result of :Product vapors & residuesFuel vapors & residuesCoatings and preservativesLeaking acetylene, propane or gas lines29
30 Lower Limit (LEL)Methane in AirLowest conc. of flammable gas/vapor, expressed in % volume in air, that will burn or explode in presence of ignition source.Below this level, atmosphere is too lean to burn.LEL is lowest part of the flammable range; upper limit is the UELToo richUEL15 %LEL5 %Too lean30
31 Flammable Liquids Flammable vapors exist above volatile liquids such vapors are heavier than air and settle in low spots; travel large distances & igniteGas testing not enough; remove all liquids, residues, sludgeMSDS: look at flash point, vapor pressure, LEL, boiling point, vapor density
32 Section 515 – Explosive Atmospheres Worker not to stay in Confined Space if:> 25%LEL for inspection only; no source of ignition;> 10%LEL - cold work;> 5% LEL &/or > 23% O2 during hot work;
33 Vapor Density Air = 1 Light gases hydrogen Ammonia, methane Air, carbon monoxide, nitrogenpropaneargon, carbon dioxideHydrogen, methane, acetylene, & ammonia are lighter than airChlorine, carbon dioxide, butane, gasoline are heavier than air , hydrogen sulfide 20 % heavier than airChlorine, benzene, gasolineHeavy gases33
34 Hazard Identification System to ID all hazards existing in absence of controls; control minimizes riskEvery CS hazardous unless determined otherwise by risk assessmentTake into account:Routine & non-routine activities in & out of spaceFacilities & activities of adjacent spaces/workplaceContents and supply lines into/out of the space
35 Hazard Identification Process Engulfment or entrapment by liquids/materialsPotential for fire or explosion, oxygen deficiencyBiological hazards – crawl spacesPhysical hazards- Temperature - Noise - Humidity - Lighting - ErgonomicsFlammable residues - fire resistant coveralls ineffectiveToxic hazards – lead, asbestos, VOC’s, etc
36 Risk Assessment Eliminate hazard Best OptionEliminate hazardSubstitute hazardous materials, processes, equipmentEngineering controlsAdministrative controlsPPE-selection, use & maintenanceRemove flammable or toxic residues, isolate gas lineCold work versus hot workAdequate ventilation setup; lock-outs/de-energizing / ensuring safe access & egressD. signage, training, sop’sPPE-least effective but often necessaryLeast Preferredoption
37 Classification of Confined Spaces Most confined spaces are designed to hold substances such as liquids, gases, and loose materials, or to house equipment.Though they come in many sizes and shapes, most can be classified in one of two ways:1. Spaces that are open-topped and have depth• pits • well • bins2. Spaces with narrow openings• pipes • utility vaults• Attics • HVAC
38 Confined Space Entry Definitions Entrant is the person who enters a confined space.Attendant stays outside the confined space, monitors the space, responsible for assisting the entrant, summons assistance in emergency.Safety representative (or entry supervisor) is the competent person who assesses the hazards, lists necessary equipment and control measures, controls Confined Space Entry Permit process.
39 Attendant Remain alert outside space summon help if needed but do not enterConsider activities outside spaceMaintain 2 way communicationKnow hazards posed & work requirementsassess conditions/changes that may impact entrantsEnsure controls measures working properlyInitiate emergency procedures as per sopPerform non-entry emergency rescue if safe to do so
40 Entrant Remain alert at all times Aware of all potential hazards Aware of symptoms & warning signs of exposureReport concerns to attendantExit immediately if conditions warrant, alarms sound, or if directedDon’t be afraid to ask for safety infoYou have a right to be made aware of all potential hazards
41 Hazard Assessment Form Assessment must be carried out by a qualified person, and form completedMust identify existing and potential hazardsMust contain name of person performing assessmentMust be signed and datedMust be copied to Occupational Health and Safety CommitteeMust be recorded and maintained in filing systemHas been separated into sections for ease of use
42 Assessment Form Sections Access into the confined spaceInternal configuration and features of the confined spaceElectrical hazardsMechanical hazardsEngulfment HazardsExternal HazardsCommunicationsVentilationAdverse temperaturesNoise / VibrationChemical HazardsOther Considerations
43 1. Access into Confined Space Entrance/Exit Accessibility and ConfigurationEntrance/exit easily accessible?Type: Round, Oval, Square, Other?Vertical Entry/ExitStairs, Fixed ladder, Portable ladder, Other?Condition?Tripod to be used?Horizontal Entry/ExitElevated entry/exit?Work platform provided?
