Purpose
At Jefferson Lab there is the potential for oxygen deficiency hazards (ODHs) due to cryogens, compressed/solidified gases, and/or clean-agent fire suppression systems, and/or any gas with the potential capability to drive oxygen content downward. This ODH Control Program provides procedures for: determining:
- when an ODH Safety Review or ODH risk assessment is required
- ODH classifications and the associated engineering and administrative controls
- training and medical exclusions to facilitate worker and equipment safety
- the appropriate emergency response
Jefferson Lab considers ODH to be a hazard issue and as such requires training in accordance with Table 1 below. This document complies with applicable federal, state, and local requirements outlined in ES&H Manual Chapter 2410 Appendix T1 Hazard Issues List.
Table 1: Required ODH Safety Training by Job Classification
| Training Course |
Qualified ODH Worker (Areas ODH0-1) |
Qualified ODH Worker (Areas ODH2-3) |
Qualified ODH Worker (Areas ODH4) |
ODH
SAF103 |
X |
X |
X |
Self-Contained Breathing Apparatus
SAF109 |
|
|
X |
5-minute Escape Pack Use
SAF210
|
|
X |
X |
ODH-2 & Respirator Medical Certification
MED13* |
|
X |
X |
|
* Per ES&H Manual Chapter 6800 Appendix T1 Medical Monitoring |
Scope
An ODH exists when the concentration of oxygen is less than or equal to 19.5% (by volume) at a typical barometric pressure of 760 mm Hg. Air normally contains about 21% diatomic oxygen (O2) with the remainder consisting mostly of nitrogen. Individuals exposed to reduced-oxygen atmospheres may suffer a variety of harmful effects. Table 2 contains a list of some of these physical effects and the sea-level oxygen concentrations at which they occur. If exposure to reduced oxygen is terminated early enough, effects are generally reversible. If not, permanent central nervous system damage or death results. Disorientation and unconsciousness can hinder escape from the vicinity of an oxygen deficiency.
Table 2: Effect Thresholds for Exposure to Reduced Oxygen
| Volume % Oxygen |
Effect |
| 17 |
Night vision reduced
Increased breathing volume
Accelerated heartbeat |
| 16 |
Dizziness
Reaction time for novel tasks doubled |
| 15 |
Impaired attention
Impaired judgment
Impaired coordination
Intermittent breathing
Rapid fatigue
Loss of muscle control |
| 12 |
Very faulty judgment
Very poor muscular coordination
Loss of consciousness
Permanent brain damage |
| 10 |
Inability to move
Nausea
Vomiting |
| 6 |
Spasmatic breathing
Convulsive movements
Death in 5-8 minutes |
At Jefferson Lab there are five ODH levels. Refer to ES&H Manual Chapter 6540 Appendix T2 ODH Classifications, Engineering and Administrative Control Practices, Training, and Medical Exclusions. The hazard increases as the number increases. Work areas are classified based on the statistical probability of one fatality due to an ODH in a specified number of worker-hours:
Table 3: ODH Classifications
| ODH Class |
# of worker-hours* during which a fatality is expected |
| 0 |
Greater than 10 million |
| 1 |
from 100,000 hours to 10 million |
| 2 |
from 1,000 to 100,000 |
| 3 |
from 10 to 1,000 |
| 4 |
less than 10 |
| *2000 worker-hours equals one year. |
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Appendices:
T3 ODH Emergency Response
Jefferson Lab utilizes both installed and personal oxygen monitors. A detected oxygen concentration of 19.5% or less triggers an alarm.
- Leave the area immediately and notify your supervisor if:
- An oxygen deficiency warning light (blue) flashes, or
- An oxygen deficiency alarm sounds (i.e.: from an installed or personal oxygen monitor.)
See ES&H Manual Chapter 6540 Appendix T3 ODH Emergency Response Procedure for additional information.
T4 ODH Risk Assessment
An ODH Risk Assessment is performed in accordance with ES&H Manual Chapter 6540 T4 Oxygen Deficiency Hazard (ODH) Risk Assessment:
- when the system involved is complex.
- where experience demonstrates an ODH Risk Assessment has been required in similar systems.
- when the potential for an oxygen concentration below <19.5% exists. For situations where an ODH Safety Review results in an oxygen concentration between 18-19.5%, the ODH Safety Reviewer shall determine whether an ODH Risk Assessment is required.
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Responsibilities:
Management authority may be delegated to a task qualified Jefferson Lab employee at the discretion of the responsible manager.
