NATIONAL BUREAU OF STANDARDS REPORT

PERFORMANCE TEST OF FARR TYPE 83 MEDIA

WITH THE '’ROLL KLEEN" AUTOMATIC RENEWABLE MEDIA AIR FILTER

Carl W. Coblent z and Paul R. Achenbach

Report to.

General Services Administration

Public Buildings Service

Washington 25* D, C 0

7530

manufactured by

Farr Company

Los' Angeles, California

by

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS
THE NATIONAL BUREAU OF STANDARDS

FuncUoms and Activities

The functions of the National Bureau of Standards are set forth in the Act of Congress, March 3, 1901, as amended by Congress in Public Law 619, 1950. These include the development and maintenance of the national standards of measurement and the provision of means and methods for making measurements consistent

with these standards; the determination of physical constants and properties of materials; the development of methods and instruments for testing materials,* devices, and structures; advisory services to government agencies on scientific and technical problems; invention and development of devices to serve special needs of the Government; and the development of standard practices, codes, and specifications. The work includes basic

and applied research, development, engineering, instrumentation, testing, evaluation, calibration services,

and various consultation and information services. Research projects are also performed for other government

agencies when the work relates to and supplements the basic program of the Bureau or when the Bureau’s

unique competence is required. The scope of activities is suggested by the listing of divisions and sections on the inside of the back cover.

Publications

The results of the Bureau's research are published either in the Bureau’s own series of publications or

in the journals of professional and scientific societies. The Bureau itself publishes three periodicals avail- able from the Government Printing Office: The Journal of Research, published in four separate sections,

presents complete scientific and technical papers; the Technical News Bulletin presents summary and pre- liminary reports on work in progress; and Basic Radio Propagation Predictions provides data for determining

the best frequencies to use for radio communications throughout the world. There are also five series of nonperiodical publications: Monographs, Applied Mathematics Series, Handbooks, Miscellaneous Publications,

and Technical Notes. A complete listing of the Bureau’s publications can be found in National Bureau of Standards Circular

460, Publications of the National Bureau of Standards, 1901 to June 1947 ($1.25), and the Supplement to National Bureau of Standards Circular 460, July 1947 to June 1957 ($1.50), and Miscellaneous Publication 240,

July 1957 to June 1960 (Includes Titles of Papers Published in Outside Journals 1950 to 1959) ($2.25); avail- able from the Superintendent of Documents,' Government Printing Office, Washington 25, D. C.
NATIONAL BUREAU OF STANDARDS REPORT

PSiOJECT NBS REPORT

1003-30-10630 July 20, 1962 7530

PERFORMANCE TEST OP FARR TYPE 83 MEDIA

WITH THE '’ROLL KLEEN" AUTOMATIC RENEWABLE MEDIA AIR FILTER

manufactured by

• Farr Company

Los Angeles, California

by

Carl W. Coblent z and Paul R. Achenbach

Mechanical Systems Section

Building Research Division

to

General Services Administration

Public Buildings Service

Washington 25* D. C.

IMPORTANT NOTICE

NATIONAL BUREAU OF S

Intended for use within the to additional evaluation and

listing of this Report, eithei the Office of the Director, f however, by the Governtnen

to reproduce additional cop

a , ,, ... , progress accounting documents Approved for public release by the jrmally published it is subjected

Director of the National Institute of >• reproduction, or open-literature

Standards and Technology (NIST)

on October 9, 2015. I prepared if that agency wishes

<J0s>

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

PERFORMANCE TEST OF FARR TYPE 83 MEDIA

WITH THE ” ROLL KLEEN" AUTOMATIC RENEWABLE MEDIA AIR FILTER

manufactured by

Farr Company

Los Angeles, California

Carl W. Coblentz and Paul R. Achenbach

1. Introduction

At the request of the Public Buildings Service, General

Services Administration, the performance characteristics of the

Farr type 83 media was determined on a "Roll-Kleen" automatic

renewable media type air filter. The scope of this examination

included the determination of the dust-holding capacity and the

arrestanoes of Cottrell precipitate and of the particulate

matter in the laboratory air when the face velocity was maintained at 500 ft/min and the pressure drop across the media did

not exceed 0.5 in. W.G.

