<p>Health care waste generated by medical activities provides an urgent need for efficient management and disposal. Its diverse composition, including infectious materials and hazardous substances, demands specialized handling to reduce health and environmental risks. As a result, selecting the most suitable health care waste treatment technology for decomposing the waste presents a significant challenge. Therefore, in this paper, we propose group decision-making method within the <i>p</i>,&#xa0;<i>q</i>-quasirung orthopair fuzzy context to select the optimal health care waste treatment technology. To begin, this study proposes new addition operation and scalar multiplication operation of <i>p</i>,&#xa0;<i>q</i>-quasirung orthopair fuzzy numbers using Yager’s t-conorm and t-norm. Afterwards, this work proposes the <i>p</i>,&#xa0;<i>q</i>-quasirung orthopair fuzzy Yager prioritized weighted arithmetic aggregation operator for aggregating <i>p</i>,&#xa0;<i>q</i>-quasirung orthopair fuzzy numbers based on the proposed operation laws. This study also demonstrates several features of the proposed aggregation operator. Moreover, using the proposed aggregation operator, this study presents a novel group decision-making method for the <i>p</i>,&#xa0;<i>q</i>-quasirung orthopair fuzzy number environment. Furthermore, this study considers a case study that demonstrates the proposed group decision-making method’s applicability by selecting the optimal health care waste treatment technology for efficient management and disposal of health care waste. In this case study, this work considers five health care waste treatment technologies: “incineration,” “plasma pyrolysis,” “autoclaving,” “microwaving,” and “chemical disinfection” as alternatives. Finally, this study considers two illustrative numerical examples to show the superiority and validity of the proposed group decision-making method over the existing group decision-making methods.</p>