Clarification: Engineering in the arena?

No items with cooldowns longer than 15 minutes, and no consumables aside from bandages and conjured items can be used in the arena. Consumables include engineering items that are "consumed" as they are used, such as grenades and land mines.

These restrictions aren't specific to engineering and don't restrict all engineering items, but do limit the use of quite a few.

Q u o t e:
What about consuming a flask before the arena match begins?

Havent seen any answer to this

All buffs are removed when you enter the arena, you then have a while in a waiting area (just like the battlegrounds) to do whatever you need to do before the doors open and death comes barreling towards you.

Q u o t e:
Is this going to apply to potions too?

Poisons can be used in the arena.

Q u o t e:
Are normal potions out of the equation? And can I use elixirs in the starting area?

Is it a consumable and not a bandage or conjured item?