Clearance and Tagging Flashcards
1
Q
State the specific conditions that do not require a clearance to be utilized.
A
- Hazard is not complex.
- isolation points are, at a minimum, within the worker’s line of sight and close enough that the worker can prevent others from operating.
- Work activity is performed by one individual or a two-person team when only one of the two is performing hands-on work.
- Activity performs minor servicing of operational equipment
- Minor servicing is performed on a periodic basis or in the course of the worker’s routine activities.
- All installed personnel safety guards and personnel safety interlocks remain intact and/or are properly used.
- Work does not extend beyond the worker’s shift, unless a proceduralized turnover process exists and the work will be conducted continuously.
- Work is controlled by approved plant procedures or work instruction that identifies the hazard, the protective measures, and includes specific steps for accomplishing the activity.
- Work is a normal part of the worker’s craft or assignment.
- Worker is qualified to service the equipment.
2
Q
Who has the authority to deviate from clearance requirements and when are they allowed to do so?
A
- During a declared emergency condition, the Emergency Coordinator (EC) has the authority to deviate from clearance requirements.
- Only if compliance would result in significant hazard to personnel or equipment, or increase radioactive release off-site.
3
Q
State when double isolation criteria is required. What requirements must be met when double isolation is necessary?
A
- > 200°F or > 500 psig
- Requires an open tell-tale vent or drain valve between the two isolations.
- If double isolation boundaries are not practical or possible, additional measures should be used to provide adequate protection (removing flanged connections, or providing a vent or drain path where energy will be diverted to a safe location).
- Lethal Chemical System (none at PVNGS)
4
Q
When are Red Danger Tags used?
A
- Used on the isolation boundaries and at least one vent/drain.
- Can be on same component as a SOD tag.
- Vent/drain not required to be tagged open if:
- CTMT closure is compromised by the valve being opened. (Use a caution tag instead)
- Contamination concerns (Use a caution tag instead)
- Vent/drain valve is used for testing purposes (LLRT) (Use a caution tag instead)
- Potential for re-accumulation of hazardous stored energy no longer exists after the initial drain/venting operations (PW drained during outage)
- Only available vent or drain valve is going to be worked or removed
5
Q
What are SOD tags used for?
A
Single Owner Danger (SOD) Tags:
- Clearance used by a single work discipline to perform maintenance.
- Prevents equipment operation during maintenance which could endanger personnel or damage equipment.
- SOD Tag is equivalent to a Danger Tag.
- Issued to a SOD Tag qualified Acceptor
6
Q
When are Yellow Caution Tags used?
A
- Used where no danger to personnel is involved. States specific info, which shall be understood before operating the equipment.
7
Q
What are the MOV tagging requirements?
A
MOV tagging requirements:
- Fluid system boundary: tag power supply and local operator.
- Hand wheel NOT tagged when:
- Only electrical MOV work is required
- If manual seating of the MOV is not required, then MOVs inside containment do not require tags on the hand wheels during Modes 1 - 4 or when containment access is restricted.
8
Q
What are the check valve tagging requirements?
A
Check valves:
- NOT reliable as clearance boundaries.
- If a check valve is used, tags will NOT be hung at the check valve(s)
- Unit Operations Manager and Maintenance Department Leader authorization required.
9
Q
What are the requirements to use a failed closed AOV as a boundary?
A
Fail Closed AOVs:
- AOV is in the failed position before hanging the tag and closing the air isolation valve.
- Power supply and/or air supply are isolated and tagged.
Hand wheels or local operators are tagged.
10
Q
What are the requirements to use a failed open AOV as a boundary?
A
Fail Open AOVs:
- Manually jacked closed with an installed “jacking” (manual) device.
- Hand wheels or local operators are tagged.
11
Q
What are the requirements to use 13.8kV and non class 4.16kV breakers as boundaries?
A
- 13.8kV and non-class 4.16kV breakers
- Lowered or disconnected position
- Removed from the cubicle
- NAN-S07 13.8kV breakers in “DISC/TEST” position as indicated by the position indicator on the front of the cabinet with the breaker TEST lever inside the cabinet in the vertical, stored position.
- Breaker alignment checks which involve raising the breaker from its fully lowered position shall not be performed.
12
Q
What are the requirements to use a class 4.16kV or 480Vac breaker as a boundary?
A
-
Class 4.16kV breakers
- Lowered or disconnected position
- Raised between 1 and 2” from the floor (seismic)
- Removed from the cubicle
- Lowered or disconnected position
- 480Vac load center breakers: Disconnected position or removed
13
Q
What are the requirements to place clearance tags on fuses?
A
- Load Center Fuses:
- Remove fuse holder/block with fuses from the load center.
- Rotate fuse holder/block and reinstall in the non-connected (visible) position in the load center.
- Place tags on the fuse holder.
- All Other Fuses:
- Place tags as close to the fuse holder as practical or at a location obvious to anyone intending to replace the fuses.
- Best location: directly on fuse holder (Not MCC control power fuses, which should be placed on the door).
- Tags shall not be placed directly on the fuses.
- Fuses that are removed should be individually bagged and identified (clearance/tag number, panel location, UNID)
- If proper fuses cannot be located for reinstallation, submit a work request to ensure the proper fuses are installed.
14
Q
What are the actions associated with a missing, worn or illegible tag?
A
Missing Tag Actions:
- Immediately notify the MCR.
- Responsible Supervisor ensures:
- Work is stopped, establish positive control of the affected component, affected component is in the required condition.
- Replace with new tag, document, use CV
- Work Group(s) are notified that the tag has been rehung and stop work has been released.
Worn or illegible tag replacement:
- Replace with new tag, document, use CV
15
Q
What are the actions associated with a tag found unattached?
A
Unattached tag:
- Leave the tag as found and report it to the MCR.
- From an active clearance, Responsible Supervisor ensures:
- Work is stopped, establish positive control of the affected component, affected component is in the required condition.
- Tag is reattached using CV and documented
- Work Group(s) are notified that the tag has been rehung and stop work has been released.
- From a cancelled clearance, Responsible Supervisor ensures:
- Tag is not being used as a credited tag.
Unattached tag is destroyed.