44 2. Internal Configuration and Features Use & Shape of a space can create hazardous conditions:Low Ceilings?Walk inErectStoopedHead Hazards?Footing inside space?Narrow areas entrapping entrant/rescuerSloping surfaceUneven surfaces & bends*Use retrieval and fall protection when possiblecreate challenges for attendant to communicateNeed to protect openings with barricades
45 2. Internal Configuration (Cont.) Other Internal features of space?Wet or slippery surfacesPoor lightingSharp objectsMoldPipelines going through the space?Use of ladders & scaffolding?*Use retrieval and fall protection when possibleNeed to protect openings with barricades
46 3. Electrical Hazards Possible contact with energized conductors? Controls: Lockout procedures, GFCI’s, grounding & bonding, double insulated toolsHazardous sources:- Broken/energized lighting & power- Damaged cords- Welding equipment not grounded/bondedWet surfaces confound problemsExplosion/vapor proof lighting mayneed to be assessedSources of ignition: grinding, welding & burning, static electricty, powder actuated toolsBondingConnect 2 or more electrically conductive objects together by means of a connecting bridge (metal wires)GroundingConnect 1 or more metallic objects to the ground and is a specific form of bonding.CSA C22.1 Canadian Electrical Code Part 1 Safety Standardfor Electrical Installations, Clause 18 “Hazardous Locations”
48 5. Engulfment Hazards Chemical? Sludge/sewage? Other hazardous liquid (water)?Lock out and/or Isolate:physically prevent and/or disconnect pipes & energy sources by applying controls:Such as:Locks,Tags,Blanks & blindsDouble block & bleed
49 6. External Hazards Traffic hazard? Parking lot (loading area/parking spaces in vicinity)?Precipitation?Overhead electrical wiresSpill or possibility of objects falling into opening?
50 7. VentilationSpace has configuration that will hamper ventilation/purging?Convoluted space?Large volume?Other?
51 8. Communications Entrants can be visually observed by attendant? Voice only adequate?Visual hang signal adequate?Internal telephone available?Cell phone required?Radio required?Intercom?Rope Signal?
54 11. Chemical Hazards Pipes/lines? Accumulation of: Flammable/combustible/oxygen enrichedOxygen deficient atmospheresToxic atmosphereOxygen deficiency can be caused by:Consumption: oxygen is used up (respiration, fire, bacterial action)Displacement: heavier materials push out normal air (argon, CO2, freon) .Reaction: air reacts with other materials to make other compounds (oxidation-rust).The air that leaves a person's lungs during exhalation contains 14% oxygen and 4.4% carbon dioxide.Combustion uses up O2 faster than respiration
55 Symptoms of Oxygen Deficiency 11. Chemical Hazards (cont.)Symptoms of Oxygen DeficiencyPercent of Oxygen in AirSymptoms in workers20.9%Normal Air, NO Symptoms19.5%Minimum allowable level18%Early symptoms, Decreased ability to work16%Increased heart and lung rate14%Impaired judgement and coordination , FatigueLoss of peripheral vision12%Nausea and Vomiting, Extreme FatigueLess than 10%Nausea and Vomiting, unconsciousness, convulsions, death
56 Symptoms of Oxygen Deficiency 11. Chemical Hazards (cont.)Symptoms of Oxygen DeficiencyDoes lack of oxygen cause shortness of breath?Are there adequate warning signs of oxygen deficiency?
