NBSIR 75-965

AN EVALUATION AND ASSESSMENT

OF EXISTING DATA AND PROCEDURES

FOR THE MEASUREMENT OF NOISE

FROM DOZERS AND LOADERS

Applied Acoustics Section

Institute for Basic Standards

National Bureau of Standards

Washington, D. C. 20234

October 1975

Final Report

Prepared for U.S. Environmental Protection Agency

Washington, D. C. 20460

U.S. DEPARTMENT OF COMMERCE, Rogers C.B. Morton, Secretary

James A. Baker, III, Under Secretary

Dr. Betsy Ancker-Johnson, Assistant Secretary for Science arid Technology

NATIONAL BUREAU OF STANDARDS, Ernest Ambler. Acting Director

Table of Contents

Page

1. Introduction and Scope 1

2. Dozer and Loader Description and Design 1

2.1. Classification and Identification 1

2.2. Categorization of Equipment 3

2.3. Industry Structure 3

2.4. Design Characteristics 5

3. Effects of Noise and Parties Affected 9

4. Major Noise Sources 9

4.1. Engine Related Noise Sources 9

4.2. Other Noise Sources 11

5. Typical Work Cycles 11

6. Existing Measurement Procedures 12

7. Data Base and Correlations 17

8. Overview of Dozer and Loader Noise Measurement Difficulties. . . 17

8.1. Probable or Potential Measurement Difficulties 17

8.1. a. Representative Noise Regulations 18

8.2. Classification 18

8.3. Machines to be Tested

.

18

8.4. Test Site 19

8.5. Quantity Measured 20

8.6. Acoustic Environment 21

8. 6. a. Constructive and Destructive Interference

Effects 22

8.6.b. Heat Radiation 22

8.6.C Cooling Fan Wind Generation 22

8.7. Instrumentation 22

8.8. Current Versus Alternative Test Procedures 23

8. 8. a. Current Test Procedures 23

8.8.b. Alternative Test Procedures 25

9. Appendix A. Existing Dozer and Loader Noise Measurement

Procedures 27

10. References 38

i
Executive Summary

EPA is charged with taking strong comprehensive action to protect

public health and welfare from increasing noise. Accordingly, the Agency

initially identified medium and heavy trucks and portable air compressors as major noise sources and promulgated noise emission regulations covering

these products. Additional products have recently been identified as major

noise sources, including wheeled and tracked dozers and loaders. For the

purposes of this report, dozers and loaders can be defined as any

construction or industrial product which performs the dozing (pushing or pulling) operation and any construction or industrial machine which has a front end loading bucket, respectively.

As was the case for medium and heavy trucks, the dozer and loader noise

of interest can be categorized mainly as the noise produced by the tractor

power plant. For dozers and loaders, this includes noise from the cooling

fan, engine, exhaust and intake. Other noises of interest arise from drive

train systems, hydraulic components and relief valves, and, in the case of

tracked vehicles, the track itself. The noise from the power plant

increases as the engine speed (and power) increases. Maximum power plant

noise usually occurs when the engine is delivering maximum power at its

maximum operating speed. The percentage of time a dozer or loader spends at

maximum noise conditions depends upon the work cycle, i.e., the material

being moved, the distance that the material is being moved, and to some

extent, the manner in which the dozer or loader is operated.

This report reviews existing noise measurement procedures which can be

applied to dozers and loaders with regard to their usefulness in the regulation of dozer and loader noise as well as the availability, extent and

applicability or' existing data. On the basis of this review, the following

probable or potential measurement difficulties have been identified that

could hinder the promulgation and/or enforcement of future EPA regulations

to control the noise emissions from dozers and loaders.

A NEED TO IDENTIFY AND CLASSIFY CONSTRUCTION EQUIPMENT COVERED . When

mandatory regulations are applied, industry and EPA must precisely

decide which equipment is covered by the regulation and which is not.

Exact definitions specifying which equipment is to be classified as a dozer or loader must be prepared. This may include equipment labeled

by the manufacturer as either industrial equipment or construction

equipment. Categorization of equipment according to horsepower, size,

or other parameters also must be accomplished.

A NEED TO SPECIFY THE DEGREE OF ASSEMBLAGE OF THE MACHINE TO BE TESTED . Many machines are not fully assembled at the main manufacturing

facility. Some of these machines are shipped to the dealer or other

facility where attachments such as dozer blades or loader buckets,

etc., are installed on the base machine. It may not be practical to

require testing on the fully completed machine (including attachments).

ii
It is highly probable that testing could be performed on the base

machine without attachments and meaningful results obtained; however,

data are necessary to support this assumption. The degree of

assemblage of the base machine required for testing must be specified.

A NEED TO ACCOUNT FOR HEAT RADIATION FROM THE ENGINE . Under certain

conditions heat radiation from the engine compartment can cause measurement problems during stationary tests. Hot air surrounding the

equipment can cause measurement inconsistencies due to changes in the

noise generation mechanisms and noise radiation to the surrounding

environment. This phenomena should be investigated.

A NEED TO ACCOUNT FOR ENVIRONMENTAL/ SITE EFFECTS . There is a need for

the various environmental and test site effects on noise generation,

radiation and/or propagation to be systematically investigated and

correction factors developed so that measurements made under any

conditions may be corrected to a single standard set of conditions. If

correction factors are not feasible then there is a need for a site

calibration procedure or definition of limiting test conditions.

A NEED FOR SIMPLER TEST PROCEDURE . There exists a need to develop a test procedure that is simpler to perform than those specified in

current standards and is less dependent on weather and test site

variables. Correlation should be established between the results

obtained utilizing such a test and human response to dozer and loader

noise

.

A NEED TO BETTER SPECIFY TRANSIENT RESPONSE OF INSTRUMENTATION . There

exists a need to evaluate the response of existing instrumentation to

actual transient signals, e.g., as would occur in a typical work cycle,

in order to establish the relationships among the various precision

instruments, to supply data to strengthen existing standards, and to

establish a data base so that the technical community, manufacturers,

lawmakers and enforcement agencies will have a common basis for

comparison of results obtained using supposedly comparable equipment.

AN ALMOST NON-EXISTENT DATA BASE . Very limited data exist in the

public domain on the noise levels associated with dozer and loader

operations. Data which do exist are proprietary in nature and were gathered mainly as engineering tools to facilitate the development of

product lines by the manufacturer.

A LACK OF TYPICAL USAGE DATA. In order to develop an appropriate,

reliable and repeatable test procedure, it is necessary to consider the

range of possible dozer and loader operational modes and the noise

emission associated with each mode. What is needed is definition of

the percentage of time which a dozer or loader typically spends at

different operational modes during a work cycle. Such data could serve

as the basis for logical decisions on whether a multi-modal test

procedure or simply a few selected modes of operation should be

iii
specified as part of the test procedure. Such typical usage data do

not presently exist for dozers and loaders.

In summary, it is doubtful that the data in the open literature are extensive enough to provide EPA with the information needed for a comprehensive analysis of the economic costs and technical feasibility associated

with a given regulation. Furthermore, there are practically no data available upon which to base an evaluation of alternative dozer and loader noise

measurement procedures or to establish correlations between the noise

associated with various operational modes and the noise measured utilizing

various test procedures.

Thus, it appears that EPA will have to generate a rather extensive

physical data base and investigate alternative measurement procedures prior

to formulation of the Notice of Proposed Rule Making.

iv
An Evaluation and Assessment of Existing Data and Procedures

for the Measurement of Noise From Dozers and Loaders

This report reviews (1) existing construction equipment noise

measurement procedures with regard to their usefulness in the regulation of

noise from dozers and loaders and (2) the availability, extent and

applicability of existing data. On the basis of this review, probable or potential measurement-related difficulties are identified that could hinder

the promulgation and/or enforcement of future EPA regulations to control the

noise emission from dozers and loaders.

Key Words: Acoustics (sound); dozer; loader; measurement methodology;

noise emission standard; noise measurement.

1. Introduction and Scope

The National Bureau of Standards (NBS) , under the sponsorship of the

Office of Noise Abatement and Control (ONAC), U. S. Environmental Protection

Agency, has attempted to identify probable or potential measurement

difficulties that could hinder the promulgation and/or enforcement of future

noise regulations to control the noise emissions from dozers and loaders. A

search of the open literature in conjunction with numerous industrial and

private sector contacts established the basis for discussion of:

1. The basic characteristics of dozer and loader design and

construction.

