McCoy hesitated at the suggestion -- he didn't want to split up -- but when he started actually coughing a bit, he decided to take it far more seriously. He'd be no good to anyone if he collapsed in here. He dropped his hand from his mouth, where he'd had it in a vain attempt to filter the smoke and debris, and nodded.

"Don't push yourself, Spock." He pinned Spock with a glare. "I mean it. Don't even try. I can make do with whatever we can find down there if it gets too thick for you."