57 11. Chemical Hazards (cont.) Oxygen EnrichedLevels above 21%.flammables & combustibles burn faster & harderDon’t use pure oxygen to ventilate.Don’t store oxygen tanks/hoses in a confined spaceWear fire resistant clothing
58 11. Chemical Hazards (cont.) Flammable liquidsFlammable vapors - above liquid surface often heavier than air (lower tank region)Vapors can reach great distances to ignition sourcesFire prevention:Remove all hydrocarbons, vapors & flammable gases from tanksEliminate ignition sourcesProperly ventilate space to dilute vapors
59 11. Chemical Hazards (cont.) Chemical ToxicityChemicals bought into spaceFugitive emissions (welding, solvents, degreasers)Waxy surfaces (hydrocarbons)No magic meter to test all chemicalsNeed to refer to MSDS’s & hazard assessmentConsider skin & inhalation hazards
60 Immediately Dangerous to Life and Health (IDLH) 11. Chemical Hazards (cont.)Immediately Dangerous to Life and Health (IDLH)Airborne levels of hazardous substances that may:Impair the worker's ability to safely leave the dangerous situationLead to irreversible or delayed health effects, serious injury, or death in a short periodUsed for purpose of respirator selection
61 ACGIH TLVs - Time Weighted Average 11. Chemical Hazards (cont.)ACGIH TLVs - Time Weighted AverageTWA = Concentration at which workers can be repeatedly exposed day after day without adverse health effectsCan exceed TWA from time to time as long as average exposure not exceededSome chemicals require us to be concerned even for short term exposuresSTEL (Short Term Exposure Limit)Ceiling limit
62 11. Chemical Hazards (cont.) Carbon MonoxideFormed by incomplete combustionColorless, odorless gas, non irritatingSlightly lighter than airCauses suffocation without warningGo unconscious at high concentrationsLEL = 12.5%, TWA=25 ppmNIOSH IDLH = 1200 ppmSampling: gas meter or colorimetric tubesTypical respirator not adequateNo odor or warning properties at safe levels, first symptoms are headaches, dizziness and nausea (by this time may be too late)No approved air purifying respirator cartridge
63 11. Chemical Hazards (cont.) Hydrogen SulfideSewer gas –rotten egg smell-organic breakdownColorless, flammable gas at high concentrationsTLV=10 ppm; STEL=15 ppm; NIOSH IDLH=100 ppmNatural component of crude oil (heavy/sour crude)Paralyzes sense of smell (can’t rely on smell)heavier than airMutligas meter or colorimetric tubes
64 Chlorine - Chlorinators 11. Chemical Hazards (cont.)Chlorine - Chlorinators3 forms: liquid (4 %); solid (12 %) & gas 100 %Pungent irritating corrosive gasUpper respiratory & eye irritationHeavy gas (Vapor density > air)Ventilate at low levelsTLV-TWA = 0.5 ppmTWA-STEL = 1 ppm (15 minute)Colorimetric tubes
65 11. Chemical Hazards (cont.) Air MonitoringAssesser must be competentCalibrate monitorsRemote sampling first, then enterReassess to ensure conditions stay safebefore entry; after break in work; & at appropriate intervalsIf tests indicate unsafe condition; ventilation &/or clean & retest so that:O2 is between 20 & 22 %< 10 % LFLACGIH TLVs not exceededPermit to be posted at portal entry (with gas testing results)Consider worst case scenario for testing: shut off ventilation before testing & retest with ventilation on
66 11. Chemical Hazards (cont.) How to test?Need to test remotely first at least 3 different levels to see if results varyvapor density is importantHint: test exhaust airsludge can give off volatiles if heated or disturbedVarious types of air testing equipmentEquipment must be calibrated on a regular basisMust perform bump tests on regular basisAsk for calibration logs and maintenance recordsAsk about bump testsAsk about alarm settingsAsk what they look for first on monitor – Oxygen is most impt!Then LEL and finally toxics
67 11. Chemical Hazards (cont.) Air Monitoring Cont’dPass or fail scenarioNot looking for 100 % accurate readingsUse portable fairly accurate instrumentsgas meter – oxygen, LEL, CO, H2S,colorimetric tubes – , Cl2, CO2,, NO2, etcPID – TVOC’s (hydrocarbons)Is it safe or unsafe for entry!
68 Calibration vs. Bump Test 11. Chemical Hazards (cont.)Calibration vs. Bump TestCalibration - gases of known concentration verify instrument is measuring properly (quantitative test)Bump test – a short burst of gas to ensure that sensors and alarms are working (qualitative test)
69 Detector Tubes Numerous Toxic Gas/Vapors 11. Chemical Hazards (cont.)Detector Tubes Numerous Toxic Gas/VaporsChemical reactions colored reagentLength of colored stain = concentrationPump (draws 100 ml)Need to follow instructionsSimple procedure but limitations+ interferencesAccuracy: + or – 30 %Draeger, Gastec, KitigawaNeed to know contaminant of concernGrab samples onlyCO = silica sand with colorless solution of iodine pentoxide in tube; produces brown iodine
70 Photo-ionization Detector 11. Chemical Hazards (cont.)Photo-ionization DetectorReal time measurements of TVOC’sUniversal detector (not selective)Very sensitive (volatile toxics & flammables)
71 12. Other ConsiderationsStructural integrity?Rodents/animals?
