oxygen deficiency hazards odh saf 103 patty hunt
DESCRIPTION
Oxygen Deficiency Hazards ODH SAF 103 Patty Hunt. ODH - Oxygen Deficiency Hazards. POLICY. Personnel will not enter or occupy areas in which oxygen concentration is less than 19.5%. 1. Health Effects of ODH 2. ODH Hazards that can be Encountered at Jefferson Lab: - PowerPoint PPT PresentationTRANSCRIPT
Oxygen Deficiency Hazards
ODH
SAF 103
Patty Hunt
Personnel will not enter or occupy areas in which oxygen concentration is less
than 19.5%
ODH - Oxygen Deficiency Hazards
POLICY
ODH training objectives1. Health Effects of ODH
2. ODH Hazards that can be Encountered at Jefferson Lab:
Cryogenic and Non Cryogenic Sources
3. Special Hazards from handling Ultracold Liquids
4. Jefferson Lab Controls for Cryogenic ODH:
•Identification and Classification of ODH Areas
•Worker Requirements for Entry into ODH Areas
•Engineering Controls Used to Reduce ODH Hazards
•Emergency Response Procedures
Training providesTHIS TRAINING DOES PROVIDE:
• qualification for entry to ODH 0 and ODH 1 areas
• retraining required every 12 months
ODH 2 AND HIGHER WORK REQUIREMENTS REQUIRE
• medical approval
THIS TRAINING DOES NOT QUALIFY YOU FOR
CONFINED SPACE ENTRY.
Visitor requirements
To bring a visitor into an ODH 0 or 1 area you must:
Have your supervisor’s permissionescort the visitor: one ODH qualified escort per visitorexplain the ODH hazards to the visitor before allowing them to enter the ODH area
TOUR GROUP REQUIREMENTS: OSP/TOSP
OSP
N2 vent
Manure pit
Nitrogen Bubble
Freon
1 Liter
400 times volume
Helium
1 Liter
1000 times volume
300 ft 3
Compressed Gas Cylinder
Argon
(See next slide)
Argon continued
A nitrogen spill from a CGCfills 300 cubic ft. or a room 10 ft. X 10 ft. 3 feet above floor level.
3 feet
10 ft.
10 ft
.
Compressed gas cylinder
Argon 6000 ft 3
Dewar
(See next slide)
Argoncontinued
10 ft.10
ft.
60 feet
A nitrogen spill from a dewar would fill a10’ X 10’ room 60 feethigh, covering 6000 ft3.
Gas shed
Site ODH Areas
Site ODH Areas
Test lab tank
Dewar service bldg
4 Important Properties of Cryogens
• Cryogens can liquify other gases.
• Cryogens can cause frost bite.
• Cryogens have high expansion ratio on vaporization.
explosion hazard
ODH hazard
• Cryogenic gases rise or sink depending on density.
Tunnel Endstation
Relay Rack
Counting House
Injector Service Bldg.
Electronic Relay Racks
Helium
25 Ft
TunnelCryomodule
Service Building
Helium Transfer Line
PPE
Helium Transfer Line
Pressure relief valves
Nitrogen small plume
Nitrogen large plume
Helium lintel
Lintel in tunnel
Exhaust duct
Closed penetration
Properties of GasSpecificDensity
Hydrogen .07Helium .14Neon .70Nitrogen .97
Air 1.00Oxygen 1.11Argon 1.39Carbon Dioxide 1.70Freon 4.35
Hazard Avoidance
WHEN ALARM SOUNDS:
EVACUATE
DO NOT ENTER PLUME
NOTIFY CREW CHIEF
TunnelCryomodule
Service Building
25 ft
Electric Relay Racks
Helium
Tunnel plume
Exit stairwell
Injector Service Building
Racks
Penetration
Penetration plume
Rack over penetration plume
N2 spill test
Spill ConclusionsAccelerator
• Tunnel is safe
• Lintels are working
• Service Buildings are safe
• Working with your head inside a relay rack is a hazard
• Service Building "plumes" are not visible for minor spills,
but are for major spills
End Stations
• Helium can only cause an ODH problem above the crane
Inside Hall A
Crane rail
CO2 Cylinders and Manifolds
CO2 fire extinguishing system discharges killing 2 workers
Switchgear looking west toward exit door Motor Generator Room
External Requirements - NFPA 12 - Carbon Dioxide Extinguishing Systems
• Warning signs at entryways to protected spaces and adjacent areas where the CO2 could migrate.
• All persons that can enter the space shall be warned of the hazards, given the alarm signal, and provided with safe evacuation procedures.
• The pre-discharge warning signal shall provide significant time delay to allow for evacuation under worst case conditions.
• All personnel shall be informed that discharge directly at a person will cause eye injury, ear injury, or even falls due to loss of balance upon impingement.
• To prevent accidental or deliberate discharge, a “lock-out” shall be provided when persons not familiar with the system are present in a protected space.
• Consideration shall be given to the possibility that personnel could be trapped or enter into an atmosphere made hazardous by discharge. Suitable safeguards shall be provided to ensure prompt evacuation, to prevent entry into such atmospheres, and to provide means for prompt rescue of any trapped personnel. Personnel training shall be provided. Pre-discharge alarms shall be provided.
Additional Information in NFPA 12, Appendix A indicates consideration should be given to:
Adequate aisleways and routes of exit kept clear at all timesNecessary additional or emergency lighting and directional signals to support quick safe evacuation.Only outwardly swinging self closing doors at exits with provisions for panic hardware as necessary.Continuous alarms at entrances until the atmosphere has been returned to normalOdor added to the CO2 so that such atmospheres can be recognizedWarning and instruction signs at entrances and within areasPrompt discovery and rescue of persons rendered unconscious in such areas (This can be accomplished by search by trained personnel with appropriate breathing apparatus immediately after discharge stops)Instruction and drills for all personnel within the area including maintenance construction personnel that may work in the area.Means for prompt ventilation of such areasOther steps or safeguards that are necessary to prevent injury or death based on careful study of each particular situationIt is recommended that SCBAs be provided for rescue purposes.