How do walk-in freezers not give people hypothermia? [they do]

[SpeedOfLightYagami]

I'm always surprised that this never happens when I need to grab some meat at BJ's.

 

[Ibix]

Because you aren't in there very long and it takes a while to cool down to the point you're in danger. You wouldn't want to be shut in one for long, though (I expect Health and Safety will require modern ones to be openable from the inside in reality, although I've never had occasion to check.

 

[Baluncore]

People who work in cold stores wear polar survival gear, and sometimes get frost bite because there is a small accidental gap in their clothing.

On one occasion, I stood still in a -40° cold store, wearing shorts and a T-shirt. Over the first minute I felt the cold penetrating to my bones, then when I lost sensation of my flesh and could only feel my skeleton, I escaped to 30°C. Being chilled to the bone took on a new meaning. I was young, and it was foolish, but anatomically enlightening. It is not something I would recommend others try.

 

[Dale]

It is absolutely a hazardous environment. If you were to remain inside for an extended time then you would suffer from exposure

 

[Lnewqban]

... I expect Health and Safety will require modern ones to be openable from the inside in reality, although I've never had occasion to check.

It is a standard safety requirement.
Please, see:
https://www.kasonind.com/index.php/products/latches_and_locks/walk_in/inside_realeases

Even if the mechanism fails or the door is blocked, building codes require that means to shutoff evaporator are accessible from inside the freezer.

 

[256bits]

Forensic scientist Howard Cannon says 60 people die from walk-in freezer incidents per year. He says some freezers do not have basic safety features, like a panic button to inform anyone outside of the freezer when someone is stuck inside.
https://www.insideedition.com/louis...-getting-trapped-inside-freezer-lawsuit-85922

I came across the above statistic while searching for the case last year or so of a young woman who died in a freezer, ( I think in a Walmart, but not exactly sure ).

 

[gmax137]

At my first restaurant job (summer of '72 ?) we had a walk in, and it had a big plunger type knob to open the latch from inside. That was over 50 years ago, and the walk in was probably 10 or 20 years old then.

 

[oz93666]

People who work in cold stores wear polar survival gear, and sometimes get frost bite because there is a small accidental gap in their clothing.

On one occasion, I stood still in a -40° cold store, wearing shorts and a T-shirt. Over the first minute I felt the cold penetrating to my bones, then when I lost sensation of my flesh and could only feel my skeleton, I escaped to 30°C. Being chilled to the bone took on a new meaning. I was young, and it was foolish, but anatomically enlightening. It is not something I would recommend others try.

-40!!! .... Why do freezers have to be that cold? My understanding is that at freezing point all decomposition of meat ,or anything comes to halt.

 

[Baluncore]

Why do freezers have to be that cold?

Because they store ancient ice cores, not food.

 

[oz93666]

Because they store ancient ice cores, not food.

Why do ice cores need to be so cold?

 

[Baluncore]

Why do ice cores need to be so cold?

Because warmer ice flows, and bubbles of historical air in the ice can move.

 

[oz93666]

Because warmer ice flows, and bubbles of historical air in the ice can move.

Oh ... I understand glass is an amorphose solid , no molecular bonding , just a very very thick syrup ...
And a quick search reveals ice is also an amorphouse solid ...
Thanks ... that's something I've learnt today.

 

[Baluncore]

And a quick search reveals ice is also an amorphouse solid ...

Old ice is not amorphous, it is a crystalline solid, like a rock made from crystals of H₂O.

Glaciers flow, and skates glide, because ice melts where local pressure is applied. Colder ice requires higher local pressure, before it will melt, flow and recrystallise.

Ice in storage is subjected to a minimum contact pressure. That ice is most stable at lower temperatures, where those pressures will not be relieved by local melting.

 

[sophiecentaur]

Colder ice requires higher local pressure, before it will melt, flow and recrystallise.

I remember the 'regelation' demo at school when a wire is slowly pulled through a block of ice.

Like an idiot, when I was a lad I went into a freezer room and shut the door behind me. The fan kicked in and I was suddenly in an Antarctic storm. I was relieved to push the bar which released the door. Of course, the light had gone out which made it even worse.