74 Confined Space Hazards Hazards found in confined spaces can be placed in the following groups: a.) Oxygen deficient atmospheres can be caused by rusting of a steel vessel, any form of burning (including welding & brazing), absorption by grain or soils, and consumption by bacteria. b.) Asphyxiant gas physiologically inert gases can dilute or displace atmospheric oxygen below the level required for normal human functioning examples of asphyxiant gases are carbon dioxide, ethane, helium, hydrogen, methane, and nitrogen. c.) Toxic atmospheres - containing gases, vapours, dusts or fumes that have poisonous effects on the body. Cleaning, painting or welding may produce dangerous vapours or fumes. Gases such as hydrogen sulphide may leak into or be released from sludge present in the confined space. Carbon monoxide may be generated in the space by an internal combustion engine. Methane may be created through the fermentation of plant material in the space.
75 Confined Space Hazards d.) Flammable or explosive atmospheres - containing flammable gases, vapours or dusts that could be ignited by a spark or open flame. The risk of explosion increases if an oxygen enriched atmosphere is present.e.) Engulfment - workers can be trapped or buried by dry bulk materials such as grain, sand, flour, fertilizer and sawdust.f.) Operation of moving parts being trapped or crushed by augers, mixers, agitators, or conveyor belts.g.) Uncontrolled introduction - of steam, water or gash.) Other hazards - these could result from the work being done Examples are noise, extremes of temperature, radiation, manual handling and falls.
76 “HOT” WorkAny situation involving the risk of fire or explosion is considered to be a “hot work” hazard situation, if the work being done could generate a spark. Common hot work hazards would include, but are not limited to:cutting - weldingburning - air gougingriveting - drillinggrinding - chippingthe use of non-classified electrical equipmentplacing a combustion engine in the confined spaceIf a hot work hazard situation exists, a special hot work hazard safe work permit must be issued.
77 Confined Space Complications NoiseConfined space can amplify sounds Noiseinterferes with essentialproduced by tools and equipment. communication between entrants and attendants.Falling objectsObjects fall into the space because topside openings are unguarded or improperly guarded.Extreme temperaturesThe space's location and equipment make it hot or coldEnvironments put workers at risk. equipment it contains make it ideal for heat stress, doing strenuous work or wearing protective clothing make tasks more difficult to accomplishSlippery SurfacesLeaks, spills and condensation makewalking surfaces slipperyWet surfaces are usually slippery. They increase the risk of falls.
78 Hazard Control Methods Methods used to control hazards found in confined spaces fall into three categories:1.) Engineering controls - ex. ventilation systems2.) Administrative controls - ex. entry permit system3.) Personal protective equipment ex. supplied air breathing apparatusEngineering controls are designed to eliminate the hazardadministrative controls and personal protective equipment try to minimize the hazard.
79 Hierarchy of Controls Eliminate hazard Substitute with other materials Use engineering control measuresUse administrative controlsPPE
80 Eliminating and Controlling Hazards Once an existing or potential hazard is identified, an employer is required to eliminate the hazard or if elimination is not reasonably practicable, control the hazard.If reasonably practicable, an employer must eliminate or control a hazard through the use of engineering controls.If this can not be done, the employer must use administrative controls that control the hazard to a level as low as reasonably achievable.If engineering and administrative controls will not control the hazard, then an employer must ensure the appropriate personal protective equipment is used by workers affected by the hazard.
81 Atmospheric HazardsThe following are examples of practices used to eliminate and control atmospheric confined space hazards.Cleaning the space to remove contaminants. For example: use a vacuum and hose to remove petrochemical sludge,Replacing an unsafe atmosphere with clean respirable air by purging and ventilatingReplacing the unsafe atmosphere before entry usually involves mechanical ventilation to blow or suck fresh air in and continuously move it throughout the space.
82 Atmospheric Hazards (cont.) Preventing fires and explosions. Fire prevention requires control of the three elements needed for a fire or explosionInerting the confined space. Inerting is used to eliminate hazards such as chemical reactions, flammable vapours, and the possibility of explosions.Using continuous ventilation to keep the atmosphere safe.
83 Physical Hazards Loose and unstable material. Shoring of unstable trench or evacuation wallsRemoval of unstable material from confined space before entry.Requirement for lifeline and harness and provision for immediate rescue of a worker in distress.Moving parts of machinery.Locking out. The use of a Lock or locks to render machinery or equipment inoperable or to isolate an energy source.
