Hermione began filling in the form, glad that she knew what she was doing. She didn't hide what she was writing from him, not worried about what he saw.
"I suppose if it ever came to it and I needed a blood transfer, they need to know what blood type I am so they can get the right blood in me. Though I hope that's not the case with this," she told him absentmindedly.
She kept her eye on the form until he asked his next question, so she turned to answer him. She noticed how uncomfortable he looked, so offered a smile to him, slowly reaching out to squeeze his hand.
"It's disinfectant. It kills germs, helps prevent infections when the patients are weak already. Without it, the germs and viruses could easily make patients worse, and I suppose there's a chance that those who aren't patients would become ill. With it, there's less a chance of it happening." She squeezed his hand again, before turning back to the clipboard. "I don't really notice it much, I grew up seeing my parents at work and I guess I got used to the smell of disinfectant."