Overview
Welding Emissions (2000-922)
Project Team:
- Edison Welding Institute
- General Dynamics Electric Boat
- ESAB Welding Products
- Ingalls Shipbuilding
- General Dynamics Bath Iron Works
- General Dynamics NASSCO
- Lincoln Electric
- Naval Surface Warfare Center - Carderock (NSWCC)
- Kura Environmental Consulting
April 2000 - February 2003
NSRP ASE Investment: $862K
Industry Investment: $993K
Objective:
Developed and demonstrated improved process and engineering controls that reduce worker exposure, result in cost avoidance, and have minimal impact on productivity and the cost of construction or repair.
Summary:
Led by Edison Welding Institute with six shipyards on the team, this project identified a number of options to reduce worker exposure to welding and cutting fumes while simultaneously sustaining shipyard productivity and minimizing added cost from compliance with the new regulations. Aware that the Occupational Safety and Health Administration (OSHA) was developing a new occupational exposure standard for hexavalent chromium, this project was launched to find ways to reduce worker exposure to weld fumes, a significant source of hexavalent chromium in the workplace. Compliance with the proposed rule was expected to cost the industry an estimated $600M annually. While there are many approaches to the control of worker exposure to hexavalent chromium and manganese, this project identified the following engineering controls to minimize exposure:
- Process modifications
- Improved local exhaust ventilation
- Substitution of alternative materials
- Isolation through mechanization and automation
The effectiveness of these controls was verified through laboratory tests and worker exposure tests in shipyards. Test results indicated that these methods are capable of reducing hexavalent chromium and manganese exposure for mild and low-alloy steels to within OSHA’s targeted Permissible Exposure Limit range, at much less cost than the anticipated proposed standards would entail. These methods can also be more effective than exposure control using only respiratory protection. The shipyard project participants have implemented these process modifications and engineering controls to varying degrees as appropriate for their specific needs.
Examples include:
- Northrop Grumman Newport News and GD Electric Boat implemented process modifications
- Northrop Grumman Ship Systems utilized new improved flux-core arc
- welding electrodes that provide less spatter and smoke
- Bath Iron Works employed improved local exhaust ventilation
- GD NASSCO used isolation through mechanization and automation
The project team also coordinated work with other NSRP activities. One area of coordination was with the NSRP-funded “World Class U.S. Material Standards and Parametric Design Rules.” This project may be able to incorporate (where possible) design guidance for material selection that will minimize potential welding fume problems with hexavalent chromium. The second area was coordination of training materials with the NSRP Crosscut Panel.
Key Deliverables:
Final Report – Approved for public release; distribution is unlimited
Point of Contact:
Harvey Castner, Edison Welding Institute