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Unique Part Numbers; Abbreviated Labeling Options for Cartridges and Filters

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Letter to All Respirator Manufacturers

Issue Date: April 22 , 2005

From: Heinz W. Ahlers, Acting Branch Chief, Respirator Branch, National Personal Protective Technology Laboratory

Subject: Unique Part Numbers; Abbreviated Labeling Options for Cartridges and Filters

NIOSH’s intention has always been that each respirator component will have a unique part number. However, NIOSH has discovered a few instances where this is not the case, and there have been requests from manufacturers to have more than one part number for a given component. In an effort to meet the needs of the manufacturers while still maintaining the concept of only one part number for field identification and traceability, NIOSH is offering options for replaceable cartridges and filters.

In instances where cartridge or filter protections do not vary based on the configuration and conditions of use, manufacturers must continue to follow the established part marking method which includes showing one unique part number on a cartridge or filter and listing the protections. NIOSH does allow one uniquely numbered part to be used in more than one approved configuration, for instance an approved filter may be used with more than one style of half facepiece .

In instances where the protections vary based on the configuration and conditions of use, the manufacturer must continue to list only one unique part number on a cartridge or filter. However, two options for labeling the additional protections are available:

  • Option A (present): As is presently done, the manufacturer may continue to carry dual inventory. The manufacturer may place one label and part number on a cartridge or filter showing one set of protections. For respirator configurations that have different or additional protections, the manufacturer must place a different label and part number on the cartridge or filter such that, to the user, this physically identical cartridge or filter appears as two different components.
  • Option B (new): To avoid dual inventory, manufacturers may choose to list only the protections that apply to all approved configurations. In addition, the label may state: "Also NIOSH approved for <additional protection> but ONLY when used with <additional configuration>.” An example would be: "OV/CL/SD/P100. Also NIOSH approved for CS/CN but ONLY when used with an approved Full Facepiece." With option B, the manufacturer must also add to the approval label a new caution "LL" which states: "LL- This respirator contains filter or cartridge components that are not approved for all protections in all configurations. Check the specific row on the NIOSH approval label to ensure proper use.”

As a final point of clarification, this policy applies only to cartridges and filters. All other components must continue to have one unique part number per component.

NIOSH will now accept from approval holders Extension of Approval applications to change any component that is currently being produced and marked with multiple part numbers to a unique part number. NIOSH expects all such applications to be submitted no later than one year from the date of this letter. Manufacturers will be permitted to deplete any existing stock, and must notify NIOSH of this anticipated date in the application.

For questions on this issue, please call the NIOSH Certification group at 412-386-4000.

Unique Part Numbers; Abbreviated Labeling Options for Cartridges and Filters [PDF - 45 KB]