Abstract
This project focused on the design of an accelerated aging system intended to evaluate the durability of pinniped identification tags used in marine mammal research. The system was developed in collaboration with the Cal Poly Humboldt Marine Lab and NOAA, under the guidance of Dr. Dawn Goley, to address the limitations of field based durability testing, which is slow, inconsistent, and difficult to reproduce. The primary objective was to create a repeatable laboratory testing framework capable of simulating multiple environmental stressors experienced by pinniped tags. This includes the accelerated tests of UV radiation, mechanical abrasion, temperature cycling and biological fouling.
The goal was to reproduce years of coastal exposure within weeks, enabling earlier identification of material weaknesses to improve life long tag performance. Dr. Dawn Goley served as the project client and liaison to NOAA research needs. While the team was not employed by NOAA, project direction was informed through client guidance, research priorities, and feedback related to marine life deployment conditions.
Our testing protocols and evaluation criteria were aligned with the practical challenges observed in existing pinniped tagging programs. The final accelerated aging system integrates multiple independent test processes, each targeting a key degradation mechanism:
● UV Exposure Testing: Controlled UV chamber used to evaluate color fading and surface degradation over increasing exposure intervals.
● Mechanical Abrasion Testing: The rock tumbler method was used to simulate extensive abrasion from rocks, sediment, and animal movement.
● Thermal Cycling: Alternating hot and cold water immersion to replicate rapid marine temperature fluctuations.
● Biofouling Simulation: Organic coating (cow manure) used to simulate microbial and biological surface exposure.
● SEM Analysis: Scanning Electron Microscopy used to compare baseline and exposed samples at the microstructural level.
These processes were selected through weighted decision matrices emphasizing functionality, repeatability, safety, cost efficiency, and ease of use.
Key Findings:
● Mechanical abrasion was identified as the primary contributor to structural degradation, causing surface pitting, edge rounding, and reduced readability.
● UV exposure resulted in visible fading and discoloration but did not produce measurable microstructural damage within tested durations.
● Thermal cycling caused minor cosmetic changes without compromising mechanical integrity.
● Biofouling primarily affected surface appearance, with no observable structural degradation.
● SEM imaging confirmed that physical wear, rather than UV or thermal stress, poses the greatest risk to life long tag durability.
The accelerated aging system provides NOAA and marine researchers with a reproducible and accessible testing framework for evaluating pinniped tag materials prior to field deployment. This system reduces the reliance on extensive field trials and supports data driven material selection for tag optimization. Recommendations for future work include abrasion resistant materials, protective coatings, and extended field validation.
- Appropedia Project Page: https://www.appropedia.org/NOAA_pinniped_tags_accelerated_aging_system
Date
Fall 2025
Department
Other
Other Department Affiliation
School of Engineering
Concentration/Emphasis
Material Degradation
Advisor/Professor
Dr. Dawn Goley, Professor Lonny Grafman
Citation Style
ASCE
Included in
Marine Biology Commons, Materials Science and Engineering Commons, Mechanical Engineering Commons