...For all we know, and despite the flimsiness and leakiness of the outer door, perhaps the entire transporter room can serve as a quarantine area if it is determined a tad too late that the landing party beamed up infected with mucous dreadspongitis. The quarantined team and the duty transporter operator would then have to be fed and cared for, possibly for an extensive period of time.
Timo Saloniemi
This makes a lot of sense to me in the tos universe