A pitch pipe is a relatively simple instrument--identical to a harmonica with a series of blow holes that when activated vibrate a reed that produces a pitch. Because of the simplicity of the instrument, it is very sturdy and doesn't require too much upkeep. However, a few simple steps to preserve its longevity and maintain accuracy in pitch are recommended.
Keep the pitch pipe in its case whenever possible. Most pitch pipe cases are plastic on the outside with some form of padding (rubber, foam or felt) inside to protect it from any jarring motions. If the case does not have padding, purchase some from a hardware store and glue it into the case.
Avoid putting the pitch pipe in pockets. Pocket lint can get inside the blow holes and block the airflow or damage the internal reed.
Run warm water through the pipe, occasionally, to clean it out. Do not use any soap or cleaning agent as it can damage the internal structure.
Clean the blow holes by pouring some rubbing alcohol over a cotton swab and rubbing the swab over the holes.
Do not use an abrasive sponge to clean the pipe as it will mark the surface.