Boeing Industrial Hygiene Internship 2023

Due to the proprietary information agreement signed with Boeing, I am unable to reveal the details of my decision and final recommendations.

Hexavalent Chromium (Cr6) is a long-recognized anticorrosion agent used in aircraft industries, despite its adverse health hazards. It is a respiratory carcinogen and poses risks to the skin, liver, eyes, kidneys, and respiratory system. At Boeing, Cr6 is used extensively when manufacturing for preventing corrosion on many aircraft parts. Elevated Cr6 exposures are found while applying primer, sanding, and performing filter changes inside paint booths. When applying chromium containing primers, employees may be exposed to Cr6 through ingestion, inhalation and skin exposure.

As an industrial hygienist, it is important to evaluate Cr6 exposures in aerospace, as its use is currently requred neccessary for production, and employee exposures may be elevated. Boeing requires training of all employees exposed to Cr6, regardless of whether their exposures exceed the PEL or AL.

The exposure assessment was conducted in paint booths and paint hangers classified as a Class 1 Division 1 regulated areas. The National Fire Protection Association (NFPA) and the National Electrical Code (NEC) classifies Class 1 as an area that could become flammable from a source due to existing liquids, vapors and gases. Cr6 sampling tasks and locations were selected through a process of gathering information about the work task and locations. Locations were selected based on the use of hexavalent chromium-based material during sanding and applying primer. This involved contacting the managers of the production areas and coordinating a time to conduct sampling.
Samples were collected analyzed in accordance with National Institutes for Occupational Safety and Health (NIOSH) Method 7600, utilizing 37 mm pre-weighed PVC filters in styrene cassettes (though filters were not weighed after sampling), which were analyzed using OSHA ID215v2 by an AIHA accredited laboratory. Sample media was sourced from an external laboratory. Gilian GilAir and Gilian5000 air sampling pumps were pre and post calibrated with a Dry Cal medium flow Defender at approximately 2 liters per minute (LPM). At the completion of air sampling, all the samples including field blank filters, were capped, and stored in a plastic bag with a chain of custody form and shipped to a laboratory for analysis.

Cr6 concentrations were relatively high in all the sampling locations. Factors contribute to the observed high exposures, including the effectiveness of existing control measures, the nature of the work, and how the work is being conducted.

Employees were selected based on the status of the production and the number of employees assigned to the job task. During slow production, there were few employees working, which impacted the number of samples to be collected.
There is no software to facilitate communication between production area managers and industrial hygienists for scheduling sampling times. Implementing a software interface to coordinate sampling could prove to be both time and cost-effective during the research process.

A huge thank you to my manager Devin Holck and my mentor Abigail for guiding me along my internship and challenging me with such a large-scope project. I extend my thank to the Safety team for their feedback and helping em grow as an industrial hygienist.