If your phone is off, then emergencies don't happen. That's how it works. Simple cause and effect.
Seriously, if I were playing a match and my husband needed to reach my captain, he couldn't do it if a million dollars were riding on it. I do tell him which facility I'm going to, so he could reach me in a massive emergency by calling the front desk. It had better be something more interesting than a nose bleed.
I did have one emergency that happened while I was playing a match. When I play, I leave my son (then 12) at home alone. The amount of time he spends alone varies -- his dad tries to time his arrival to coincide with my departure, or one of his older sisters might breeze through.
Anyway, on this night I decided to order a pizza delivery for him. I ordered two large pizzas so everyone could eat when they showed up. The delivery guy was late, so I greeted him the driveway, paid him and handed the pizzas to my son. I then left for the match.
When I came home, the whole house smelled of smoke.
Apparently, my son took the pizza boxes inside, served himself, and put the two large cardboard boxes in the electric oven to keep them warm. He turned on the oven to 200 degrees. One of the boxes touched the element and started to burn.
Son, being downstairs engrossed in Facebook, was unaware of this fire until the smoke alarms started going off. He called his dad, who advised him to -- and I am not making this up -- take the boxes out of the oven and put them on the back patio. There were two mostly consumed cardboard boxes on the patio table, with ashes and hunks of partially burned cardboard on the tile below the table.
Dad definitely blew the "What to do in case a pizza box catches fire" test, but I am sure he could handle a nosebleed.