Potshell exfoliationPotshell exfoliation is a degradation mechanism in aluminum reduction cellsAluminum reduction cell, leading to the detachment of oxidized steel layers from the inner potshell surface. Observed across several Alcoa smeltersSmelter, this phenomenon could lead to significant degradation impact and safetySafety risks. Accumulated ironIron oxides behind sidewall blocks generate mechanical stressesMechanical stresses, leading to block cracking and compromising lining integrity. Critically, contact between these oxides and molten aluminumAluminum can trigger highly exothermic thermiteThermite reactions, threatening pot lifePot life and operational safetySafety. To address this issue, a structured approach has been developed to quantify exfoliation and evaluate mitigation strategies. Ultrasonic thickness measurementsMeasurements have been implemented across all sites, enabling detailed mapping of shell degradation and revealing patterns linked to pot design and thermal behavior. This paper presents the measurementMeasurements methodology, field data and analysis of exfoliation impacts and introduces several mitigation solutions currently under evaluation.