Som tam vendors will absolutely wreck tourists who don't specify spice levels. I've watched grown adults weep into their papaya salad because they thought they could handle "regular" Thai spicy. Here's your survival guide.

The spice hierarchy you need to memorize: Pet noi noi = very little spice (safest bet for beginners), Pet noi = little spice (still might bite), Pet = spicy (locals consider this mild), Pet maak = very spicy (will genuinely hurt), Pet maak maak = locals only (literal death level, don't try this).

Vendors automatically default to tourist-weak spice unless you specifically say 'pet tam thai' for authentic local heat. Even then, start conservative. The best som tam vendors are at Chatuchak Weekend Market (section 8) or any fresh market around 11am when they're making fresh batches. Price should be 40-60 baht.

Pro tip: Order with sticky rice (khao niao) to cut the heat, and always have a Thai iced tea ready. Trust me on this one - I learned by crying through a pet maak maak som tam in Thonglor and it was not pretty.