Pass-throughs and air showers keep contamination at bay

by Laureen Belleville

Click here to enlarge image

In any application where contamination is critically important—such as life science, biomedical, pharmaceutical, parenteral drug, microelectronics, aerospace and precision manufacturing—pass-throughs and air showers are considered essential equipment.

RIGHT. Pass-throughs and air showers keep particle contamination from entering the cleanroom.

Normally there is no activity in a pass-through. Simply put, it is a box through which product is passed in and out of a cleanroom. Models are available in a variety of sizes, from small wall-mounted to large floor-mounted cart/wagon pass-throughs. When comparing products, be aware that some manufacturers quote inside dimensions, while others quote outside dimensions. Options include stainless steel shelves, fluorescent lights and a talk-through installed in the doors.

Click here to enlarge image

Air showers, on the other hand, are intended for personnel or material and they utilize clean air to remove particle contamination from people and things entering the cleanroom. For example, one manufacturer's product accomplishes this by supplying ISO Class 5 (Class 100) air at a high velocity through strategically distributed nozzles that bathe an individual as he stands in or walks through the chamber. Contaminated air is then drawn out through hollow wall returns and a HEPA filter. Sometimes, pass-throughs may incorporate air showers.

Click here to enlarge image

Both, however, incorporate either mechanical or electrical interlocking doors that prevent cleanroom air from escaping and contaminated air from entering the cleanroom. Only one door can be opened at a time, which further guarantees the integrity of the cleanroom.

Click here to enlarge image

Manufacturers offer products constructed from various materials, from plastics to stainless steel, to meet requirements for cleanliness, durability, static-dissipation, chemical resistance and fire safety. While the choice is up to the user, the application and engineering specifications dictate which product is best. For example, pharmaceutical and biomedical applications generally require the use of a stainless steel product, while plastics often can suffice for electronics applications. For some, price is also a determining factor: the stainless steel version costs significantly more than its plastic counterpart.

Distributors

The following companies distribute pass-throughs and air showers for cleanroom applications:

  • Terra Universal; Anaheim, CA; Ph: (888) 777-3363; Fax: (714) 992-2179; www.terrauni.com
  • Ultrapure Technology; Ph: (770) 932-0309; Fax: (770) 932-0809; www.ultrapuretechnology.com
  • VWR Scientific; West Chester, PA; Ph: (610) 424-2858; Fax: (610) 918-8310; www.vwrsp.com

This article was prepared with assistance from Kevin Leak, vice president, Jeff Rhoades, marketing manager, and Eliena Tipler, marketing manager, at VWR Scientific Products in West Chester, PA.

POST A COMMENT

Easily post a comment below using your Linkedin, Twitter, Google or Facebook account. Comments won't automatically be posted to your social media accounts unless you select to share.