84 Electrical Hazards Substitute pneumatic tools for electrical ones. Properly grounded tools.Double-insulated tools.Use of ground fault circuit interrupter.
85 Basic Personal Protective Equipment The type of PPE to be worn will depend on the job to be done and the hazards that have been identified. PPE considered basic for almost any job are:Employees are responsible to ensure their PPE is clean, properly maintained, in good serviceable condition, CSA approved, and suitable for the type of work to be performed.approved safety footweargloveshard hatsafety glassesflame retardant coveralls
86 Personal Protective Equipment Determined by hazard /risk assessment- based on hazardsNoted on entry permitProtective clothing: chemical (corrosive/toxic) & flame resistant (residues)Need to consider hazardous materials (mold, asbestos, lead)Hydrocarbon stained coveralls can affect fire resistant clothingGarments: chemical resistance, appearance, comfortAmong the more widely used fibers for protective clothing are NOMEX, INDURA and FLAMEX.
87 Air Purifying Respirators Mechanical filters – NRP – 95,99,100Chemical cartridges – OV, AGCombination of OV/AG/HEPANegative (+) pressure field checkQualitative fit testCSA program & training – CSA Z94.4“Selection Care & Use”Don’t protect against oxygen deficiency
88 Respiratory Protective Equipment Selection of respiratory protective equipment depends on the type of work and the hazards to be encountered.There are three main types of respiratory protection devices:1. Dust Masks - these masks may be disposable or reusable and are designed to filter out certain particles, mists and some fumes.2. Canister or Cartridge - cartridge respirators can only protect you against the specific hazard(s) and specific concentration levels as identified on the canister/cartridge. The canister or cartridge respirator has limited use in confined space entry work.3. Supplied Air - these devices are designed to supply fresh air from an independent and safe source.
89 Respirator Programwritten program with worksite-specific procedures when respirators are necessaryprovide necessary training on selection, use, care & limitations and medical evaluations as per CSA Z94.4Program elements:1. Selection Medical evaluation3. Fit testing Use5. Maintenance and care 6. Breathing air quality and use7. Training Program evaluation89
90 Supplied Air Apparatus Air-Supplying RespiratorsDeliver a safe supply of breathing air from a tank or an uncontaminated area nearby.Supplied Air Breathing Apparatus (SABA)The SABA has a positive pressure face mask connected by an airline to a cylinder of compressed breathing air not carried by the worker. For safety purposes, the SABA comes equipped with an egress bottle of air which is carried by the worker. This bottle contains a maximum of five minutes of air supply. In an emergency the worker disconnects the air line and turns on the egress bottle. SABA respirators are commonly used when the work to be performed will take several hours.
91 Supplied Air Apparatus Self Contained Breathing Apparatus (SCBA)The SCBA has a positive pressure face mask connected to a compressed air cylinder which is carried by the worker. This type of equipment provides a limited air supply. Due to this limitation, SCBA respirators are best suited to perform short term and emergency tasks.The amount of air supply possible will be affected negatively by many factors including:• condition of the equipment• was it filled properly• temperature bottle was filled at versus temperatureit will be used in• physical condition of the person using the SCBA• physical size of the person using the SCBA• workers emotional state and experience level• exertion level required of worker
92 Emergency ResponseThe emergency response plan must include the emergency procedures to follow in the event of an emergency, including procedures to evacuate the confined space immediately if:an alarm is activatedthe concentration of oxygen inside the confined space moves outside of the acceptable rangethere is a significant change in the amountof hazardous substances inside theconfined space.Plan must be in writing & explainedto entrants
93 The Emergency Response Plan Emergency response plans must include the following: • the identification of potential emergencies, • procedures for dealing with the identified emergencies, • the identification of, location of and operational procedures for emergency equipment, • the emergency response training requirements, • the location and use of emergency facilities, • the fire protection requirements, • the alarm and emergency communication requirements, • the first aid services required, • procedures for rescue and evacuation, and • the designated rescue and evacuation workers.
