A National Football League game has four 15-minute quarters with a halftime break of about 15 minutes.

For the Super Bowl, the halftime break is extended to 30 minutes because of the extravagant halftime show. Football is played in any climate from frigid Green Bay in Wisconsin to 90°F heat in Miami, Florida. Domed stadiums provide an escape in some locations but for the most part, players must play or sit on the bench for about three hours except for halftime spent in the team’s locker room. And while the games are won or lost on the field of play, a good argument can be made that what happens in the locker room at halftime has a profound effect on the game. The game’s “momentum” can shift from one team to the other with a fiery pep talk from the head coach. Players refresh themselves with sports drinks, energy supplements, and possibly performance-enhancing drugs. The air quality of the locker room is another great concern. Nearly 50 men in full uniform, some weighing more than 300 lbs., and the coaching staff pile into the locker room at halftime, and this will cause an immediate rise in humidity that the locker room’s HVAC system must react to. Most locker rooms are kept a bit warmer to prevent muscle cramps but moisture from sweaty bodies and uniforms and even a quick halftime shower can make for a rather uncomfortable environment. The key for any locker room’s HVAC system is good ventilation that moves the air from relatively dry areas to wet areas and then to the outside. This is important to prevent mold and mildew that can result in the bane of any locker room, the sweaty sock odor that evokes fond memories of our high school locker rooms.

Hybrid heating