Effective July 31, 2015

Standard Information
Standard Number:
UL 900
Standard Name:
Air Filter Units
Standard Edition and Issue Date:
7th Edition Dated September 2, 2004
Date of Revisions:
November 6, 2009 and February 14, 2012
Date of Previous Revisions to Standard:
7th Edition Dated November 28, 2007
Effective Date of New/Revised Requirements

Effective Date (see Schedule below): July 31, 2015

Impact, Overview, Fees and Action Required

Impact Statement:  A review of all Listing Reports is necessary to determine which products comply with new/revised requirements and which products will require re-evaluation. NOTE:  Effective immediately, this revised standard will be exclusively used for evaluation of new products unless the Applicant requests in writing that current requirements be used along with their understanding that their listings will be withdrawn on Effective Date noted above, unless the product is found to comply with new/revised requirements.

Overview of Changes: The November 6, 2009 update was administrative in nature (no impact to Certifications). The February 14, 2012 update was to add Clause 9.1.1. Specific details of new/revised requirements are found in table below.

Schedule:  So that shipping of products with Listing Marks will not be interrupted, an approximate schedule has been established to ensure Listing Reports are found compliant by Effective Date:

  • January 5, 2015 = 7-8 Month Report Review – Intertek will review all Reports. Update if compliance is verified or issue Findings Letter/Quote for any re-evaluations needed
  • February 6, 2015 = 6-5 Month Quote Cut-off – Quotes returned for necessary re-evaluations
  • July 1, 2015 = 30 Day Warning – Client advised of all non-compliant Reports to be Suspended
  • July 31, 2015 = Effective Date – ATM Suspended for all non-compliant Reports

Fees:  An initial review of Listing Report (s) will be covered by a direct billing project and will be invoiced at not more than $1000 per report.

Client Action Required:

Information – To assist our Engineer with review of your Listing Reports, please submit technical information in response to the new/revised paragraphs noted in the attached or explain why these new/revised requirements do not apply to your product (s).

Current Listings Not Active? – Please immediately identify any current Listing Reports or products that are no longer active and should be removed from our records. We will do this at no charge as long as Intertek is notified in writing prior to the review of your reports.

Description of New/Revised Technical Requirements

NOTE: Additions to existing requirements are underlined and deletions are shown lined out below.

  Revision: November 6, 2009
Entire StandardInfo

This update to the standard removes Class 1 and Class 2 References from the standard.

The UL 900 Standard has very good value for providing a level of safety between air filters that currently meet the class 2 level and air filters which cannot meet class 2, no matter if those filters are clean or dirty. However, the only measurable difference in a class 1 filter and a class 2 filter is when the filters are clean or before being used in service. Once the filters are put into service, the particle capture will change the flammability of the filters to where there is no longer any difference in a class 1 or a class 2 filter in the event of a fire. The concern is that the inclusion of a class 1 designation implies a level of protection that is not supported by any test data. Thus, the class designations in UL 900 do not offer any safety advantage or distinction between air filters and should be discontinued.

  Revision: February 14, 2012
9.1.1  New added Clause
With reference to 9.1, the marking shall be located on:
  1. the filter itself;
  2. the individual filter unit packaging;
  3. the packaging, for multiple filters distributed in one package;
  4. the media packaging; or
  5. the filter media roll core. 

CUSTOMERS PLEASE NOTE: This Table and column "Verdict" can be used in determining how your current or future production is or will be in compliance with new/revised requirements.

Contact Intertek