[Hallb-engineering] Fwd: Lesson Learned "PHY-15-1119 Small Fire as a Result of an Overheated Warming Element within the Q1 Magnet"
tilles at jlab.org
Wed Jan 13 08:04:54 EST 2016
----- Forwarded Message -----
From: "Tina Johnson" <cjohnson at jlab.org>
To: "Tina Johnson" <cjohnson at jlab.org>
Sent: Tuesday, January 12, 2016 4:00:06 PM
Subject: Lesson Learned "PHY-15-1119 Small Fire as a Result of an Overheated Warming Element within the Q1 Magnet"
Jefferson Lab Lessons Learned : Print Lesson
PHY-15-1119 Small Fire as a Result of an Overheated Warming Element within the Q1 Magnet
Statement of Lessons Learned
1. Although hard to accomplish, maintaining a clean and organized work space will aid in the workers ability to navigate to various hard to reach areas within congested work areas.
2. Whenever possible, purchases systems as a single unit. This will eliminate the possibility of getting the wire connected improperly during the installation process.
3. As per your Fire Extinguisher training, when you see or suspect a fire, pull the closest fire alarm in a timely manner and the appropriately trained personnel will respond to your area.
4. Whether temporary or permanent systems, design and fabrication need to conform to established engineering principles including the identification and mitigation of hazards.
5. Conformance with the lab procedures for fabrication and modification of electrical equipment that is not listed by a Nationally Recognized Testing Laboratory (NRTL) will ensure that SME's review is completed so that potential hazards can be identified and mitigated.
Discussion of Activities
The heating element thermostat overheated the lexan-like cover around the Q1 magnet connections causing a small fire. The Engineer was testing the power supply, and noticed that the surge protector supplying the heating element controllers had tripped. He reset the surge protector and proceeded with his testing. Around 3:00 pm welders performing work below noticed water dripping. When they looked up to investigate, they observed a glow, and one of the technicians immediately responded upstairs with a fire extinguisher to put out the fire.
After extinguishing the fire, technicians put the magnet in a safe state and took a closer look at the issue. It appears that the lead mass flow heaters thermometers were connected improperly. This system set-up was done in February and parties are not aware of any changes that were made to this set-up since then. The area was marked off and technicians are currently working to repair the damage and label the involved parts to ensure this does not happen in the future.
Direct Cause: The overheating of the poly guard was a result of the temperature probes and thermostat controls (TC) not being properly matched. The misalignment of these components allowed the cartridge heater (HTR) to remain in an "on state" causing heating of the surrounding piping.
Root Cause: Design of the system was less than adequate (LTA)
C1 - The cartridge heater and the thermostat control were not hard wired together as are the existing systems.
C2 - The heater system set up was temporary
C3 - The heater system temporary set up design was not reviewed
C4 - The temporary heater system fabrication was not in accordance with the ES&H Manual Chapter 6240 Electronic Equipment - Construction and Modification Safety
C5 - Installation/re-installation was not QA to verify proper alignment of the heater and thermostat control
C6 - Human Error - person unknown connected HTR 1 with TC 2 and HTR 2 with TC 1
C7 - All components look identical and are not labeled or otherwise identified and were installed in close proximity to one another
C8 - Work space is compact making it challenging to easily visually verify component matching
Poor Work Practices that need addressed:
1. Although not a contributing factor to the fire several electrical deficiencies were noted during the investigation e.g. surge protectors (relocatable power taps) being used not as listed or designed, circuits being potentially overloaded (2 heaters into 15A rated surge protector), failure to provide adequate over current protection (15A surge protector plugged into a 20A receptacle fed by a 30A circuit).
2. Fire alarm for the building should have been pulled before fighting the fire. Although the fire was small training expectations is that the fire alarm be pulled to facilitate evacuation and summon fire SME.
Extent of condition Check :
1. Check Hall C for other less than ideal electrical set-up with regards to the 30amp pig tails.
2. The Design Group will evaluate and update their desktop procedures to include a review by an electrical engineer and other pertinent subject matter experts during the design phase.
3. Identify the two heater system elements and color code them to ensure that if it is ever disconnected, you can visually inspect and reconnected the elements properly.
4. Re-Design the heater system fabrication to ensure that it is in accordance to the ESH manual Chapter 6240.
5. Have electrical receptacles properly sized and installed for these magnets. Ones that will handle the load and replace the need for surge protectors.
JLab Preventive Measures
1/12/2016 3:34:32 PM by Johnson, Tina
The above have been approved for distribution. Please share lessons learned within your work group.
Summary Lesson ID: 928
Doc ID: 2016-JLAB-928
Safety Related: NO
Originator: Johnson, Tina
Issued: 1/8/2016 12:10:35 PM
Approved By: Johnson, Tina
Approved On: 1/12/2016 3:34:32 PM
Source: TJNAF NE
Contact: Paul Collins
Queued Emails: 0
Sent Emails: 0
Viewings: 7 times Attachments
* Other: Design and Review of Design and initial setup less than adequate
* SAF108: FIRE SAFETY
* *Division Safety Officers (DSOs)
* *Safety Wardens
* *DOE Notification
* *ESH&Q Liaisons
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