2. The effect of dozer and loader noise and the parties affected.

3. The major component noise sources for dozers and loaders.

4. The normal or typical modes of operation characteristic of dozers

and loaders.

5. The usefulness of existing measurement procedures for use in

regulation of the noise from dozers and loaders, considering the

viewpoint of EPA, manufacturers and enforcement personnel.

6. The availability, extent and applicability of existing data that

could be utilized by EPA in their efforts to promulgate noise

emission regulations for dozers and loaders.

This report is limited to those factors related to the measurement of

dozer and loader noise. EPA/ONAC will independently investigate the technical feasibility and economic implications of dozer and loader noise

regulation.

2. Dozer and Loader Description and Design

2.1. Classification and Identification

Classification and identification of construction equipment is very
complicated. Classifications which now exist are broad in nature, include

both small and large equipment, and do not properly identify the equipment

being classified. Agreement must be reached by EPA and industry as to how

equipment is to be classified.

What is a dozer, for instance? EPA views a dozer as a product which

performs the^dozing (pushing or pulling) operation. In reports by

Patterson[l]— and A. T. Kearney, Inc. [2], the term "traction vehicle" is

coined to signify "any engine powered tractor used to push or pull loads at

construction sites." Industry does not recognize the term "traction

vehicle", and a "dozer" is not viewed as being the end product vehicle. A

dozer is simply a major component or attachment to a crawler (tracked) or wheeled tractor which performs the dozing operation. The industry viewpoint

is based on the fact that some 20% of all crawler or wheeled tractors

perform other pushing or pulling operations which never require a dozer

attachment and thus are not equipped with one. SAE[3] defines a tractor as "a self-propelled machine used to exert a push or pull force through a mounted attachment or drawbar to move objects or material. Tractors include

both crawler tractors and wheel tractors." Another SAE standard[4] refers

to a dozer as being the blade attachment only.

Loaders, as viewed by EPA, include tractors with front loading attachments as well as machines with integrally mounted front loading buckets.

According to SAE[3], a loader is "a self-propelled machine with an integral

front-mounted bucket supporting structure and linkage that loads material

into the bucket through forward motion of the machine and lifts, transports,

and discharges material. Not included are tractors with front-end loader

attachments." Other SAE standards[5,6] which describe nomenclature and

definitions of front end loaders only describe components and define the

operations which pertain to the bucket and its supporting mechanisms.

In different geographic locations, different names are used for the same equipment. For instance, a loader is called a "high lift" in

Wisconsin, yet may be called a "power shovel" in other areas. Many loaders

also are equipped with backhoe attachments and are then referred to as "excavators"

.

There are literally thousands of categories and combinations which may

exist. A base machine — a tractor — is built and certain attachments are

added. Some attachments are installed at the dealer's facility, some are added by the purchaser. Some attachments, though specifically designed for

a particular machine and approved for use by the base machine manufacturer,

are made by specialty manufacturers. Frequently the application of a particular base machine is not even known when it is manufactured or sold.

When mandatory regulations are applied, it must be clear precisely

which equipment is covered by the regulation and which is not. Classifications should not only identify the equipment but should categorize

—^Numbers in brackets indicate the literature references at the end of

this report.

2
equipment according to horsepower, use, or other parameters.

For the purposes of this report, the viewpoint of EPA will be followed

when describing dozers or loaders. A dozer is the product which performs

the dozing (pushing or pulling) operation. A loader is any machine with a front end loading bucket whether integrally mounted or installed as an attachment.

2.2. Categorization of Equipment

Equipment is sometimes categorized as either "industrial" or "construction". The definition between the two categories is obscure even

to the equipment manufacturers, the choice of category being primarily a marketing decision. In general, industrial equipment is lightweight and is more utilitarian in nature than construction equipment. Some industrial

equipment is essentially farm tractors to which attachments can be added.

This equipment, in addition to being used on farms, might be used by

homebuilders , utility companies, or landscapers to pick up or push loose

material, or do rough grading and other light work. Most industrial plants

would have some equipment of this size available to do a variety of jobs.

Small tracked vehicles of approximately 60 hp or under might also be

included in this category.

Construction equipment can run the gamut in size from 20 hp machines up

to 2000 hp or more. Differences in acoustic spectral characteristics may

exist depending on the horsepower and size of the machine due to different

noise sources being predominant.

2.3. Industry Structure

An extensive survey of current data on the dozer and loader population

in the United States and recent year dozer and loader sales information was

not made. Data compiled in 1974 by A. T. Kearney, Inc. [2] for "traction

vehicles" is repor.ted to give an indication of the industry structure. The

data reported are for vehicles commonly referred to as crawler or wheeled

dozers.

Manufacturers of "traction vehicles" obtain raw materials and

components used in the manufacturing process from interdivisional transfers,

component suppliers and raw material suppliers. Construction equipment

dealers are the primary channel of distribution either through sale or lease

to the primary end user. Estimated percentages of units shipped to the

primary end users for the period 1968-1972 are given in Table 1.

The method of distribution is predominantly by independent authorized

dealers with some factory branches and factory owned dealerships. Units can also be distributed direct to the end user. Approximately 30% of "traction

vehicles" are obtained through rental or rental/purchase agreements.

Manufacturers in the construction industry are basically large and

3
Table 1

Estimated percentage range of total traction vehicle unit

shipments by end use market, 1968-1972[2]

.

End Use Market Percentage of Units Shipped

(Range)

Construction Industry 52 -- 57$

Forestry Industry 13 -• 19

Mining Industry h -- 8

Industrial Users 5

-- 10

Government Agencies 10 -- 15

Other Users 1 - 6

Total 100$

Table 2

Estimated sales of divisions or subsidiaries whose product

lines include manufacture of traction vehicles [2].

Manufacturer Estimated Sales

($ Millions)

Allis-Chalmers* $ 198.0

J. I. Case 1+26.9

Caterpillar Tractor 2,537.2

Clark Equipment 296.1

Deere & Company 306.2

International Harvester kll.9

Komatsu Manufacturing Company 13.0

Massey-Ferguson, Incorporated 172.2

M-R-S Manufacturing Company 5.0

V-Con Division of Marion Power Shovel .8

Terex (Division of General Motors) N/A

*Allis-Chalmers has divested their interests in construction

equipment - now known as Fiat-Allis.

4
diversified. They generally produce other product lines such as farm,

industrial or transportation equipment. There are relatively few

manufacturers of construction equipment due to the capitol intensive nature

of the industry.

"Traction vehicles" are manufactured by divisions or subsidiaries of

major corporations which are among the largest in the United States.

Manufacturing facilities are highly concentrated in the central United

States. Exports of traction vehicles account for 30% to 45% of shipments of

total units while imports have historically been a minor factor. Eleven

manufacturers of crawlers and/or wheeled dozers are identified by Kearney as being currently active in the domestic market. Of these, nine are domestic

manufacturers, one manufacturer is a domestic company which imports most of

its units from foreign subsidiaries, and one manufacturer is strictly an importer. Table 2 gives an estimate of sales for these eleven

manufacturers

.

Manufacturers do not necessarily produce both crawlers and wheeled

dozers nor necessarily offer both large and small equipment. Tables 3 and 4

show the market segment of crawlers and wheeled dozers which are offered by

each manufacturer.

If loaders were included in the above tabulations of data, many more

manufacturers would be included. Lists of manufacturers of both dozers and

loaders compiled by General Motors Corporation[ 7 ] are reproduced as Tables 5 and 6. No breakdown of sales data presently exists in the public domain for

loaders

.

2.4. Design Characteristics

Engine horsepower and noise emissions are related. As size, weight and

horsepower of dozers and loaders are increased, noise emissions increase

also. The size of the construction site, more or less, dictates the size of

the equipment used on the site. Larger construction sites can more efficiently use larger construction equipment. Equipment that would be used

in vast remote areas, such as construction sites for dams and open-pit

mines, would be impractical in smaller areas, such as sites in

urban-residential areas near homes, schools, hospitals and other businesses.