94 The Emergency Response Plan (cont.) Additional items that you may want to include in a rescue plan are: • dimensions of the space, location of entry and exit points, and obstacles to removing an injured worker, • possible hazards that may arise during rescue, the appropriate evaluation of these hazards, and control methods recommended by the qualified person, and • rescue methods for a worker who is unconscious (on or off of a lifeline), or distressed.Drills must be carried out periodically
95 Types of Rescue Self rescue: entrant capable of exiting unassisted External rescue: need outside assistance without additional entry; opening & path unobstructed to allow external Retrieval system (already set up).Entry rescue: entrant needs assistance to escape; but opening &/or path obstructed, or entrant needs to be assessed/helped before moving themIDLH entry rescue: unknown atmosphere or immediately dangerous to life & health condition. Time is critical. Principle: “life over limb” is allowed.Assumes early warning of developing hazardImportant for workers to be wearing harness & tethered to extraction line for easy extractionCS may have obstacles, or more than 3 metres horizontally to move injured worker95
96 Emergency Response Group Internal or externalNot become victims themselves-assess-sop’sReady to respond when notified minutes for IDLHTrained and properly equippedLocate the entrant(s), stabilize them, package & extract themEnsure proper first aid equipment on sitePrior to entry be given opportunity to prepare extraction planDetermine # persons req’d to extract personnelEnsure req’d actions taken before sending in rescue personnel (ie. Proper equipment, capabilitiesMaintain appropriate communication throughoutExternal rescuers must be made aware in advance of site, spaces, hazards, through appropriate drills and be briefed of same prior to rescueNeed to be trained in: physical distress systems recognition training, personal protective devices, communication systems, supplied air breathing apparatus, spinal board packaging, severe bleeding management, hazard ID, evaluation, & control, knowledge of managing an emergency response incident96
99 Tending WorkerFor every confined space entry, an employer must designate a competent worker to be in communication with a worker in the confined space. The “tending person” does not have to be immediately outside the confined space unless the following point comes into play. * the oxygen content of the atmosphere inside the confined space is Less than 19.5% or greater than 23.0% * a hazard is identified by the hazard assessment and the hazard cannot be eliminated or effectively controlled.
100 Tending Worker (cont.)The role of the tending worker is to monitor the safety of the person(s) working inside the confined space and to take action if an emergency arises. This tending worker must:• keep track at all times of the number of workers inside the confined space• be in constant communication with the workers inside the confined space,• have a suitable system for summoning assistance, and• not leave the area until all workers have left the confined space or another tending worker is in place.
101 Safe Work PermitA safe work permit is a document that identifies the work to be done, the hazard(s) involved, and the precautions to be taken. It ensures that all hazards and precautions have been considered before work begins. Safe work permits should always be used when work is performed by an outside agency or employer.What is a safe work permit?A safe work permit is a written record that authorizes specific work, at a specific work location, for a specific time period. Permits are used for controlling and coordinating work to establish and maintain safe working conditions. They ensure that all foreseeable hazards have been considered and that the appropriate precautions are defined and carried out in the correct sequence.Employers are required to provide workers with a safe place of work and to identify known safety hazards. This can be partly achieved through the use of a safe work permit system.
102 Safe Work Permit (cont.) There are two types of safe work permits. 1. Hot Work Permit Hot work permits are used when heat or sparks are generated by work such as welding, burning, cutting, riveting, grinding, drilling, and where work involves the use of pneumatic hammers and chippers, non-explosion proof electrical equipment (lights, tools, and heaters), and internal combustion engines. 2. Cold Work Permit Cold work permits are used in hazardous maintenance work that does not involve "hot work". Cold work permits are issued when there is not reasonable source of ignition, and when all contact with harmful substances has been eliminated or appropriate precautions taken.
103 Entry Permit SystemA confined space entry permit is essentially a document that sets out the work to be done and the precautions to be taken.It can function as a safety checklist to make sure that nothing is overlooked.A worker must not enter a confined space at a worksite without a valid entry permit.The entry permit must, at a minimum:List the name of each worker who enters the confined space and the reason for their entryProvide the location of the confined space,Specify the time period for which the entry permit is validTake into account the work being done in the confined space, and therefore the safety precautions that must be taken, and take into account the code of practice requirements for entering, being in and Leaving the confined space.The completed, signed permit must be kept readily availableIf an employer performs a hazard assessment of a representative sample of identical confined spaces, then a single entry permit can be used for these and any additional identical confined spaces
104 Confined Space Entry Permit Location and description of confined space:Reason for entry:Permit issued to:Supervisor’s Name:Attendant’s name:Permit issuer’s name:% oxygen: % lower explosive limit: ppm CO: H2S:RequirementsEmergency Rescuer yes noContinuous Gas Monitor yes noBarrier for ground openings yes noWarning Signs yes no
105 Confined Space Entry Log The entry log is a document kept by the Safety Watch (Monitor). It is an up to the minute running account of the personnel inside the confined space. Recommended information includes: • the name of each worker • their personal protective equipment • the time the confined space was entered • the time the confined space was exited, and • the total number of workers in the confined space.
