If an arena is interested in using the system, McCarthy’s group collects specific data to build the framework that determines the venue’s risk analysis. The information required is detailed: How does an arena ventilate bathrooms? What is the distance between bathroom sinks? What is the width of corridors where fans walk? What is the ticket-taking system and how long is the walk to seats?

The system was created after Delaware North, which owns the Boston Bruins and TD Garden and operates concessions at more than 50 arenas, sought a method to safely have fans attend games. It has been introduced to every team in the NFL, NBA, MLB, NHL and MLS.

“We want to give as thorough an analysis as we can,” McCarthy said. “Some stadia had their own plans … but they want a way of scoring how good the plan is. We came up with an interactive tool that can give you a score. Then you can ask, ‘What happens if we change something?’”

McCarthy’s interest in the project went beyond his role as Washington University’s chairman of the department of math and statistics. The native of Ireland is a sports fan whose interest in the Cardinals blossomed when he moved from Berkeley, California, to St. Louis and then found that people he followed as members of the Oakland A’s — Tony La Russa, Mark McGwire and Dennis Eckersley — joined the team.

McCarthy’s son, Myles, who works at the University of Illinois, also is involved.