In forensic science, trace evidence establishes links between victims, suspects, and crime scenes. Head hair commonly serves as a reliable biomarker because it contains a permanent record of elements from an individual's body. By substituting CF4 reaction gas for polytetrafluoroethylene powder, this work modifies and re-optimizes a previous method for determining the sex of humans by directly analyzing hair samples via electrothermal vaporization with detection by inductively coupled plasma optical emission spectrometry. Hair samples were washed in portions of doubly deionized water, dried, and ground into a fine powder before analysis. Data processing included the use of an Ar emission line to compensate for sample loading effects on the plasma via point-by-point internal standardization. The peak areas were then integrated before multivariate analysis by principal component analysis (PCA) and linear discriminant analysis (LDA). Using the same predictor elements as the original method (Mg, S, Sr, and Zn), LDA and PCA remained effective at accurately predicting the sex of female and male samples despite using a different chemical modifier and instrumental operating conditions, indicating method robustness. This work thus offers an alternative method that uses a more affordable and accessible carrier agent at no cost to the original method's reliability.