Construction operations in urban-rural areas, such as roadway building and

factory site preparation, typically would use larger equipment than is used

in urban-residential areas but smaller equipment than is used in rural

areas

.

An assessment of spectator noise levels for dozers and loaders should

thus be based on the societal impact of the noise emissions from a particular dozer or loader, i.e., the cost/benefit ratio of noise control

measures. Equipment used in remote areas should not have as stringent a noise regulation as equipment used in urban residential areas. A logical

breakdown suggested by a major construction machine manufacturer [ 8

]

categorizes dozers and loaders with respect to engine horsepower since

5
Table 3

Crawlers offered by manufacturer by horsepower range[2].

Horsepower Range

Manufacturer 20-89 29-199 200-299 300 and Over

Allis-Chalmers* XXX X

J. I. Case X X

Caterpillar Tractor XXX X

Deere and Company X

International Harvester XX X

Komatsu Manufacturing XX X

Massey-Ferguson X

Terex X X

*Fiat-Allis

Table 4

Wheel dozers offered by manufacturer by horsepower range[2].

Horsepower Range

Manufacturer

Caterpillar Tractor

Clark Equipment

International Harvester

M-R-S Manufacturing

V-Con Division of

Marion Power Shovel

20-89 90-199 200-299 300 and Over

X

X

X

X

X

X

X

6
Table 5. Manufacturers distributing loaders and dozers in the U.S. [7].

Parent Firm

Division or Subsidiary

(Trade Name in Parenthesei)

Wheel

Loaders* (4-wheel Drive)

' Wheel

Dozers**

(Rubber-tired)

Tracked

Looders (Crawler loaders)

Tracked

Dozers

(Crawler tractors)

Allis-Chalmers Corp. Industrial Tractor Division X

Tenneco Corp. J.I. Case Co. X

Catepillar Tractor Co. U.S. Commercial Div. X

Clark Equipment Co. Construction Equipment Div. w

(Michigan) X

Pacccr Dart Truck Co. X

Deere & Co. Industrial Equipment Div. X

Eaton Corp. Construction Equipment Div. y

(Yale, formerly Trojan)

A

Ford Motor Co. Tractor Operations X

Fiat-Allis, Inc. (Fiat-Allis) X

International Harvester Pay Line Div. (Hough) X

Komatsu Ltd. Komatsu America Corp.

Marcthon Manu. Co. Marathon-LeTourneau Co.,

(Longvie-w Div. (LeTourneau))

X

* At -. - my—Co ~r" :c/"*r^ 1 ±f\ (Mos>ey-Ferguson and MasseyFerguson-Handmag)

X

Ovatonna Mfg. Co.- (Owatonna) (Mustang) X

General Motors Corp. Terex Div. X

Taylor Machine Words X

Marion Power Shovel V-Con Div.

JCB Ltd. JCB Excavators, Inc. X

X

X

A I

X

X I

X I X I X I

X

X

X

X

X

X I

Letter "I" indicates that one or more models are manufactured outside U.S. and imported for sale. Wheel looders are non-skid-steer, with bucket 1 cu.yd. or larger.

k Wheel dozers listed are rubber-tired only, excluding sanitary landfill compactor.

7
Table 6. Manufacturers distributing wheel loaders in the U. S.[7].

Parent Firm

Division or Subsidiary

(Trade Name in Parenthesis)

Four-Wheel

Drive

under 1 cu.yd,

Articulated

Two-Wheel

Drive

Any size

Allis-Chalrners Corp.

Aximuth Engr. Co. Tenncco Corp. Tenneco Ccrp.

Davis Welding & Mfg. Co.

Deere & Co. Dynamic !nH

.

Erickson Corp.

Ford Motor Co.

Geh! Co.

Bucyr us-Erie Hydra-Mac Inc. International Hcrvester Long Mfg. N.C. Inc. Massey-Ferguscn Ltd. Clark Equipment Co. Hy-Maric Corp.

JC3 Ltd. Sperry Rand Corp.

Cwatcnna Mfg. Co.

Koehring Co.

TCI Inc. TECO Crcb Inc. Thomas Equipment Ltd. Versatile Power Ccrp.

Waldon Inc. White Motor Corp.

Pettibone Corp.

Dkjrnore Equipment ^ Engro

Industrial Tractor Div.

J.I. Case Co.

Davis Div. of J.I. Case

Industrial Equipment Div.

Tractor Operations

(Hydraskat)

Hy-Dynamic Div. (Dyna Hce)

Pay Line Div.

Melroe Div. (3cbcat)

JCB Excavators Inc. Sperry New Holland Div.

(Owatonna) (Mustang)

Parsons Div.

(BRONCO)

Construction Equipment Div

X

X

X

X

X

X

X

X

Tractor- Loader Back-ho«

(2 or 4 whl dr)

X

X

X

X

X

X

X

X

X

Steer

(4 -wheel

drive)

X

X

X

X

X

X

X

X

X

X

X

X

8
horsepower bears some relationship to the area of use and also the noise

emitted. The suggested classifications and typical usage areas are:

1. 20 thru 150 hp - urban-residential areas

2. 151 thru 300 hp - urban-rural areas

3. 301 thru 600 hp - rural areas

4. 601 hp and up - remote areas.

3. Effects- of Noise and Parties Affected

Noise from construction equipment is the major cause of spectator noise

on a construction site. The persons who potentially are adversely affected

by the noise from construction equipment, including dozers and loaders,

include the operator— of the equipment or other workmen on the construction

site, passers by, and persons living or working near the construction site.

Construction noise can interfere with speech communication, lead to

distraction or other kinds of task interference, and potentially contribute

to the risk of hearing damage and other possible physiological effects.

4. Major Noise Sources

It is important to identify the major sources of noise in dozers and

loaders and the effect of normal operation on the noise levels associated

with each of these sources. Experience[l] has shown that the noise levels

generated by dozers and loaders depend more on horsepower than anything

else.

4.1. Engine Related Noise Sources

Since both construo-tion equipment and heavy duty trucks are powered by

diesel engines, many of the major engine-related noise contributors for

construction equipment are the same as for heavy duty trucks. The primary

difference lies in the location of the major noise components and the

shielding provided by the body. Basically the three major engine related

noise sources in the dynamic test mode[l] are, in order of predominance:

1. Fan Noise - is the result of air flow past the fan blades which

results in rotational (associated with pressure differences across

the fan blades) and turbulent noise (associated with the eddy

flows and vortices shed at the blade edges) . Such noise is

related to fan tip speed and to air distribution, which is

governed by the fan configuration and environment. It should be

noted that fan and radiator size is limited by visibility

requirements of the operator.

2. Engine (Mechanical) Noise - is primarily produced by the combustion process which produces rapid changes in pressure in the

— Operator noise exposure is covered by OSHA regulations and therefore, is

not included in the scope of this report.

9
cylinder which in turn results in excited mechanical vibration in

the engine structure. Some of this vibrational energy is subsequently radiated to the atmosphere as acoustic energy.

3. Exhaust Noise - is created when high pressure exhaust gases, re- leased through the engine exhaust valves, excite oscillations in

the exhaust system which are radiated to the atmosphere at the

tail pipe, through the pipe surfaces and through the muffler

shell. This noise is a function of engine type; engine timing;

valve duration time; intake system type; muffler type, size and

location; pipe diameter; pipe bends; dual or single system; etc.

Other engine related noise sources [1] include:

4. Air- Intake Noise - is created by the opening and closing of the

intake valve which causes the volume of air in the system to pulsate. Associated noise levels are dependent upon whether the

engine is gasoline or diesel, turbocharged or naturally aspirated,

2-cycle or 4-cycle, the number of cylinders, the engine displacement, engine rpm, engine load, etc.

5. Transmission Noise - arises from the meshing of gear teeth in

transmission systems and may be apparent under load, no load, or reverse load conditions. The noise may be aggravated by resonance

of the gearbox casing or by structure-borne components that excite

large body surfaces that act as efficient radiators.

Some examples of engine noise control techniques are given in

references 9 thru 18. The method of control for these sources is much the same as for diesel trucks with one major exception — cooling fan noise.

Diesel trucks, because of their high speed operating mode, depend mostly on ram air through the radiator for cooling, with a fan as a back-up.

