The Inhalation Tower system’s purpose is to expose subjects to a wide variety of compounds, so the inside of the tower, adaptors, nose-seals, outflow tubing, and accessories will all naturally be exposed to that same compound. Unless you are running multiple consecutive runs with the exact same compound, or perhaps a higher concentration of a previous compound, you will want to disassemble and clean the entire system between each exposure.  This information can also be found in the Inhalation Tower Application Manual.

Depending on the type of exposure, users may want to run the system consecutively without disassembling and cleaning every component.  The following list of components are necessary to clean to prevent cross-contamination between exposures (note that your Inhalation Tower system may not include all of these):

• Nebulizer Head
• Plenum
• Diffuser Dryer
  • Though compound does not pass directly between the silica gel beads within the diffusion dryer, it is possible that trace amounts of particles may contact the beads. The amount is negligible (around 2% particle loss at a flow rate of 5 LPM), but if this is a concern you can replace the beads between exposures. 
• Inflow Photometer adaptor
• Aerosol Bypass
• Tubing between Side Table and Elevation Platform
• Inhalation Tower Inner Core
• Inhalation Tower Port Adaptors
• Animal nose-cap and nose-seal

Other components may be exposed to aerosol but no flow that touches them can reach animals, so cross-contamination between subsequent exposures is impossible. 

Cleaning the Restraints/Chamber

Clean animal chamber of debris as needed by wiping with a cloth or rinsing with warm water. For a more thorough cleaning, use warm water and a mild dish detergent. It is best to let the chambers thoroughly air dry. Be certain that no water remains in any bias flow ports or tubing. If required, dry with a cloth towel.

• DO NOT submerge the chamber as this will affect pneumotach screens and the reference chamber.
• DO NOT USE WINDEX or window cleaner to clean the restrainer or plethysmograph. Continued use of Windex will eventually crack the lucite material.
• DO NOT put the chamber in the dishwasher.
• DO NOT use alcohol based cleansers.

Cleaning the Nebulizer Head

Clean the nebulizing equipment after each use. To clean the nebulizer head, remove it from the plethysmograph or aerosol block and rinse it in warm, soapy water. Let it soak for a few minutes. It can be submerged.

• DO NOT use a high-pressure water stream; let it run gently into the device.
• DO NOT touch the metal membrane or attempt to brush it, as this may cause damage, but do rinse it from both the top and the bottom
• DO NOT clean the head with alcohol. Alcohol will damage the metal membrane. It is best to use soapy water for all general cleaning.
• DO NOT leave the head attached to the chamber overnight after use.

If stubborn proteins build up on the head, dissolve an Efferdent tablet in a glass of water. Filter the solution with a syringe filter. Nebulize for 10 minutes. Rinse thoroughly, pat gently with paper towels, and air dry.

If you have been using a pathogen and wish to decontaminate, disconnect the head from the power cord and autoclave it using the “flash” steam sterilization cycle, 134C for 4 minutes.

Cautions

• To avoid mechanical or electrical damage, do not drop the nebulizer head or the control module.
• Do not use in the presence of devices generating high electromagnetic fields such as magnetic resonance imaging (MRI) equipment.
• Disconnect the nebulizer head from control module before cleaning.
• Do not immerse or autoclave the nebulizer control unit.
• Use only with components specified by Aerogen.
• Inspect all parts before use, and do not use if any parts are missing, cracked or damaged. In case of missing parts, malfunction or damage, contact your DSI representative.
• Do not use or store outside of specified environmental conditions.