This paper presents a method for designing a customized ergonomic office chair backrest aimed at improving ergonomic chair user posture and long-term health. Given the importance of ergonomics in workplace settings, this study leverages 3D scanning and additive manufacturing to create personalized cushions that conform precisely to individual anatomical shapes, aligning with ergonomic standards. The process begins with high- resolution scans of both the user's back and a standard chair backrest, followed by cushion modeling in Blender to ensure exact fit and support. Additive manufacturingwasselectedfor cushion fabrication, using a TPU material with an optimized internal structure to enhance comfort. Results indicateanotableimprovement in posture alignment and comfort, verified through comparative scans before and after customization. The custombackrestalso encourages proper posture through a postural retraining effect and provides a high level of hygiene due to its nonporous material. While this customization method is best suited for individual users rather than shared work environments, it offers a viable, cost-effective solution for ergonomic enhancements in office seating.This study investigates the feasibility of integrating Internet ofThings(IoT) technology into office chair design to enhance user comfort and ergonomics. By examining current office chair designsandIoTtechnologies, as well as conducting user testing, the research evaluates the efficacy of a proposed IoT- enabled office chair prototype.Utilizing the System Usability Scale (SUS) for usability assessment, the study provides immediate feedback on posture andcomforttousers. The findings from this research inform adjustments to the prototype, enabling it to offer an enhanced user experience. Throughtheevaluation of the prototype's effectiveness and discussions on potential advancements in IoT-enabled office chair design, thisstudycontributes to the evolution of smart office furniture for improved workplace ergonomics and user satisfaction.The purposeof thisstudywas to determine if ratings of discomfort differ over time between two ergonomic chairs of thesame approximate cost. Twentyparticipants from a metropolitan university sat on two types of ergonomic chairs for 90 minutesin each of two sessions whileperformingtyping, reading, and writing tasks. Repeated measures three-way and two-way analysesof variance were used to examine theeffect oftheergonomic chair design on rating of discomfort. Data were collected usingthe General Comfort Rating Scale (GCRS) andtheBodyPartDiscomfort Rating Scale (BPDRS), which were administered at0, 30, 60, and 90 minute marks of each session. The results revealed:1)discomfort was not related to the type of chair, 2)discomfort increased over time, 3) discomfort was influenced by the taskperformedwhile sitting, 4) discomfort level decreasedwhen switching between different chairs, and 5) most discomfort was reportedinthelowback and lower arms. Keywords: Ergonomics , Ergonomic Chair Design , Occupational Health