Construction equipment, on the other hand, operates in a stationary or relatively slow moving mode and must depend more on the fan for forced air

cooling. While much can be done to shroud the engine and fan of a diesel

truck, the greater cooling efficiencies needed for construction equipment

prevent use of some of these treatments.

As machinery size increases, engine and cooling system noise of con- struction equipment becomes more difficult to control. Empirically, engine

and cooling fan noise increase with increasing engine horsepower at the rate

of approximately 3 and 6 dB per doubling of engine horsepower, respectively,

in the horsepower range of 200 hp.

A larger engine rejects more waste heat and requires a larger radiator

and air flow. For larger engines the optimum radiator and fan size for

noise control and cooling requirements cannot be used due to size limitations. The radiator frontal area cannot be proportionately increased with

engine size since it would then reduce operator visibility. Pressure losses

increase with engine horsepower and the advantage of increased fan diameter

10
with power is not fully realized.

Engine noises tend to radiate from (or excite) thin sheet metal parts

such as the oil pan or valve covers. Methods of reducing engine noise

include structural modifications to the engine block, changing thickness or shape of components and panels, or decoupling components from the exciting

forces

.

Exhaust noise of muffled engines is low in comparison with the other

noise sources and until the other sources are reduced, improved mufflers

would have a negligible effect. If exhaust noise is a problem due to a poor

muffler, improved mufflers offer a relatively inexpensive solution but again

there are size limitations based on operator visibility. Space in the

engine compartment is limited and the main muffler must therefore be

externally mounted.

4.2. Other Noise Sources

For tracked vehicles, track noise can be a major noise source,

especially during operation of the vehicle in the high speed reverse mode.

There is disagreement between industrial and other knowledgable personnel

concerning the percentage of time that the high speed reverse mode is used

during a normal work cycle. Industrial experts claim that high speed reverse operation is an atypical operating mode while those outside the

industry estimate that the high speed reverse mode is used 30-40% of the

time

.

Track noise is caused by metal-to-metal contact which produces

vibrations throughout the track. Utilizing present state-of-the-art noise

control technology, not much can be done to reduce track noise without

substantially increasing initial track costs and operating costs. One

existing quiet track system uses rubber bushed pins which replace the

standard straight steel pins. The familiar squeal caused by sliding motion

at the pin-bushing interface is eliminated and impacts of the track chain on idlers and drive sprockets are isolated within each track chain section. In

addition to the higher track cost, track life is reduced substantially.

Outside of this rather impractical approach to track quieting, the

technology to quiet track noise is lacking.

Additional sources of noise include hydraulic components as well as impulsive noises such as relief valve noise and banging buckets and blades — the level of which depend much on operator skill.

5. Typical Work Cycles

The test procedures used today do not measure average noise levels of

construction equipment but measure levels representative of the higher range

of sound levels generated by the machinery un^er actual operating

conditions

.

11
Industry representatives claim that, due to the multitudinous jobs performed by dozers and loaders, no meaningful average noise levels exist and

no typical work cycle can be established. Typical operation, it is claimed,

varies according to the material being moved. Moving rock, for instance,

creates more noise than moving a softer material such as dirt or sand. This

added noise is not a result of the machine doing more work, however, but

results from the interaction between the blade and material being moved.

When measuring noise emissions, one is not interested in the noise generated

by moving a particular material but is interested in the noise generated by

the loading on the engine of the dozer or loader. It should be noted that

engine loading does not depend on the type or consistency of the material

being hauled or pushed. For most efficient operation, the engine loading

should be at or near its maximum. Typical operating procedures, which

require doing the greatest amount of work in the shortest possible time,

thus call for maintenance of maximum or near maximum engine loading. For

example, to obtain the most efficient operation of a dozer, the blade is

lowered into whatever material is present until a torque converter stall

condition (maximum load) is reached. The material is then moved. Less

hard-packed dirt would be pushed than sand in a typical operation, but

loading of the engine for either operation would be the same. The noise

emitted due to engine loading would also be the same.

Typical work cycles are being considered for operator noise level

measurement standards by the SAE Construction Noise Subcommittee. There

seems to be no reason why, then, that a typical work cycle cannot be

established for spectator noise regulations, provided the noise generated as

a result of the machine's interaction with the material being moved does not

predominate

.

6. Existing Measurement Procedures

The test procedures contained in six existing documents could be

utilized to measure noise emissions from wheeled and tracked dozers and

loaders. They are:

1. SAE Recommended Practice J88a, Exterior Sound Level Measurement

Procedure for Powered Mobile Construction Machinery .[ 19

]

2. French Decree No. 69-380, Limitation of the Sound Level of Airborne Noise Emitted by Internal Combustion Engines in Certain

Construction Equipment. [ 20]

3. German Regulation, Noise Limits for Track Type Tractors [21] (currently being revised)

.

4. German Regulation, Noise Limits for Wheel Loaders [22] (currently

being revised)

.

5. ISO Draft Proposal for Acoustics - Determination of Airborne Noise

Emitted by Earth Moving Machinery to the Surroundings - Survey

12
Method. [23]

6. ASA Standard 3-1975, Test-Site. Measurement of Noise Emitted by

Engine Powered Equipment [24]

.

Of these six documents, only the American Standards, SAE J88a and ASA

3-1975 , and the French Decree are in their final form. With the exception

of ASA STD.3-19"7 5 (permission to reprint this standard was not granted by

ASA), complete texts of these standards are reproduced in Appendix A. To

better facilitate a discussion of these measurement procedures table 7 has

been developed which outlines the pertinent sections of each of the test

methods. This table serves as the basis for comparison among the six

procedures

.

The SAE recommended practice is intended to measure noise emissions

which are repeatable and representative of the higher range of sound levels

generated by the machinery under actual field operating conditions. These

levels do not necessarily represent the average sound level over a typical

use cycle. The standard consists of a series of stationary and moving tests

which are designed to assure that all possible noise producing elements of

the machine are measured.

The stationary tests include measurements at a distance of 50 feet

(15.2 m) from the machine on all four sides for the following no load test

conditions

1. Wide open throttle

2. Low idle-maximum governed speed-low idle

3. Wide open "mottle including activation of the appropriate

hydraulic dircuits and other drive systems.

Fan and mechanical noise emissions are measured during the wide open

throttle test; the low idle-maximum governed speed-low idle loads the engine

such that engine noise, airborne and s tructureborne noise, and exhaust noise

emissions can be measured, and the wide open throttle test which includes

activation of various drive systems allows one to measure hydraulic and

hydrostatic noise emissions.

The dynamic tests are designed to check gear train and track noise

emissions by driving the machinery through a measurement zone at wide open

throttle in an intermediate gear for an unloaded, empty unit. Measurements

are made for the right and left side of the vehicle at a distance of 50 feet

(15.2 m).

The ASA standard specifies measurement methods for determining the

maximum noise emitted by a variety of engine powered equipment. For

construction and industrial equipment the test procedures are very similar

to SAE J88a test procedures with the most notable exception being the

13
Table 7. Comparison of existing and proposed measurement procedures for determining the exterior noise of dozers and loaders.

