What to do when you witness a meltdown

Crackle had a meltdown today. A full-blown autistic meltdown. He doesn't have many of these anymore, because I'm really good at managing his environment. But today at about 4:30, he lost his marbles. I don't know what sparked it, but he lost it and started screaming, crying, and wailing. Hysterically. Loud enough to be heard for at least a km. Not exaggerating. Anyway, that's not the point.

I got him into his shoes, his brother into clothes and shoes, and took them out to the van (car rides calm Crackle down). When I opened the front door, there were two men standing there. They were from the company doing an engineering report for our strata. Anyway, I smiled, they smiled, and the one guy said, "How's your little guy doing?" I said, "Oh, okay. It's an autistic meltdown, is all. We'll go for a drive and he'll be okay." The guy smiled, nodded, and said, "And how are you doing?" WOW. I said, "I'm okay. He doesn't do this much any more. And I like car rides too, so it's good." The guy smiled and said, "Okay! Have a good one." [edit: Then, after I took 4 steps, gobsmacked by his class and kindness, I stopped, turned around and said, "Thank you for that. I really appreciate it." He just smiled and said, "No problem."]

That. Is. Awesome. That just doesn't happen. Like ever. It's almost always the stink-eye. Or "shut that kid up" or "What's his problem?" This is exactly what to do when you see a kid losing it. Ask Mom how he's doing. Ask her how she's doing. And if she doesn't seem to need help, smile and say 'have a good day'. If she seems to need help, say, "Need help with anything?" And then take no for an answer if that's the answer. This guy did it perfectly.