Chlorhexidine Drying Time

Before a patient gets a spinal/epidural, their lower back is cleaned with an antiseptic solution diluted in alcohol called ChloraPrep. ChloraPrep must completely dry before starting the anesthetic procedure. It is not known how much time is needed for the solution to completely dry. The investigators aim to determine this. As the ChloraPrep dries, the alcohol is converted into vapour. The investigators will be using a PPBRae 3000 device to detect small amounts of vapours in the air. As the ChloraPrep dries it gives off less and less vapour. The investigators will use this diminishing vapour concentration to determine when drying is complete.