2. Description of Test Specimen

The filter media was supplied by the Farr Company of Los

Angeles, California, and was Identified as their Roll-KleenType 83 Media. The roll of media was 3 feet wide and approximately 65 feet long and the media expanded to a thickness of

about 2 inches when unrolled. The mat was made of ^glass fibers,

bonded with an organic binder and was reinforced on the downstream side by a rigid scrim that was secured to the mat by the

bonding material. The mat was treated with a viscous adhesive,

said to be tricresyl phosphate. The weight of the mat was

approximately 35 grams per square foot and a microscopic examination of the glass fibers indicated that most were between 30

and 50 microns in diameter and several inches long.

The filter mat was installed in a Roll-Kleen filter frame,

model 3-70, which had been modified for use with the National

Bureau of Standards air filter test apparatus. The modification

of the apparatus consisted principally of a metal enclosure

which covered the spool of clean material at the top as well as

the loaded spool at the bottom. The inlet and outlet openings

In the filter apparatus were 24-inch square to match the size

of the test duct, and two flanges permitted the connection of

the device to the two sections of the air filter test duct. The

advance of the filter mat was controlled by a pressure switch

which operated an electric motor, connected to the lower spool.

The pressure switch had an adjustable range, but a fixed differential of approximately 0.08 in. W.G.
2

3 . Test Method and Procedure

The filter media was tested at the rated face velocity of

500 ft/min. The arrestance determinations were made in accordance with the NBS Dust Spot Method described in a paper by R.S.

Dill entitled "A Test Method for Air Filters” (ASHVE' Transactions*

‘Voll. 44* p. 379^ 1938). The filter under test was installed in

the test apparatus and carefully sealed to prevent any by-pass of

air or inward air flow into the test apparatus* except through the

measuring' orifice. After establishing the correct air flow rate

through the filter* samples of air were drawn from the center

points of the test duct 2 feet upstream and 8 feet downstream of

the test specimen at equal rates and passed through known areas

of Whatman No. 4l filter paper. Arrestance determinations were

made periodically with the particulate matter in the laboratory

air as the aerosol and also with Cottrell precipitate injected

into the air stream at a ratio of 1 gram per 1*000 cu ft of air.

The light transmission of the sampling papers was measured

on the same area of each paper before and after the test and the

two sampling papers used for any one arrestance determination

were selected to have the same light transmission when clean.

For determining the arrestance of the particulate matter

.in the laboratory air* equal sampling areas were used in the

upstream and downstream samplers. A similar increase of the

opacity of the two sampling papers was obtained by passing the

sampling air through the upstream paper only part of the time

while operating the downstream sampler continuously. This was

accomplished by installing one solenoid valve in the upstream

sampling line and another one in a line by-passing* the sampler.

The solenoid valves were operated by an electric timer and a relay so that one was open while the other one was closed during any desired percentage of the 5-minute timer cycle* reversing the position of the two valves during the remainder of the

cycle. The arrestance* A (in percent)* was then determined with

the formula;

A = 100 - T x

AU

where T is the percentage of time during which air was drawn

through the upstream sampler* and AU and AD are the observed

changes in the opacity of the upstream and downstream sampling

papers, respectively.

For determining the arrestance of the filter with Cottrell

precipitate as the test dust* different size areas of sampling

paper were used upstream and downstream of the filter in order

to obtain a similar increase of opacity on both sampling papers.
- 3

-

The arrestance was then calculated by the formula;

A = (1 ' x w)x 100

where the symbols A, AU, and AD are the same as Indicated above

D

are the upstream and downstream sampling areas,

« Arrestance determinations were made with Cottrell precipitate when .the media was clean, at intervals thereafter during

the loading of the initially-exposed section of media, and

several times after incremental advance of the media began. The

media was loaded with cotton linters and Cottrell precipitate

in the ratio of 4 to 96 parts by weight. When an arrestance

determination was made with Cottrell precipitate, the linters

were not added, but this interruption in linter addition was

compensated for later to maintain the selected ratio of the two

contaminants. The Cottrell precipitate had been previously

sifted through a 100-mesh screen and the lint was prepared by

grinding No. 7 cotton linters through a Wiley mill with a 4-

millimeter screen.

