Containment Training. Jeff Hunter Hanford ALARA Center (509)

Transcription

1 Containment Training Jeff Hunter Hanford ALARA Center (509)

2 Hanford Information

3 Introduction Mission Support Alliance Contract for DOE-RL at Hanford. The ALARA Center supports Hanford, the DOE complex, commercial nuclear power, and anyone that asks for help.

4 Introduction The ALARA Center s focus is on: ALARA - Radiological Engineering; Safety and Industrial Hygiene D&D tools and techniques; and The D&D Knowledge Management Information Tool.

5 Containments: Glovebag, Tents, and More.

6 The Containment Process Containment design Is a containment needed or not? Installing a containment Removal of a containment Inspect Fabricate a containment Working in the containment Waste or reuse

7 Integrated Safety Management System (ISMS) The design, installation, and removal of containment enclosures is part of the Integrated Safety Management System.

8 Is a Containment or Other Engineering Controls Required? Discuss containments early in the planning process with all crafts represented. Know what hazards you want to control. Decide what type of containment is required: Tent, Glovebag, Sleeving, etc.

9 If a Containment is needed. Consider what crafts will work in the containment and what tools they will use. Consider space requirements. Consider interferences such as sharp objects, insulation, instruments, temporary shielding, etc. Know where you want the people positioned.

10 Plan for containment removal now! Plan for containment removal early on in the preplanning process. Plan to cover equipment and flooring with plastic, strip coat, etc. to reduce decontamination efforts. Consider false floors, waste dump sleeves, pass through ports, drain systems.

11 Containment Material Containment material is critical. Most tents are made of Pacifitex, but can be made of several materials. Glovebags are most commonly constructed of PVC and Polyurethane. Polyurethane is required if temperature less than 40 degrees (4.4 C). PVC can be modified in the field.

12 Polyurethane Construction Positive Aspects: Puncture resistant and cold tolerant. Negative Aspects: Will not accept glue or tape. Costs more and is harder to RF weld. Polyurethane has possible fire protection issues. Polyurethane is normally used when PVC is ruled out.

13 Other Construction Materials PVC Polyurethane Pacifitex Griffolyn Lexan Sheet metal Fire retardant plywood Other materials

14 PVC Example

15 Sheet Metal Example

16 Simple. even humble but effective!

17 Tent Example

18 Cutting Pipe in a Glovebag

19 Tent Example

20 Glovebag Example

21 Containment Design Design the containment s shape and size to accommodate your work. Is liquid going to be encountered? Are waste dump sleeves required? Consider using a false floor. Consider windows or removable top in your containment tents. Consider padding under the containment to preclude punctures, rips or tears.

22 Example of Tent Design

23 Example of Glovebag Design L R Left and Right Gloves 8, 12 Port Bag/Sleeve SS Service Sleeve Pass Through H 2 cfm Inlet Filter H 40 cfm Inlet Filter

24 Simple Glovebag Ventilation

25 Portable Ventilation Units for Tents

26 Ventilation Positive or negative ventilation can be used. Bring in ventilation high in the containment and remove it low. Design the air flow to go from clean to dirty. Make air flow move across and away from personnel.

27 Ventilation (cont.) HEPA filtered ventilation units should provide enough flow to keep airborne contamination in the containment. CFM of Vent Unit x 60 min = AC/hour Volume in ft 3 1 hour

28 Point Source Ventilation If localized ventilation is used to increase the amount of contamination captured, it should be positioned degrees from the worker to draw contamination away from the worker s breathing zone. Place the hose within one duct diameter and block air being drawn from unwanted directions.

29 Ventilation Dynamics You are down to 7.5% of flow one diameter away. 30% at ½ duct diameter away. If the duct is moved you may not have capture velocity.

30 When the Design is Complete Make a detailed sketch of the containment and ensure your team agrees on the design. Obtain signatures from interested groups, i.e., Fire, Radiological Safety, H&S, IH, Operations, etc. Contact a vendor or construct it yourself.

31 Vendor List Lance Industry Rich Industry RPS Frham Safety G/O Corp Inflatable Abatement Systems Look for asbestos removal companies

32 Hanford Plastic Shop

33 Lance s Plastic Shop

34 Construction

35 Glovebag With Frame

36 Lance s Instruction Installing Glovebag Gloves

37 Installing a 2 CFM Filter (for glovebags)

38 Installing a Drain

39 Better Drain System

40 Containment Frames Scaffolding Tubing (plastic or metal) Wood Stuck ups (plate and post glued to the wall) Tie to what is available Ensure the containment is well supported

41 Prior to Installation All sharp objects need to be padded. Cover exposed components not being worked on with plastic, strip coat, or tape to make decon easier. Consider support platform for glovebags. Consider padding under tents and glovebags. Build as much as possible in a non-rad zone.

42 Working with Containments Have a contingency plan for a breach. Review the contingency plan prior to critical work. Remember SWIMS, if necessary. Include void limits for RWP/work instructions. Test or inspect the engineering controls and containments each day before you use them.

43 Working with Containments Use good housekeeping practices. Watch for scope creep. Evaluate change. Include action levels for decontamination in work documents. Include decontamination levels necessary for containment removal in work instructions.

44 Containment Removal Have a plan. Decontaminate in a slow, deliberate manner. Keep ventilation running, if possible. Start top to bottom, clean to dirty, and easy to hard. Wipe and fold.

45 Hanford Example 244-AR

46 244-AR Elevation View

47 244-AR Problems Remove 19,000 gal from 4 Tanks The building was highly contaminated. The building ventilation system didn t work. The crane didn t work so there was no access to lower vaults through the 5 foot thick cover blocks. Holes had to be drilled through cover blocks to access tanks so they could be remotely cut open.

48 244-AR Problems (cont.) Building is narrow with little space for containment and support equipment. All material entered canyon through 4 foot airlock door. The work crew only had a few workers so installing a 70 foot long tent would have been difficult. If a portable ventilation system was installed, it would have had to been designed with a capacity of 5,000 CFM.

49 Work Planning Questions What engineered controls would work? What is best method to cut holes through cover blocks? What is best method to open the tanks? How do we remove the liquid from the tanks? How do we capture the contamination?

50 Work Planning Decisions Aerosol fog the building. Apply urethane coating over Capture Coating. A few workers assigned were familiar with containments, but not all. A Positive vent system was used.

51 The Work Plan Fix the contamination. Install containment in sections and ventilate the containment, not the canyon. Containment will consist of four 8 x 10 sections (over each tank) connected together with a passageway. Tents were installed by inflating them and then installing scaffold inside.

52 The Work Plan (cont.) Core drill two holes over each tank. Lower plasma arc to cut openings in the top of each tank. Lower submersible pump into each tank and transfer the liquid through a piping manifold to another tank located near 244- AR.

53 Example of Aerosol Fixatives Sound waves strike a liquid and create an aerosol fog that fills a space with a tacky glycerin coating Can be applied without entry.

54 Example of Urethane Application

55 Initial Survey After Fog

56 Tent Overview

57 Tent Installation

58 Tent Installation (cont.)

59 Tent Installation (cont.)

60 Tent Installation (cont.)

61 Ventilation Support Equipment

62 Core Drilling

63 Plasma Cutting

64 Questions? Let me Know if I can help. Jeff Hunter Hanford ALARA Center (509) jeffrey_l_hunter@rl.gov