Standard SAE J88a ASA STD 3-1975 French Decree 69-380 German Regulation SO Draft ISO/TC 43/SC1 !Secretariat-190) 260

Vehicles Covered Powered mobile c n- struction equipment

of 20 rated blip and over

Motor vehicles, public conveyances, construction and Industrial machinery, residential

and recreational

vehicles powered by engines operating

on petroleum-based

fuels, coal, steam, electricity, or other source of energy

All construction

equipment equipped with internal com- bustion engines

other than automotive vehicles

track type tractors

and wheel type loaders

larth moving machinery

1 ns t rumen tat Ion 1) Type 1 sound

level meter meeting

req ui rements of

,

ANSI SI .4-1971—

2) Alternative measurement system

meeting requirements

of SAE J184^'

sound level meter meeting requirements

of ANSI SI .4-1971—

Type 1 for certification, Type 2 for enforcement or survey

sound level meter meeting requirements

of French national, standard S 31 009^

sound level meter meeting requirements

of ANSI SI. 4-1971-

Type.,1 and IEC

tound level meter meeting

"equi rements of IEC 179—

ind appropriate octave

liters meeting requirelents of IEC 225^

Test Site Flat open space

free of obstructions within 100 ft (30.4 m) of either microphone or machinery

open space of uni- form grade not ex- ceeding 2 % average

and free of reflecting surfaces other

than ground plane within 30 m (100 ft) from either microphone or machinery

open area free of obstructions within

25 m of equipment

under test

flat open space

free of obstructions wi thin 30 m from machine being tested

: lat open space free

)f obstructions within

iO m from machine being

:ested

Measurement Area Surface hard packed earth—

smooth concrete or smooth sealed

asphalt or similar material

flat concrete, asphalt or similar hard material, hard packed^earth or groundconcrete or impervious asphalttrack type tractor — packed, moist,

sandy loom soil

wheel type loader — concrete, asphalt

or hard packed earth

lard packed earth—

isphalt, concrete, or

similar hard surface

Testing Modes moving and stationary moving and stationary stationary moving, stationary,

work cycle

noving and stationary

Length of Vehicle

Path

66 ft (20 m) 30 m (100 ft) 20 meters 10 meters

Microphone Location (Moving

Tests)

50 ft (15.2 m) from major side surface

parallel to machine

path, each side, and

4 ft (1.2 m) above, ground plane

15 m (50 ft) from vehicle centerllne

each side and 1.2 m (4 ft) above ground plane

•

10 meters on both

sides of centerline

of machine path,

and 1.2 meters

above surface on which machine is located

7 meters from each

sides of reference

parallelepiped of

i/ehicle and 1.5 meters

above ground level

Microphone Location (Work Cycle) track type tractor — 10 meters on both

sides of centerline

of machine path, and

1.2 meters above sur- face on which machine

is located

wheel type loader — 10 to 20 meters on both sides of centerline of machine path

depending on length

of machine, and 1.2 meters above surface

on which machine is located.

Vehicle Operation

(Moving Tests) forward intermediate

Rear ratio at no

load at full governor control setting

(for vehicles capable of speeds over

25 km/hr (15 mph) full throttle acceleration mode

and closed throttle deceleration mode covering at least upper one-third of engine speed range

track type tractor — highest speed re- verse at full open governor control. Also work cycle

test mode.

wheel type loader — forward gear so governor control

fully open max. speed less than 15

maximum governor setting in forward inter- mediate gear at no

Load. If vehicle

designed to operate in forward-reverse shuttle

mode, both forward and reverse used.

14
Table 7 (continued)

Standard SAE J88a A5A StD 3-l$75 French Decree 69-38( German Regulation

Whr (9.8 mph) with bucket filled with sand. Also work cycle test mode

.

ISO Draft ISO/TC 43/SC1 (Secretariat-190) 260

i/ehicle Reference

Point (Moving

Tests)

unspecified front of vehicle leading and trailing edges of machine in test zone

when some part of machine is within measurement length

•licrophone Location (Stationary

Tests)

50 ft (15.2 m) nor- mal to center of major surfaces of machine and 4 ft (1.2 m) above ground plane

15 m (50 ft) from centerline of vehicle path in direction giving greatest sound level and 1.2 m (4 ft) above ground plane, also

15 m (50 ft) above ground plane above vehicle centerline

if suspected that appreciable energy radiated upward from equipment

7 meters from engine casing or

part of equipment

that take its place , and 1 . 5 neters above

ground

8 positions around machine, 7 meters

from sides and corners of imaginary box over machine

including bulldozer

blade' and 1.2 meters above surface

on which machine

is located

6 positions around

machine, 7 meters

from sides of imaginary box over machine on centerline. 4 positions

at 1.5 meters above surface 2 positions on sides

at 7 meters above surface

Vehicle Operation

(Stationary

Tests)

no load in neutral maximum governed

speed, low icle- maximum governed

speed-low idle, hydraulic circuits activated

(for vehicles having a maximum speed

less than 25 km/hr

(15 mph) and equipment used inside factories or other industrial applications, and auxiliary

equipment) rated engine speed no load maximum power and other combinations of load and speed or operating modes which would produce

greater sound, if practicable ; full throttle no load, idle to engine rated

speed

io load, governor

?r speed control

set to give maxinum full-load

gpeed

high idle speed at full open governor position

cycle from low idle to maximum governed speed

at no load, maximum

governed speed, hydraulic

circuits activated while

at maximum governed speed

Quantity Measured Maximum A-weighted

sound level, slow response

Maximum A-weighted

sound level, fast response

Maximum A-weighted

sound level, slow

response

Maximum A-weighted

sound level, fast response

Maximum A-weighted

sound level , s low response

Reported Value For cycling and moving tests, average of two values within 2 dB of each otner for noisiest microphone position.

(For stahle tests only one reading)

Moving tests: sound level for noisier side and noisier mode of operation

.

Stationary tests

maximum level obtained

.

nighest level recordedstationary mode- arithmetical average, drive-by mode - arithmetical average of 4 readings

(2 each side)

,

Work cycle-arithmetical average both

readings

for each mode, each

location , calculated

mean, and A-weighted

sound power level, background level if correction applied

.

1. American Standard Specification for Sound Level Meters, ANSI-SI. 4-19 71 , (American National Standards Institute, New York, New York), 1971.

2. SAE Recommended Practice Qualifying a Sound Data Acquisition System - SAE J184

(Society of Automotive Engineers, Warrendale, Pa.), 1970.

3. Acoustique, Sonometres de Precision, Objet de la Norme , French National Standard

S 31 009, (available from American National Standard Institute, New York, New York) September 1968.

4. International Electrotechnical Commission Recommendations for Precision Sound

Level Meters, Publication 179 (available from American National Standards Institute, New York, New York), 1973.

5. International Electrotechnical Commission Recommendations for Octave, Half-Octave, and Third-Octave Band Filters intended for the Analysis of Sounds and Vibrations, Publication 225 '(available from American National Standards Institute, New York, New York), 1966.

6. For moving teats of all steel wheel, steel drum or track type machines.

7. For moving tests of all steel wheel and track vehicles, optional for rubber

tired vehicles.

15
specified microphone iocation for stationary tests. In the ASA document,

preliminary measurements are made to locate that position 15 meters (50

feet) from the vehicle where the sound level is maximum. Sound level

measurements are made at this position. Further comparison can be made by

reviewing the respective entries in Table 7.

The French Decree specifies measurement of noise emission at a distance

of 7 meters (25 ft.) from the engine casing on four sides, while the

machinery is operating at wide open throttle. As stated before, this test

allows measurement of the noise emissions from the fan and mechanical

systems. No tests are specified in the French Decree for measuring exhaust,

gear train, track, hydraulics or hydrostatic noise emissions. For large

equipment the 7 meter (25 ft.) distance from the engine casing can dictate a measurement location which is impractical, i.e., a location within the

bounds of the machinery.

The two German regulations establish a machine work cycle test mode

where the machinery performs its main function of carrying (a loader) or pushing soil (a dozer) in addition to stationary and moving tests similar to

the wide open throttle and drive-by tests of the SAE standard. The work

cycle described in these regulations, however, doesn't appear to approximate

typical work cycles.

The. ISO draft proposal specifies essentially the same series of

stationary and moving tests as the SAE document. Measurements are taken at

four locations, each 7 meters (25 ft) from the machinery surface (only side

locations for moving tests) . The mean A-weighted sound level is determined

for both stationary and moving tests. As an option, the A-weighted sound

power level may also be determined for the stationary test mode.

In addition to the previously discussed measurement procedures, there

exists an ISO draft proposal entitled "Determination of Airborne Noise

Emitted by Civil Engineering Equipment for Outdoor Use" [25]. This is a generic standard- developed by the European Economic Community (EEC) and

follows the International trend of specifying the estimation of sound power

level for all stationary tests. Another nearly identical generic standard

has been developed by ISO -- ISO/DIS 3744 - Acoustics - Determination of

Sound Power Levels of Noise Sources - Engineering Methods for Free Field

Conditions Over a Reflecting Plane[26]. The relationship between these two

generic standards (draft) and their relationship to yet-to-be-developed test

codes is not clear at this time.