The pressure drop across the filter media under test was

observed and recorded after each arrestance determination, and

after introduction of each 20-gram increment of Cottrell precipitate into the test duct.

The advance of the filter media was observed through a window in the test apparatus by determining the position of a marker, attached to the mat, relative to a yardstick mounted in

the filter housein, adjacent to the mat. A pilot light connected

in parallel with the electric motor enabled the operator to

record the pressure drop across the medium at the beginning and

at the end of each advance cycle. The pressure switch was

adjusted to commence the advance cycle when the pressure drop

reached 0.500 in. W.G. or a slightly lower value.

4 . Test Results

The test results are summarized in Tables 1 and 2. Table 1

shows the arrestance of the media at different pressure drop

values for both the particulate matter in the laboratory air

and Cottrell precipitate as the initial section of media was

being loaded before the first advance and. immediately after the

first advance of the media. The pressure drop of the clean

medium was 0.160 in. W.G. The arrestance of the clean media

for the particulate matter in the laboratory air was 7 percent

and for Cottrell precipitate was 70 percent. The arrestance of

the mat increased as the dust load increased and ranged from 8l

percent to 86 percent for Cottrell precipitate at pressure drop

values between 0.4 and 0.5 in. W.G. Two arrestance determinations with the particulate matter in the laboratory air at a

and Sy and S

respectively
- 4 -

pressure drop above 0.4 in. W.G. showed 21 percent and 19 percent,

respectively.

Table 2 shows the mat travel, the dust load, and the pressure

drop across the filter immediately before and after each advance

of the media. It will be noted that the incremental 1 advance was

between 2 in. and 3 1/2 in., averaging 2 5/8 in. The pressure

drop at the beginning of the advance cycle ranged from 0.500 in.

W.G. to 0.468 In. W.G .

3

averaging 0.486 In. W.G. and the pressure

drop at the end of the advance cycle ranged from 0.425 In. W.G.

to 0.390 in. W.G., averaging 0.406 in. W.G. The average differential was 0.080 in. W.G.

The dust loads shown in Table 2 are the cumulative weights

per foot width of Cottrell precipitate and lint that had been

introduced into the test duct at the beginning of each advance

cycle.

The dust load per unit area of filter medium provides a relative measure of the rate of consumption of mat material

during actual use. The dust load per unit area at steady state

operation has been defined as the "Dust-Holding Capacity. This

value has been obtained by plotting the cumulative advance values

against the cumulative dust load after the medium had advanced a number of times. The mat travel was plotted against the dust

load in Figure 1 and a straight line was drawn that best fitted

the individual points of observation,, Disregarding the insignificant mass of particulate matter collected on the media during

the arrestance determinations with laboratory air, . the slope of

this line expresses the dust-holding capacity of the medium.

AccoTding to the graph, while the mat advanced 15 inches, from

the 35~inch position to the 50-inch position, the cumulative

dust load increased from 638 g/ft width to 8§3 g/ft width, or

by 255 g/ft width. The dust-holding capacity was therefore;

255 x = 204 g/'sq ft

The test results obtained with the Roll Kleen Type 83 media

at a face velocity of 500 ft/min, are summarized below;

.*•0.160 in. W.G.

0.486 to 0.406 In. W.G.

; 7 percent

70 percent

20 percent

83 percent

204 g/sq ft.

1 . Pressure drop of clean mat

2. Average operating pressure

3« Arrestance of clean mat;

Particulate matter in laboratory air

Cottrell precipitate

4. Average arrestance at steady states

Particulate matter In laboratory air

Cottrell precipitate

5. Dust-Holding Capacity

USCOMM-NBS-DC
TABLE 1

Arrestance and Pressure Drop

at the start of the loading process

FARR ’’ROLL KLEEN” TYPE 83 MEDIA

Pressure Drop

in. W.G.

Arrestance

percent

0.160 7

0.163 70

0.165 69

0.170 69

0.308 71

0.425 81

0.428 81

0.475 84

0.500 85

0.430 21

0.438 83

0.479

0.483

19

86

^Aerosol A - Particulate matter in laboratory air

C - Cottrell Precipitate in laboratory air

Aerosol*

<00000000<0<0



U. S. DEPARTMENT OF COMMERCE

Luther H. Hodges, Secretary

NATIONAL BUREAU OF STANDARDS

A. V. Astin, Director THE NATIONAL BUREAU OF STANDARDS

The scope of activities of the National Bureau of Standards at its major laboratories in Washington, D.C., and

Boulder, Colorado, is suggested in the following listing of the divisions and sections engaged in technical work.

