Abstract: Agricultural activities have always been associated with hazards and injuries especially in oil palm plantation where the upstream tasks are majorly manual and labour intensive. Harvesters are exposed to danger when cutting the fresh fruit bunches (FFB) from the tree during harvesting. The height of the palm tree, as well as the quantity and weight of the FFB might injure oil palm harvesters severely where head injury is the main concern. However, due to thermal discomfort associated with working in an unpleasantly hot environment, harvesters tend to take off their safety helmet in which the act poses high risk to injury. Objective: This paper shows how an industrial design safety helmet shell was redesigned to improve its thermal qualities while still satisfying other critical safety helmet standards. Method: The design requirements were first gathered. Industrial design and mechanical design were attentively generated utilizing Computer Aided Design software. Structural and thermal analysis were simulated employing Computer Aided Engineering software, iteratively modelled and analysed for an optimally designed safety helmet to satisfy all the identified requirements. Notwithstanding that the absence of regulatory standard for thermal comfort, design detailing and engineering analysis effort was conducted to ensure thermal discomfort is significantly reduced to meet the targeted specification. Results: High fidelity prototypes were fabricated; field test was conducted to find the acceptability of the new helmet against the current existing helmets. The new safety helmet design was well accepted as there is a significance increase of acceptance level of parameter in day 1, day 3 and day 6 among oil palm harvesters. Conclusion: The well accepted newly proposed safety helmet for oil palm harvester not only solving thermal discomfort issue while being able to meet stringent safety requirements, but it also resolves all other addressed concerns. Safety helmet for use by oil palm harvesters should be modified to ensure the oil palm harvesters feel more comfortable, therefore encouraging them to wear them consistently during working, comply with existing regulations thus minimize injuries.