106 Oxygen Deficiency Oxygen Deficiency A worker enters an enclosed area and collapses. Another worker rushes in to rescue the first worker. Both workers die. A worker enters a confined space. When he doesn't come out, a co-worker goes after him. A third worker tries to hold his breath and rescue both. All three workers die.Can I tell if the air doesn't have enough oxygen?NO! Air that is low in oxygen has no warning properties. You can't smell, taste, or see any difference. By the time you feel faint or dizzy, you may not have enough energy or alertness to escape
107 Oxygen Deficiency (cont.) • Oxygen is used up when metals rust. • Oxygen is used up during combustion - for example, by propane space heaters, during cutting and welding, and by internal combustion engines, • Oxygen is replaced by other gases used in industrial processes for example, welding gases or gases forced into the space to prevent corrosion. • Oxygen is replaced by gases leaking into an enclosed space through drains or other openings. • Micro-organisms use up oxygen - for example, in sewer lines and fermentation vessels. The only way to know what the oxygen level is in the atmosphere is to test for oxygen levels with a properly calibrated oxygen tester.
108 Inert AtmospheresInerting is the process of intentionally replacing the atmosphere inside a confined space with an inert gas such as nitrogen. Inert means that the gas will not react or cause an explosion or fire.Inerting creates an oxygen deficient atmosphere because the air (with its oxygen) has been replaced by another gas.Inerting is used to eliminate hazards such as:• chemical reactions• flammable vapours• the possibility of explosions• to prevent oxidation (rusting) of equipment or the walls of the confined space
109 GASESCarbon Monoxide Gas (CO) - CO usually comes from the exhaust of gasoline engines and it is both odourless and colourless. Ringing in the ears, nausea, headaches and sleepiness are common symptoms of carbon monoxide poisoning.Gasoline - Gasoline is in such wide spread use by the general public and industry that gasoline vapours are likely to be found almost anywhere. The average person can smell gasoline at 10 ppm.Other toxic gases commonly associated with confined space entry are:• Ammonia• Chlorine• Carbon dioxide• Benzene• H2S – Hydrogen Sulphide• Vapours of the toxic component in cleaning products being used in the confined space
110 LEL and UELLower Explosive Limit is defined as "the minimum concentration of combustible gas or vapour in air, expressed as a percentage by volume, which will ignite if a source of ignition is present". Below this Level the mixture is too Lean to ignite (there is not enough of the gas or vapour present to form an explosion hazard).In contrast, the Upper Explosive Limit, "the maximum concentration of combustible gas or vapour in air, expressed as a percentage by volume, which will ignite if a source of ignition is present". Above this level the mixture is too rich to ignite (there is too much of the gas or vapour present or too little air to form an explosion hazard) .
111 OEL & STEL Occupational Exposure Limit The maximum airborne concentration of a substance a worker may safely be exposed to for an eight hour period.Short Term Exposure LimitThe maximum allowable exposure of a toxic substance a worker may safely be exposed to over a 15 minute period. Regulations allow only four 15 minute exposures per day with at least one hour between each exposure.
112 Incident Investigation Report all hazardous occurrences – spvsrComplete Hazardous Occurrence reportNot to find blame but to learn from themLessons learned new sop’sMost fatalities investigated reveallong term deficiencies/incidentsbefore fatal event !
113 Ventilation Requirements Purpose: prevent 02 deficient, toxic & flammable atmospheresSome sources: 1/3rd the volume of CS per minute for low level contaminantsVentilation: primary means to control toxic airAir testing determines actual ventilation requirementsmechanical ventilation: 2 types –General supply & exhaust & local exhaustNatural ventilation is not reliableMore efficient to push air than to pull airtest CS before and after introducing ventilation
115 Welding In CS not allowed without special Hot Work permit sign off req’d by safety officer & supervisorLocal exhaust at sourceGeneral dilution – minimum 2000 cfm/welderHEPA/P100 respirators as minimumfire resistant clothingSpecial air monitoringrequirements