Yes. Any minimally processed vegetable should be refrigerated.
Yes, lettuce should be refrigerated to maintain its freshness and prevent wilting.
Yes, lettuce should be refrigerated to maintain its freshness as cold temperatures help slow down the wilting process and preserve its crispness.
Lettuce retains quality and nutrition best if kept refrigerated. Minimally processed lettuce should be treated like any other potentially hazardous food and should be kept refrigerated.
No. It does not.
Cardboard boxes by truck or rail, refrigerated containers
Yes you will need to refrigerate after opening, but it doesn't need to be refrigerated if still sealed.
Warm temperatures allow certain bacteria to multiply very fast. It depends what kind of bacteria are on the iceberg lettuce as to whether or not it would be dangerous. If the lettuce has been contaminated with pathogens, it could be dangerous whether or not it has been refrigerated.
It's supposed to be served chilled, so yes.
In a sealed, refrigerated container, you could store it for months.
Yes, lettuce can be left out at room temperature but this will make it go bad faster if it is not kept in a sealed bag. Although lettuce goes bad pretty quickly anyway, in the fridge or not.
No. Vacuum seals keep out air, so the bacteria cannot grow.
Yes, it will wilt without keeping cool.