— A generic standard specifies procedures for the measurement and/or

determination of the acoustic quantity to be measured regardless of the

noise source. Such a standard requires the generation of test codes for

specific noise sources which specify the operating and/or mounting con- ditions of the noise source and the microphone array.

16
7. Data Base and Correlations

A review of the literature and discussions with knowledgeable industry

personnel reveal a limited data base in the public domain[l ,2] . Engineering

data have been collected by manufacturers of construction equipment, but it

is mostly proprietary in nature. Many manufacturers utilize SAE J88a test

procedures in part of their program to gather engineering data of noise

emissions from construction machinery. SAE J88a appears to be a good

engineering tool for the manufacturer but no data base yet exists to assure

that test procedures suggested in SAE J88a and other (foreign) standards are appropriate for regulatory purposes.

It appears doubtful that proprietary data which have been obtained by

the construction industry are sufficiently extensive to provide EPA with

even a substantial fraction of the information needed for a comprehensive

analysis of the economic costs and technical feasibility associated with a given regulation. Furthermore, it is evident that there are practically no data available upon which to base an evaluation of alternative dozer and

loader noise measurement procedures or to establish correlations between the

noise associated with various operational modes and the noise measured

utilizing various test procedures.

Thus, it appears that EPA will have to generate a rather extensive

physical data base and investigate alternative measurement procedures prior

to formulation of the Notice of Proposed Rule Making.

8. Overview of Dozer and Loader Noise Measurement Difficulties

The information discussed in Sections 2 through 7 of this report serves

as the basis for an overview of dozer and loader noise measurement problems.

Utilizing that information with the discussions of this section, potential

noise measurement problems that could hinder the promulgation and/or

enforcement of future noise regulations to control noise emissions from

dozers and loaders are identified.

Prior to the establishment of an appropriate measurement procedure that

can be utilized for determining the exterior noise of dozers and loaders,

certain informational requirements must be satisfied. These include: (1) a product classification scheme based on where the equipment is used, (2) a product classification and identification scheme indicating which specific

pieces of equipment are to be covered, (3) typical work cycle data including

the effects of operation and environment on noise levels, and (4) the

societal impact of dozer and loader noise on people and the nature of this

impact. Such data allow one to select, with confidence, the acoustical

quantity to be measured, the operational mode of the vehicle, and the

locations for microphones which need to be specified in the regulation.

Test site specifications and instrumentation requirements also hinge on the

availability of this fundamental information.

8.1. Probable or Potential Measurement Difficulties

The measurement problems which exist in the determination of noise

17
emissions from wheeled and tracked dozers and loaders are extensive and

varied. They range from procedural problems — measurement difficulties,

availability of test machinery, costs associated with testing — to availability of test space.

8.1. a. Representative Noise Regulations

Perhaps the most serious problem is the lack of a data base on typical

work cycles with which to facilitate the establishment of proper test procedures. All of the test procedures which exist today appear to be good

engineering tools for the manufacturer but unless validated their

application to enforcement of noise regulations should be questioned. They

all measure noise emissions which represent the higher range of sound levels

generated by the machinery under actual field operating conditions. These

levels do not necessarily represent the average sound level of the machinery

over a field-use cycle.

A philosophy must be developed regarding the quantity to be measured

and the rationale behind this philosophy must satisfy the intent of the

Noise Control Act of 1972. For instance, if average noise levels are selected, a typical work cycle must be developed. Selection of a typical

work cycle will be difficult due to the varied uses of identical equipment.

Once measurement procedures are established, a substantial data base is

needed.

8.2. Classification

Some of the factors associated with establishment of dozer and loader

classes based on engine horsepower have been discussed in Section 2. The

main purpose for dozer and loader classification in conjunction with noise

regulations is to set different noise limits on different categories of

dozers and loaders either because of the potential societal noise impact of

a particular class of dozers and loaders or because of economic cost and

technological feasibility of noise control as applied to the various classes

of dozers and loaders.

At present, reasonable divisions of dozer and loader classes based on

use can be made by classification according to horsepower; however, the

resultant noise level characteristics of each class over the range of normal

operation are not presently known.

8.3. Machines to be Tested

Particular problems in testing may arise due to the nature of the

products and the way they are sold. Testing may be difficult for many

machines which require final assembly at a facility other than the main

manufacturing plant — such as a dealer's or customer's facility. Reasons

for final assembly at other facilities are many and varied — (1)

multi-plant facilities may exist in which all parts are shipped directly to

18
the dealer for final assembly (2) attachments to the base machine may be

designed and constructed by an independent manufacturer and installed by the

dealer or customer (3) back ordered items may be delivered to the

construction site and installed, and (4) some machines may just be too large

to be transported by truck or rail when fully assembled. Economic

considerations lead to many foreign made machines being shipped unassembled.

Thus, testing at the manufacturer's facility may require expensive

assembly and disassembly for large vehicles, and may be impossible or impractical for other unassembled machines. Testing at foreign

manufacturing facilities may present audit and control difficulties.

Testing cannot easily be performed on stockpiled vehicles until sale is

eminent. Many stored vehicles, for which no immediate sale is assured, are

not equipped with tires, blades, buckets, or other attachments. Since tires are quite expensive and deterioration would prevent sale of a tire, special

mounts are used to support the machine while in storage. Blades, buckets

and other attachments are not installed since their inclusion or not is the

decision of the eventual customer.

It should be possible for testing to be performed on the base machine

without attachments (but with tires) and meaningful results obtained;

however, data are necessary to support this assumption. In general, the

effect of an attachment is to slightly shield noise being generated from

behind the attachment. With an attachment raised, this shielding would not occur so it is questionable whether more meaningful results would be

obtained when the attachment is present. Hydraulic noise emission testing

may be hampered, however, if the hydraulic drive equipment is part of the

attachment. In some cases, hydraulic drive units are attached to the base

machine even though the attachment is not installed. These units could be"

operated for noise emission testing. The question of whether meaningful

data could be obtained with this sort of testing should be explored.

Even testing a base machine (tractor without attachments) for

compliance with a regulation may be difficult. Seemingly identical machines

may have different components due to geographic availability; especially

where foreign counterparts of American machines are manufactured by the same

company. These components may change the noise characteristics of the

machine. In addition, though basic models may exist for 6-8 years,

evolutionary changes are continually being made. After 6 years or so the same machine might be completely different even though it will bear the same model number. Continual monitoring of changes would be necessary to assess

the effect on noise emissions.

8.4. Test Site

Test site considerations have both practical and measurement implications. Approximately 1.5 acres of land is needed for an outdoor test site

if moving tests are required. If not presently owned, the purchase of this

land can be quite costly, especially if the manufacturing facility is in an urban area. Because of transportation problems associated with large

equipment, it is desirable to have on-site testing facilities.

19
In urban areas, manufacturing plants are typically property line-toproperty line facilities, that is, no land is available for expansion let

alone for noise testing sites. Other industrial activities generally

surround the facility, sometimes presenting uncontrollable noise sources which can severely disrupt attempts at testing for noise emissions.

In rural areas land may be available at present but, due to the

changing environmental scene, what is rural today may be urban tomorrow.

Freeways or other industrial plants may emerge causing the same problems

that now exist in urban areas. The manufacturing plants own expansion plans

may even have to be altered to facilitate an outdoor area for moving tests.

Exclusive of land, one manufacturer estimates that expenditures of (for

paving, measuring equipment, etc.) from $100k - 200k would be needed to

develop a test site to comply with SAE J88a requirements. A stationary test

requirement would not only cut down costs of site construction and equipment

tremendously but more importantly would reduce the necessary land area as well

.

A paved surface is presently favored for machine testing. Potentially

a paved surface would yield more reproducible results than would be possible

over a dirt surface. Testing over paved surfaces typically give higher

sound level readings than dirt due to the reflective characteristics of the . harder surface but to what extent correlation exists between tests conducted

on dirt and tests conducted on paved surfaces is not known at present. The

major problems associated with testing over a dirt surface occur due to the

everchanging surface conditions caused by previous test vehicle traffic

(especially with tracked vehicles) or environmental conditions such as rain

or drought which can vary surface conditions. Test results are thus less

likely to be reproducible.