Anyone at Jefferson Lab
- Observe and follow posted ODH restrictions.
- If a potential oxygen deficiency is indicated by warning lights, alarms, signs of exposure symptoms, visible vapor plume or rushing gas sound immediately follow emergency protocols. Refer to ES&H Manual Chapter 6540 T3 ODH Emergency Response Procedure.
- Complete an ODH Safety Review Form prior to introducing an ODH, prior to alteration of a system or area that might produce an ODH, when an ODH area is recognized, or as requested by a cognizant individual.
NOTE: Where experience demonstrates that an ODH Risk Assessment WILL be required due to low oxygen levels or system complexity, an ODH Safety Review Form need not be completed. The ODH Risk Assessment shall be performed by an ODH Analysis Authority (or designee) in accordance with ES&H Manual Chapter 6540 T4 Oxygen Deficiency Hazard (ODH) Risk Assessment.
Qualified ODH Worker
- Maintain appropriate ODH training and medical approval. For entry into:
- ODH 0 or ODH 1:
- ODH 2 and higher:
- When entering an identified ODH area, follow safety procedures according to the ODH Classification signage and training.
Supervisors/Technical Representative(TR)/Sponsor
Division Safety Officers
- Ensure an ODH Safety Review/Risk Assessment has been performed and is current for any ODH area under your purview. IT IS IMPORTANT TO CONSIDER AND MITIGATE AN ODH EARLY IN THE DESIGN/FABRICATION PROCESS.
- Ensure that engineering and administrative controls required per ODH Risk Assessment under their authority are functioning.
- Review ODH Risk Assessment(s) and associated documentation every 3 years if ODH is present or when conditions change.
- DSOs may delegate all or part of the work associated with these tasks but shall not delegate any responsibility.
ODH Analysis Authority
- Conduct and/or review ODH Risk Assessments when required or requested in accordance with ES&H Manual Chapter 6540 T4 Oxygen Deficiency Hazard (ODH) Risk Assessment. IT IS IMPORTANT TO CONSIDER AND MITIGATE AN ODH EARLY IN THE DESIGN/FABRICATION PROCESS.
- Upon request, perform a review of an ODH Risk Assessment and associated documentation every 3 years if ODH is present or when conditions change.
- Qualifications include:
- Demonstrated ability to analyze and mitigate oxygen deficiency hazards within laboratory user systems.
- Maintain appropriate training SAF103 Oxygen Deficiency Hazard
- Technical proficiencies and knowledge of:
- ODH evaluations, calculations, design/implementation of control measures
- common compressed and liquefied gases, mixed gas properties
- ODH propagation calculations
- Pressurized gas mechanical systems with their associated failure modes analysis
- One of the following:
- Completion of an engineering or physics degree, requiring four or more years of full time study, plus a minimum of five years of experience relating to the technical requirements listed above.
- Professional Engineering registration, recognized by the local jurisdiction, plus experience in systems relating to ODH classification, mitigation, evaluation, and their properties.
- NOTE: Responsibilities of the ODH Analysis Authority shall terminate upon completion and approval of an ODH risk assessment.
ODH Safety Reviewer
- Review and, if acceptable, approve ODH Safety Review document(s) and ODH Risk Assessments.
- Submit a request for a Facility Design Review or ODH Risk Assessment as appropriate.
- Distribute/File final approved ODH Safety Review Forms and Risk Assessments to affected area, Document Owner and ES&H Document Control
- Verify that ODH equipment safeguards, inventory requirements, posting, and labeling are in-place prior to introduction of the ODH.
- Coordinate with DSOs to ensure ODH Risk Assessments are reviewed every 3 years or when conditions change.
- Qualifications include:
- Certified Industrial Hygienist
- Approved by the ES&H Division Head
Industrial Hygiene
- Maintain and provide training for Personal Oxygen Monitors, Escape Packs, and Self-Contained Breathing Apparatus (SCBA).
Engineering Division
- Safety Systems Group and Cryogenic Operations: Install, maintain and calibrate area oxygen monitoring systems associated with accelerator enclosures (e.g. CEBAF, LERF, UITF) under their purview.
- Engineering Division Manager or the Cryogenic Department Head: Approve ODH Risk Assessments.
Physics and Accelerator Divisions
- Install, maintain and calibrate area oxygen monitoring systems under their purview.
Facilities Management and Logistics
- Provide room measurements upon request.
- Provide ventilation capacities upon request.
- Provide and maintain building ventilation systems.
- Install, maintain and calibrate area oxygen monitoring systems under their purview.
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