Say there are four lines of three forwards and three pairs of defensemen active for a hockey game - for each team. That’s 18 players per team. After every game a list is available that tracks the time on ice for every player - to the second. It’s unlikely that someone could be responsible for tracking two players at the same time, if they’re to measure to the closest second. So are there 36 guys in the stadium who are tracking ice time? Each one tracking just one player? Doesn’t seem likely. So, how is this task managed?
RFID chips on the uniform somewhere could pretty easily track them entering or leaving the ice.
Some quick looking around online says it’s done by hand. One person for each team. When someone enters the ice, they click on their name (or however the program is set up), when they leave, they tell the program they’re not on the ice anymore.
As for it being " every player - to the second", when you think about it, just because it’s ‘to the second’ doesn’t mean it’s accurate to the second. It could very well be off by a few seconds, say, if someone didn’t hit the button in time, and no one is going to notice.
Well, there’s only up to 12 guys on the ice at any given time during play, and two of them are the goalies, so that’s really only 5 on each side to track. There’s a whole team of off-ice officials that track everything that’s countable, and there is an off-ice official to track ice time for each team, so every time a guy hits the ice (or comes off), that official clicks on his name on his computer. It requires they pay close attention to what’s going on, but it’s not difficult.
Here’s an article: The Finer Points: How the NHL keeps track of ice time – Coincidental Minors Hockey
Sure they report by the second but if they are off by 5 or 10 seconds per shift who is going to notice? Even then shifts last about 2 minutes it would be easy to use a feed with the game clock that you can pause and slow down when people are entering or leaving. 1 guy to keep track of roughly when people enter and leave the ice and another look at the replay for more exact time. You could have the ice time stats very accurate only about a minute behind the game. I also would not be surprised that with practice you could be accurate to a few seconds without using replay
An interesting video about how similar statistics are generated for soccer in England.
The question does remind me of something I have been wondered for a couple decades now.
I keep meaning to see if they will track 6 men on the ice, when a team screws up and get too many men , and the refs don’t notice for a bit. But It’s too hard to derive it from the reported stats.
Shits haven’t been 2 minutes for years, (except Ovechkin refusing to switch off the power play :)) Most team start looking to change at 1 minute max , with a trend toward 45 seconds if possible.
Don’t feel bad. We’re all getting older.
And, now, all I can picture is Abe Vigoda as Detective Fish on Barney Miller, headed to the men’s room for half the episode. 
Can’t search easily from my phone, but we did this exact thread a few years back. A wonder if RFID chips in uniforms have made it to the NHL by now like if other sports.
Tell me about it :eek:.
Great typo. RFID chips are actually a really interesting idea. However, I don’t know enough about them to know if they would work in the NHL environment. They could certainly provide all sorts of data that isn’t currently available.
I want to know how they decide whether hockey players have “upper body” or “lower body” injuries when the trauma occurs right around the waistline. Or if they have a back problem, but what’s keeping them off the ice is pain shooting down their leg? 
Thats all coach speak. It often means nothing like what’s actually occurring. Just a way to keep the press from pinning them down and actually finding out what explains the player’s absence, although some coaches are slowly moving away from that anachronism. Here’s a nice article by David Haugh, discussing that very question. Some NHL teams hide injury information, but it might be hurting players – Chicago Tribune