In addition, dirt surface testing results in expensive clean-up

procedures for tracked vehicles. Before a tracked vehicle can be sold it is

necessary to remove all of the dirt and mud which has been compacted between

the track and track guides during the noise tests. This job typically takes

from three to eight hours per machine. The clean-up job must be thorough

since the track area must then be repainted.

There is a great need to explore a variety of proposed test plans —

paved versus dirt, stationary versus moving, etc. — in order to evaluate

the good and bad features of each. One must also consider the future

testing needs of the manufacturer. Regulations for other types of

construction equipment will undoubtedly emerge. To avoid unnecessary

expense to the manufacturer, the testing facility should be large enough to

accommodate, and be compatible with, the testing needs of other construction

equipment such as scrapers and haulers.

8.5. Quantity Measured

The EPA "levels document" utilizes the equivalent A-weighted sound

20
level as the appropriate quantity to use in characterizing noise exposure.

Thus, it would be desirable if the quantity (or quantities) measured in a regulation on a specific noise source, e.g., a dozer or loader could be

easily and directly related to the contribution which the source makes to

the equivalent A-weighted sound level for typical listeners.

It seems evident that a comprehensive experimental program is needed to

guide and justify the development of the measurement procedure — whether

maximum sound levels for several operational modes or an average sound level

based on a typical use cycle. The presence of discrete pure tones and/or

impulsive component noises typical of dozers and loaders should be examined

to aid in determining if these noises should be accounted for.

8.6. Acoustic Environment

There appears to be general agreement that the noise emission from

motor vehicles should be measured in a free field over a reflecting plane.

If a 50 foot (15.2 m) measurement distance is utilized, a rather large open

area is needed plus a roadway of sufficient length to accomodate the

specified operational mode(s) of the vehicle.

Although considerable uniformity of testing has been achieved by the

SAE and ISO in defining standard noise measurement procedures, there remains

a small but important variation between noise measurements made at different

sites, or at different times at the same site. Experience to date with

measurement of motor vehicle noise at 25 to 50 foot (7.6 to 15.2 m)

distances, for typical microphone heights, indicates that the levels

measured are sensitive to the characteristics of the surrounding ambient

(air temperature, humidity, atmospheric pressure), to the characteristics of

the reflecting plane (acoustic impedance, flatness), to temperature

gradients above the plane (which depend on present and past air

temperatures, sunlight, and wind velocities as well as the emittance and

absorptance of the reflecting plane), and to atmospheric inhomogeneities

(wind velocity and local turbulance) . All of these factors influence the

generation of noise by the propulsion system and associated auxiliary

equipment, the radiation from the source into the surrounding atmosphere

and/or the propagation from the immediate vicinity of the vehicle to the

measurement location.

Since these factors influence reliable measurements of many of the sources which EPA is, or will be, regulating, there is a need for the

various environmental and site effects to be systematically investigated so

that: (1) noise measurements taken at a given site can be corrected to

standard environmental conditions, (2) noise measurements taken at different

sites under the same environmental conditions can be correlated and

therefore (3) noise measurements taken at different sites under any

environmental conditions can be correlated. If correction factors are not

feasible then there is a need for a site calibration procedure and/or

definition of limiting test conditions.

21
8. 6. a. Constructive and Destructive Interference Effects

When stationary mode measurements are performed with fixed source and

receiver heights, constructive and/or destructive interference between the

direct and reflected signals from the machine noise sources can result in an increase/or reduction of the signal sound level at the location of the

receiver, respectively. With a source of large physical size and a wide

spectrum of emitted noise the effects of these ground reflections are not as serious as with a small source and a pure tone.

8.6. b. Heat Radiation

Though no data exist in the literature, temperature effects caused by

heat radiation from the engine can cause measurement problems during

stationary tests. A bubble of hot air can surround the equipment if

conditions are right. Wind can shape this bubble in different ways thus

causing measurement inconsistencies due to changes in the noise generation

mechanisms and noise radiation to the surrounding environment.

8.6. c. Cooling Fan Wind Generation

Another measurement problem can be caused by the cooling fan of the

equipment. When measurements are made with a radiator directing the air

flow from the cooling fan toward the microphone, air movement can reach high

velocities, even at a distance of 50 feet. A study should be made to

determine if the velocity of this fan-generated wind is sufficient to hamper

the measurement being made.

These are just some of the factors which should be addressed. In

general, these are factors over which one has little or no control.

8.7. Instrumentation

The instrumentation section of the regulation should require equipment

meeting the Type 1 requirements of American National Standard Specifications

for Sound Level Meters, S1.4-1971[27] . In addition, pertinent sections of

American National Standard Methods for the Measurement of Sound Pressure

Levels, SI. 13-1971[ 28] should be incorporated. For instruments for which

standards do not exist, or where existing standards are not sufficient, the

regulation should include specific criteria for evaluating the performance

of such devices. For example, a critical deficiency in existing standards

is that the response of instrumentation to transient signals is not well

defined.

It is important to clearly state in the regulation the allowable

tolerances for frequency response, environmental effects, harmonic

distortion, etc., which the instruments are required to meet. These

specifications should be applied not only to specific components of the

system but to the overall system as well. Regardless of the instrumentation

22
configuration, the overall system measurement error should not be degraded

below that allowed for measurements made directly with a sound level meter.

In addition, overall system calibration should be required at frequent

stipulated intervals. The fact that each component of a system appears

satisfactory does not ensure that the system performance will be acceptable.

8.8. Current Versus Alternative Test Procedures

8. 8. a. Current Test Procedures

The SAE J88a test procedures (which are the only procedures presently

utilized in the United States) require a minimum of 34 readings as shown in

Table 8. The implementation time for these stationary and moving tests can

be reduced somewhat if space and instrumentation is available to place

microphones on all four sides and take simultaneous measurements. Though

manpower and/or instrumentation requirements are increased substantially

testing time could be reduced to a minimum of 10 tests [29].

The low idle-maximum governed speed-low idle test included in SAE J88a

is designed to provide a simple stationary test. This test procedure was added to SAE J88a in the hopes that future data obtained from this test

would substantiate data that has already been validated for diesel trucks.

For trucks, this procedure has been shown to be a repeatable, meaningful,

stationary test.

Industry claims that the stationary test modes specified in SAE J88a do

not give representative data. They claim that the wide open throttle and

low idle-maximum governed speed-low idle test modes may result in governor

overshoots resulting in abnormally high engine and fan speed conditions. - Correspondingly higher noise emissions result which are not representative

of actual use conditions.

A torque converter stall test mode — which had been specified in

previous test procedures but was eliminated from SAE J88a — could be used

to load the engine against the transmission torque converter and replace the

wide open throttle and low idle-maximum governed speed-low idle test modes.

The main disadvantage of the torque converter stall test mode is that it can

not be used on machines with manual transmissions and thus can not be

applied uniformly to all loaders and dozers — a necessity for compliance

testing.

With a stationary test, track noise (in the case of tracked vehicles)

is of course, not measured. As discussed previously, the technology to

quiet track noise is minimal at present. One wonders why, then, it is

necessary to measure track noise. If a regulation is based on the maximum

measured noise emitted from a machine then the most predominant noise for

tracked vehicles would probably be track noise. Other noise emissions would

be predominant during stationary modes or low speed operation (i.e., over

60% of the time for a typical operating cycle of a dozer or loader) . These

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other sources would essentially be unregulated since they would probably be

lower than the minimum track noise that can be accomplished by present

technology and there would be no incentive to quiet these other sources. Tt

would appear to be more prudent to base a maximum permissible sound level

regulation on noise emissions other than track noise until state-of-the-art

track noise control is more prevalent and more practical — noise emissions

which could most likely be checked by a stationary test. The overall noise

level of the dozer or loader would thus cause less societal impact since the

noise level would be lower for 60 percent or more of the time at least.

8.8.b. Alternative Test Procedures

The public interest probably could better be served by a simple less

costly test than SAE J88a that could be effectively utilized to determine

the noise potential of construction machines such as dozers and loaders.

Such a test would hopefully better approximate the sound energy emitted

under actual working conditions which constitutes a potential impact on the

public rather than the single maximum value from SAE J88a which may not be

representative of actual working conditions. A simpler test should be more

appropriately applicable to a production compliance program.

A simpler test that includes only stationary testing would avoid the

large expenses associated with land acquisition and test site preparation.

