What are the requirements of the Telcordia NEBS standards pertaining to air filters?Sunday, March 11th, 2012
R4-18  All fan-cooled equipment shall be equipped with filters. Fan filters shall be replaceable with equipment operating. Rectifiers, distribution bays, and sealed equipment with only outside fan cooling do not require filters.
R4-19  All equipment fan filters used in equipment occupying over 2U of vertical rack space (90 mm or 3.5 in) shall have either a:
|Minimum dust arrestance of 80%, per ASHRAE Standard 52.1-1992,Gravimetric and Dust-Spot Procedures for Testing Air Cleaning Devices Used in General Ventilation for Removing Particulate Matter, or|
|Minimum Efficiency Rating Value (MERV) of 4, per ANSI/ASHRAE Standard 52.2-2007, Method of Testing General Ventilation Air Cleaning Devices for Removal Efficiency by Particle Size|
R4-20  All equipment fan filters used in equipment occupying 2U of vertical rack space (90 mm or 3.5 in) or less shall have either a:
|Minimum dust arrestance of 65%, per ASHRAE Standard 52.1-1992, or|
|Minimum Efficiency Rating Value (MERV) of 2, per ANSI/ASHRAE Standard 52.2-2207,|
R4-21 Fan filters shall meet the minimum fire rating of Underwriters Laboratories, UL 900-2004, Standard for Air Filter Units, plus revisions, and be marked “UL Classified”..
NOTE: Polymer filter media must also meet the fire-resistance requirements per Section 184.108.40.206, “Material/Components Fire-Resistance Criteria.
R4-22  Construction and system fit of equipment fan filters shall prevent any air bypass. Inadvertent leakage that may result from mechanical fits or tolerances, (examples may include spaces between circuit pack face plates, connector or cable matrices, chassis screw or mounting holes, etc.), is not considered bypass.
R4-23 Equipment shall have provision for fan-filter replacement with particulate contaminants from the filter being introduced into equipment. If filters can be changed with fans operating, filter replacement methods that minimize touching the media and/or dislodging captured particulates shall be specified. Filter designs with rigid frames that are withdrawn from the airflow for removal satisfy the intent of this requirement.
R4-24  The equipment manufacturer shall provide a method for determining equipment fan filter replacement schedules.
O4-25  If possible, active alarming should be provided to indicate the need for fan filter replacement.
R4-26  Equipment fan filters shall be single use and not the types the require cleaning.
O4-27  It is an objective that equipment fan filters utilize recyclable materials.
R4-61  Foamed polymers shall meet the HF-1 requirements of ANSI/UL 94-1996.
NOTE: Foamed polymer air filter assemblies must also meet the fire-spread requirements of GR-63-CORE, Section 220.127.116.11, “Equipment Fan-Filter Criteria.”
R8-3  All fan-cooled equipment shall be configured with filters.
R8-4  All equipment fan filters shall have a minimum dust arrestance of 80%. This represents a low efficiency 10 to 15% American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) dust spot rating.
R8-5  Fan filters shall have a minimum fire rating of Underwriters Laboratories (UL) Class 2.