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Title: Loft duct project report

On October 16, 1992, during a routine examination of the loft of Building 332, the Building Coordinator observed cracks in the welds of the duct work that services the fume hoods for Rooms 1313, 1321, and 1329. Further examination revealed cracks in the weld of the duct work that services the gloveboxes in Rooms 1321 and 1329. Upon discovery of the cracked welds, facility management immediately took the following two actions: Because one crack in the fume hood exhaust extended 70% around the duct circumference, a 1-ton chain fall was used to secure the duct to the roof support structure to prevent the duct from falling if the duct completely fractured. The Facility Manager suspended plutonium handling operations in the gloveboxes and work in the fume hoods in the affected rooms until the situation could be thoroughly investigated. Building 332 is ventilated by drawing conditioned air from the building hallways into the laboratories, hoods, and gloveboxes. This air is filtered through two sets of high-efficiency particulate air (HEPA) filters before being exhausted from the facility. Figure 1 is a schematic of the typical air flow pattern for the facility. All affected duct work is located in the loft of themore » facility or pressure zone 4. This ducting is fabricated from 12-, 14- and 16-gauge, 304 stainless-steel sheet stock and joined by the Gas Tungsten Arc Welding (GTAW) process.« less
Authors:
Publication Date:
OSTI Identifier:
10177274
Report Number(s):
UCRL-ID--114533
ON: DE93018910
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Jun 1993
Research Org:
Lawrence Livermore National Lab., CA (United States)
Sponsoring Org:
USDOE, Washington, DC (United States)
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; DUCTS; FAILURES; FUME HOODS; GLOVEBOXES; VENTILATION SYSTEMS; WELDED JOINTS; CRACKS; STAINLESS STEELS; PLUTONIUM; GAS TUNGSTEN-ARC WELDING 420203; HANDLING EQUIPMENT AND PROCEDURES