The prevalence of Methicillin-resistant Staphylococcus aureus (MRSA) nasal colonization among Emergency Medical Services (EMS) personnel is not well studied. Methicillin-resistant Staphylococcus aureus colonization can be a health hazard for both EMS personnel and patients. The aim of this study was to quantify the prevalence of MRSA colonization among EMS personnel. This study will help the scientific community understand the extent of this condition so that further protocols and policies can be developed to support the health and wellbeing of EMS personnel. Hypothesis/ Problem The hypothesis of this study was that the prevalence of MRSA colonization among EMS personnel is significantly higher than among the general population. This was a cross-sectional study. A total of 110 subjects were selected from two major US Mid-Atlantic fire departments. Methicillin-resistant Staphylococcus aureus colonization was detected by nasal swabbing. Nasal swabs were inoculated onto a special agar medium (C-MRSAgar) with polymerase chain reaction testing performed. One-sided binomial distribution at the Study Size 2.0 Web calculator was used. Using the Web calculator, p (H0 proportion) = 1.5%; a difference (H1-H0) 'Δ' = 4.53% can be detected at α = 5% and power = 80% with N = 110. Samples were collected from 110 volunteers. Seven samples were positive for MRSA, resulting in a prevalence of 7/110 or 6.4% (95% CI, 1.8%-11%; P < .0003) compared with a 1.5% prevalence of MRSA colonization among the general population. There is evidence that EMS personnel have a higher prevalence of MRSA colonization than the general population. This can be a risk to patients and can be recognized as an occupational hazard.