" - thank you."

"You could just say that the wizard spell Scourgify counts," he says. "As whatever your cleaning procedure does."

"What does it do?"

"Cleans things. Do you have a storage closet you want turned into four more bedrooms, or something -"

"Yes, sure," Nertel says, showing him one. "How does it clean things."

" - magic."

"How clean are the things after," says Isama.

"- entirely clean?"

Nertel frowns. "There are no surviving bacteria and no dust motes and no traces of debris - how does it decide what counts as requiring cleaning - Can you cast it on a petri dish for me - can you cast it on thirty petri dishes for me -"

"I don't know what a petri dish is but presumably."

"Then I'll set that up. It'll take me a couple hours, though -"

"Oh, this'll take me a couple hours, I've never given a house four new bedrooms before I usually just cheat at fitting my books on my bookshelves."

And he gets to work.

Some of the kids watch curiously.

He moves his wand very carefully and mutters things and stretches the wall and stretches the wall further and mutters more things and moves his wand more. 

Nertel gets a spread of substances to check how Scourgify interacts with them and starts incubating some bacteria in her tabletop incubator (she's not even a biologist, it's just for fun) and passes around lists of desiderata for people to decide what would make them comfortable relying on wizard cleaning spells in place of normal decontamination and also in place of fullscale red decontamination.

Well the real sticking point with the latter is the stem cell thing.

"I don't know if there's magic that'd do the equivalent of that, you could ask Miranda."

Miranda doesn't know what a stem cell is but she can do the blood transfusion part.

Nertel can explain what the stem cell thing is and what it's supposed to accomplish - "bone marrow transplants achieve that too but they are really expensive."

"...there is a potion that can regrow bones entirely, maybe Karen could figure something out."

Sigh. "We'd really appreciate it."

"No problem. She might want hair samples or something."

"From us or from reds - the ones here are all clean -"

"I really don't know but that is probably not a potionally useful difference."

"Well, she's welcome to ask us for anything she needs."

"I will let her know."