An emphasis on alpha-emitting nuclides at nuclear power plants has produced methods for assessing the relative hazard of alpha versus other species. From the relative hazards, or ratios, decisions on the level of effort for worker protection and monitoring are made. The Electric Power Research Institute (EPRI) has issued technical guidance on relative alpha hazard and action level beta-gamma to alpha ratios. This paper shows the development of the ratio concept from first principles and brings hard-to-detect species into consideration. Outcomes from the exercise of computational forms of the ratios are compared to the EPRI results and the differences are noted. Some discussion of the implications and advantages of the developed forms then follows.