In general, each section carries out specialized research, development, and engineering in the field indicated by

its title. A brief description of the activities, and of the resultant publications, appears on the inside of the

front cover. WASHINGTON, D. C.

Electricity. Resistance and Reactance. Electrochemistry. Electrical Instruments. Magnetic Measurements

Dielectrics. High Voltage.

Metrology. Photometry and Colorimetry. Refractometry. Photographic Research. Length. Engineering Metrology.

Mass and Scale. Volumetry and Densimetry.

Heat. Temperature Physics. Heat Measurements. Cryogenic Physics. Equation of State. Statistical Physics.

Radiation Physics. X-ray. Radioactivity. Radiation Theory. High Energy Radiation. Radiological Equipment.

Nucleonic Instrumentation. Neutron Physics.

Analytical and Inorganic Chemistry. Pine Substances. Spectrochemistry. Solution Chemistry. Standard Refer- ence Materials. Applied Analytical Research. Crystal Chemistry.

Mechanics. Sound. Pressure and Vacuum. Fluid Mechanics. Engineering Mechanics. Rheology. Combustion

Controls. Polymers. Macromolecules: Synthesis and Structure. Polymer Chemistry. Polymer Physics. Polymer Characterization. Polymer Evaluation and Testing. Applied Polymer Standards and Research. Dental Research.

Metallurgy. Engineering Metallurgy. Microscopy and Diffraction. Metal Reactions. Metal Physics. Electrolysis

and Metal Deposition.

Inorganic Solids. Engineering Ceramics. Glass. Solid State Chemistry. Crystal Growth. Physical Properties.

Crystallography.

Building Research. Structural Engineering. Fire Research. Mechanical Systems. Organic Building Materials. Codes and Safety Standards. Heat Transfer. Inorganic Building Materials. Metallic Building Materials. Applied Mathematics. Numerical Analysis. Computation. Statistical Engineering. Mathematical Physics. Operations Research. Data Recessing Systems. Components and Techniques. Computer Technology. Measurements Automation.

Engineering Applications. Systems Analysis.

Atomic Physics. Spectroscopy. Infrared Spectroscopy. Solid State Physics. Electron Physics. Atomic Physics.

Instrumentation, Engineering Electronics. Electron Devices. Electronic Instrumentation. Mechanical Instru- ments. Basic Instrumentation. Physical Chemistry. Thermochemistry. Surface Chemistry. Organic Chemistry. Molecular Spectroscopy. Molecular Kinetics. Mass Spectrometry.

Office of Weights and Measures. BOULDER, COLO.

Cryogenic Engineering Laboratory. Cryogenic Equipment. Cryogenic Processes. Properties of Materials. Cryogenic Technical Services. CENTRAL RADIO PROPAGATION LABORATORY

Ionosphere Research and Propagation. Low Frequency and Very Low Frequency Research. Ionosphere Research. Prediction Services. Sun-Earth Relationships. Field Engineering. Radio Warning Services. Vertical Soundings Research.

Radio Propagation Engineering. Data Reduction Instrumentation. Radio Noise. Tropospheric Measurements.

Tropospheric Analysis. Propagation-Terrain Effects. Radio-Meteorology. Lower Atmosphere Physics.

Radio Systems. Applied Electromagnetic Theory. High Frequency and Very High Frequency Research. Modulalation Research. Antenna Researcn. Navigation Systems.

Upper Atmosphere and Space Physics. Upper Atmosphere and Plasma Physics. Ionosphere and Exosphere Scatter. Airglow and Aurora. Ionospheric Radio Astronomy.

RADIO STANDARDS LABORATORY

Radio Physics. Radio Broadcast Service. Radio and Microwave Materials. Atomic Frequency and Time-Interval

Standards. Millimeter-Wave Research.

Circuit Standards. High Frequency Electrical Standards. Microwave Circuit Standards. Electronic Calibration Center.