# Presentation: 554192

## Oxygen Deficiency HazardsODHSAF 103Patty Hunt

## ODH - Oxygen Deficiency Hazards

**ODH - Oxygen Deficiency Hazards**

_**POLICY**_

## ODH training objectives

- 1.  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 provides

**THIS 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.**_

## Slide 5

## Visitor requirements

**To bring a visitor into an ODH 0 or 1 area you must:**

- Have your supervisor’s permission
- escort the visitor:  one ODH qualified escort per visitor
- explain 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

## Slide 11

## Slide 12

## Freon

**1 Liter**

**400 times volume**

## Helium

** ****1 Liter**

**1000 times volume**

## Argon

** ****300 ft ****3**
**Compressed Gas Cylinder**

- (See next slide)

## Argon continued

**A nitrogen spill from a CGC**
**fills 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)

## Argoncontinued

- 10 ft.

- 10 ft.

**60 feet**

**A nitrogen spill from a **
**dewar would fill a**
**10’ X 10’ room 60 feet**
**high, covering 6000 ft****3****.**

## Gas shed

## Slide 20

## 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

**Tunnel**

**Endstation**

**Relay Rack**

**Counting House**

**Injector Service Bldg.**

## Slide 27

## 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 Gas

**Nitrogen****	****	****	****   .97****	**

## Slide 39

## Slide 40

## Slide 41

## Slide 42

## Hazard Avoidance

**WHEN ALARM SOUNDS:**
******  ****EVACUATE**
******  ****DO NOT ENTER PLUME**
******  ****NOTIFY CREW CHIEF**

## Slide 44

## Tunnel plume

## Exit stairwell

## Injector Service Building

## Racks

## Penetration

## Penetration plume

## Rack over penetration plume

## N2 spill test

## Spill Conclusions

- Accelerator
- 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 times
- Necessary 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 normal
- Odor added to the CO2 so that such atmospheres can be recognized
- Warning and instruction signs at entrances and within areas
- Prompt 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 areas
- Other steps or safeguards that are necessary to prevent injury or death based on careful study of each particular situation
- It is recommended that SCBAs be provided for rescue purposes.