Analysis of Size-selective Sampling Methods for Comparison with Welding Fume Metals Occupational Exposure Limits
Abstract No:
1421
Abstract Type:
Professional Poster
Authors:
B Regan1
Institutions:
1The Travelers Companies, Inc., St. Paul, MN
Presenter:
Beth Regan, MPH, CIH
The Travelers Companies, Inc.
The Travelers Companies, Inc.
Description:
Many occupational exposure limits (OELs) for welding fume metals are based on size-selective exposures categorized as total, respirable, or inhalable particulates. This poster presentation will analyze size-selective, side-by-side welding fume sampling results for comparison to established OELs. The information gained through this comparison will aid the IH professional in selecting the best method for welding fume sampling in accordance with the welding operations and will provide a better understanding of the composition of welding fume exposures.
Situation / Problem:
Because the OELs vary for different metals, it is common practice to sample using a total particulate method to capture data for the composition of the welding fume. This approach often requires making assumptions and using professional judgement when comparing the results to the size-selective OELs. One of the most critical size differentiation relates to manganese in which the ACGIH has published a Threshold Limit Value (TLV) of 0.02 mg/m3 for respirable sized particles. This limit is typically applied to the smaller manganese particles associated with the generation of fume created during welding, while a secondary TLV of 0.1 mg/m3 for inhalable sized particles considers the impact of larger sized manganese particles generated during tasks such as grinding. It is common for welding operations to include grinding tasks of varying frequency and duration which often makes the interpretation of results difficult.
Methods:
Size-selective samples for welding fumes will be collected on 5 microgram (µg) polyvinyl chloride (PVC) filters using a variety of samplers placed in the breathing zone of the welder outside of the welding helmet/hood. The air flow rates will be set according to the manufacturers recommendations for the sampling device and associated NIOSH analytical methods. The total particulates will be collected using a 37 mm single-inlet cassette (median particle size of 30 to 40 micrometers or microns), the respirable particulates will be collected using an SKC aluminum respirable dust cyclone with a 37 mm filter cassette or an SKC parallel particle impactor (PPI) sampler, and the inhalable particulate will be collected using the Institute of Medicine (IOM) sampler manufactured by SKC, Inc. The IOM sampler is a personal reusable filter cassette holding a preweighed 25-mm filter with a sampling head designed to better measure a worker's exposure to airborne particles. The gravimetric analysis for respirable particulates will follow the NIOSH 0600 method for Particulates Not Otherwise Regulated, Respirable. The gravimetric analysis for total and inhalable particulates will follow the NIOSH 0500 method for Particulates Not Otherwise Regulated, Total. The welding fume metals will be analyzed by Inductively Coupled Argon Plasma, Atomic Emission Spectroscopy (ICP-AES) under the following NIOSH 7300, Elements by ICP (Nitric/Perchloric Acid Ashing).
Results / Conclusions:
The results of this study will indicate the size variability of metals exposures during metal fabrication tasks including welding, grinding and fitting for comparison with size selective occupational exposure limits. The information gained through this comparison will aid the hygiene professional in selecting the best method for welding fume sampling in accordance with the welding operations and will provide a better understanding of the composition of welding fume exposures. During general IH surveys, the resources available for monitoring welding fume exposures does not often allow for collecting multiple samples to address size-selective OELs.
Primary Topic:
Sampling and Analysis
Secondary Topics:
Exposure Assessment Strategies
Co-Authors
Please add your co-authors below. Co-authors are listed for professional courtesy and will not be communicated with regarding the decision notification or any on-site logistics, if accepted. Only the primary presenter listed is expected to attend and present the content on-site.
Acknowledgements and References
List any additional people who worked on the project or provided guidance and support along with details on the role they played in the research. (Please include first name, last name, organization, city, state and country).
Gary Brockway, CIH, Industrial Hygiene Specialist, The Travelers Companies, Inc. Los Angeles, CA
Josef Chrzanowski, Production Group Leader, Risk Control IH Laboratory, The Travelers Companies, Inc. Windsor, CT
Joseph David III, CIH, CSP, Senior Industrial Hygiene Specialist, The Travelers Companies, Inc. Dallas, TX
Teresa Dyson, Industrial Hygiene Specialist, The Travelers Companies, Inc. Chicago, IL
Cydney Green, Risk Control Associate - IH, The Travelers Companies, Inc. Windsor, CT
Torey McLaren, CIH, Industrial Hygiene Specialist, The Travelers Companies, Inc. Hartford, CT
William Shoemaker, CIH, Industrial Hygiene Specialist, The Travelers Companies, Inc. Charlotte, NC
Thomas Surveski, QA Manager, Risk Control IH Laboratory, The Travelers Companies, Inc. Windsor, CT