I go to a really nice gym. They have not only a large weight room with a ton of nice equipment, but also two swimming pools, two full-size basketball courts, several racquetball courts, a rock-climbing wall, and two large rooms for aerobics classes and such. They also have a full-service child-care center, a small cafe, and a place where you can get massages and facials. (The only reason I get to go there is my wife works at a place that provides a family gym membership to all its employees.)
The locker rooms are really nice, too. They have both dry-heat and steam saunas, plus they provide towels so you don't have to bring your own. Recently, several of these signs were posted in the locker rooms: "Holy cow," I thought, "17,000 towels a day, that's a lot of towels!" I figured a lot of people must really be wasting towels and that it was a good thing that the gym owners posted those signs so those towel-wasters would wake up and stop wasting so many towels. I was also feeling pretty pleased with myself, because I only use two towels every time I visit.
But then I got to wondering just how many towels, on average, people were actually using. It would depend, of course, on how many people came thru the gym on an average day, but I didn't have that information. I asked at the front desk if they could tell me, but was told that that information was proprietary and they weren't allowed to give it out. (I guess they don't want potential competitors to know how many people are using their gym?)
So I started thinking about it. If 1,000 people a day came thru the gym, that would be an average of 17 towels per person, which would be absolutely outrageous; nobody needs to use 17 towels when they go to the gym. But if, say, 5,000 people a day were coming thru the gym, that would be an average of only 3.4 towels per person; maybe the people who were using 5 or six towels per visit could stand to cut back, but 3.4 towels per person didn't seem outrageous. On the other hand, I couldn't imagine that 5,000 people a day were coming thru the gym; heck, 1,000 people a day sounded high to me. Without knowing the actual number of people who came thru the gym, I couldn't figure out whether we were using too many towels, and the gym owners weren't telling. So I did the next best thing: I counted them.
No, I didn't actually count every single person coming into the gym one day, but I did count every person coming into the gym for 30 minutes one afternoon, roughly between 3:30pm and 4pm. During that time, 115 people, adults and children, walked thru the doors, which is approximately 230 people an hour. The gym is open 24 hours a day, though I suspect there are a lot fewer people that come during the late night and early morning hours. So I figured that between 6am and 9pm, 230 people an hour would come thru, and between 9pm and 6am only about a quarter of that, or 58 people an hour, would come thru. Thus:
230 ppl/hr x 15 hrs = 3450 people
58 ppl/hr x 9 hrs = 522 people
3450 + 522 = 3972 people per day
17,000/3972 = 4.3 towels per person
One could interpret these numbers different ways. Since I only use two towels per visit, 4.3 seems a little high as an average, but I typically only go to workout in the weight room and use the steam room and then take a shower. If someone's going to spend several hours at the pool, plus maybe play some basketball then take a shower, maybe using five or six towels isn't so outrageous.
There are other things to take into consideration as well. It's not clear from the posted sign whether the 17,000 number refers to full-size towels only, or includes the small hand towels which many people use to wipe sweat from their faces and hands during their workout. If the 17,000 includes hand towels, the 4.3 average towel number starts to sound even more reasonable. And of course, my numbers are only an estimate based on a single 30 minute sample on a single weekday afternoon; the number of people coming to use the gym no doubt varies from weekdays to weekends, from one week to another, from one month to another, etc.
The larger point, however, is that being told that this facility provides 17,000 towels per day doesn't give us enough useful information to determine whether we're using too many towels or not. I suspect that it costs a good bit of money to wash and dry all those towels every day, and the owners were hoping to get us to cut back on our towels usage by posting a number that sounds really big, thus generating the kind of "Wow, that's a lot of towels" reaction that I initially had. It would be even better, however, to actually know how many towels we're using on average. Then we might be able to decide whether we're really using too many.
Update: Reader Jennifer was somehow able to get the gym staff to give her the information that they made me work for. (Maybe she said please?) The official word is that the average person at my gym is using 5 full size towels per visit, and yes, I agree that seems a little high. For those keeping score at home, if the average person is using 5 towels per visit, and a total of 17,000 towels per day are being used, that means approximately 3,400 people are coming thru the gym every day.