A stationary test suggested by the construction industry [30] involves

measuring the noise emissions from a machine while the engine is operating

at rated RPM. Measurements made over a standard surface at locations 50

feet (15.2 m) from the right and left of the machine are suggested. Limited

data, as shown in Table 9, shows that measurements for the right and left

hand sides only will closely approximate the average of all four sides for

the machines tested. In addition to reducing the number of measurement

positions, the need for attachments, i.e., blades, buckets, etc., to be

installed is eliminated. Other limited data[30] indicate that except for

track noises, the stationary tests produce higher noise levels than passby

tests. These data also show hydraulic noise levels that are consistantly

lower than the noise from other components. Industry claims that a stationary test at engine rated rpm approximates actual use conditions

better than the tests of SAE J88a. This claim should be verified through an extensive test program.

Though a great need exists for all weather availability of a test

facility — namely an indoor facility which would give a good correlation

between experimental and actual use data, the sizes of equipment, in

addition to dozers and loaders, which must be accomodated would require

prohibitive cost outlays. It should be noted that if the estimation of

sound power is deemed appropriate in the case of stationary tests, then the

feasibility of utilizing close-in measurements should be evaluated in order

to ease the test site requirements. The appropriateness of close-in

measurements has been shown to be valid in the case of portable air

compressors [ 31]

.

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26
9- Appendix A. Existing Loader and Dozer Measurement Procedures—^

EXTERIOR SOUND LEVEL MEASUREMENT

PROCEDURE FOR POWERED MOBILE

CONSTRUCTION EQUIPMENT - SAE J88a SAE Recommended Practice

Report of Vehicle Sound Level Committee approved

November 1972 and last revised June 1975.

1. SCOPE-This SAE Recommended

Practice sets forth the instrumentation and procedure to be used in

measuring exterior sound levels for

powered mobile construction equipment of 20 rated bhp and over. It

is not intended to cover operation

of safety devices (such as backup

alarms) air compressors, jack hammers, and machinery designed primarily for operation on highways or

ily for operation on highways or within factories, aircraft, or re- creational vehicles such as snow- mobiles and boats. The sound levels

obtained by using the test procedures set forth in this SAE Recommended Practice are repeatable and

are representative of the higher

range of sound levels generated by

the machinery under actual field

operating conditions, but do not

necessarily represent the average

sound level over a field use cycle.

2. INSTRUMENTATION

2.1 A sound level meter which

meets the Type 1 or S1A requirements

of the American National Standard

Specification for Sound Level Meters,

SI. 4-1971.

2.2 As an alternative to making

direct measurements using a sound

level meter, a microphone or sound

level meter may be used with a magnetic tape recorder and/or

graphic level recorder or indicating instrument, providing the system

meets the requirements of SAE Recommended Practice J184 QUALIFYING A

SOUND DATA ACQ"IS J^ION SYSTEM.

2.3 An ac^ astical calibrator (see

paragraph 4.2.4 — accuracy within /

0.5dB)

2.4 A microphone windscreen shall

be used that does not permit the

effect on the microphone and frequency response to exceed / 0.5 dB

to 5kHz and / 2 . OdB to 12 kHz.

2.5 An anemometer or other device for measurement of ambient wind

speed and direction (accuracy within £ 10%)

2.6 A power source rpm indicator (accuracy within £ 2%)

2.7 A thermometer for measurement of ambient temperature (accuracy within / 1°)

2.8 A barometer for measuring

atmospheric pressure (accuracy within £ 1%) . 3.1 Test Site - The test area

shall consist of a flat open space

free of any large reflecting surfaces

such as a signboard, building or hillside, located within 30m (100ft)

of either the microphone or the

machinery being measured (see Fig.l).

It is recommended that measurements

be made only when the wind speed is

below 19 km/h (12 mph*

3.1.1 The minimum measurement

area (see Fig. 1) shall consist of

the triangle formed by the microphone location, points A & B, and

the rectangle formed by points A,

B, C & D. Both designated areas

shall be smooth concrete or smooth

and sealed sphalt or a similar hard

and smooth surface. The rectangle

formed by points C, D, E & F shall

consist of hard-packed earth. The

planes between the microphone location and line AB and planes encom- passed by points A, B, C, F, E & D

shall form a continuous, uniform

plane. If a minimum measurement area

test site is used, it will require

reorientation of the machine for

each major surface measurement during the stationary tests, and the

movina test will have to be run in

two opposite directions. The other

option is to have a larger measurement area test site and relocate

the microphone for the series of

prescribed test conditions with the

machine in one position for stationary tests and driving by in only

one direction for the moving tests.

3.1.2 Because bystanders have an appreciable influence on the meter

response when they are in the vicinity of the construction machinery or

^Reprinted with permission, ^"Copyright ©Society of Automotive Engineers,

Inc., All rights reserved."

27
NOTE B.JO(OO) RADIUS DIMENSIONS tft Ml FT)

FIG. 1 - TEST SIT CONFIGURATION

microphone, not more than one person,

other than the observer reading the

meter, shall be within 17m (56 ft)

of the construction machinery and

1.8m (6ft) of the measuring microphone, and that person shall be

directly behind the observer who is

reading the meter, on a line through

the microphone and the observer (see

Fig. 1).

3.1.3 The ambient sound level due

to sources other than the construction machinery being measured ( including wind effects) shall be at

least 10 dB lower than the sound

level of the machinery being measured,

(see paragraph 3.3.3).

3.1.4 The surface between and under

the construction machinery and microphone shall be smooth and free of

acoustically absorptive material,

such as snow or grass.

3.1.5 For all stationary tests the

machinery shall be located on the

hard surface area formed by points

A,B,C&D in Fig 1. 3.1.6 Moving Tests

3.1.6.1 For moving tests of all

rubber tired machines, the path of

travel shall be across the area defined by points A, B, C & D in

the directions shown in Fig. 1. 3.1.6.2 For moving tests of all

steel wheel, steel drum or tracktype of machines the path of travel

shall be across the area defined

by C, D, E & F in the direction

shown in Fig. 1.

2H
3.2 Tests Required

(a) For mobile construction

machinery that is used primarily in

a stationary mode, test per paragraphs 3.2.1.1, 3.2.1.2, and if applicable 3.2.1.3.

(b) For self-propelled con- struction machinery that is used

primarily in a mobile mode, test

per paragraphs 3.2.1.1, 3.2.1.2,

3.2.1.3, and 3.2.2. For construction

machines which have an auxiliary

power source, such as a truck mounted

crane, the main engine and auxiliary

engine shall be run separately during

tests 3.2.1.1 and 3.2.1.2 with the

other engine shut down. During test

3.2.1.3 only the auxiliary engine

shall be run and only the main propulsion engine run during the test

prescribed in 3.2.2. For combined

construction machinery (such as small

loader with backhoe) test per paragraphs 3.2.1.1, 3.2.1.2, 3.2.1.3

and 3.2.2.

3.2.1 Stationary Tests with Ground

Propulsion Transmission Shift Selector

in Neutral Position.

3.2.1.1 Operate all mobile con- struction machinery engines at no load with all component drive systems

in neutral position and maximum

governed speed (high idle at no load)

at a stabilized condition.

3.2.1.2 Operate all mobile con- struction machinery engines at no load with all component drive systems

in neutral position through the

cycle "low idle-maximum governed

speed (high idle at no load) low

idle" as rapidly as possible, but

allowing the engine to stabilize for

at least 10 sec at maximum governed/

speed (high idle at no load) before

it is permitted to return to low

idle.

3.2.1.3 With the engine at the

maximum governed speed (high idle at

no load) in a stabilized condition,

activate the appropriate hydraulic

circuits, mechanical, electrical,

hydrostatic, or torque converter

drive systems to cycle the major

components or component from the most

retracted and/or lowered position to

fully extended and/or maximum height

position and then back to orginal

position. This cycling should be

done as fast as practical, taking

into consideration all the pertinent

safety factors/that can be accom- plished without blowing relief

valves. For safety reasons and

undesirability of change of location of major noise source in relation to microphone, a major portion

of the mobile machine, such as the

tractor of a scraper unit, drum of

a compactor, or the upper rotational

structure of an excavator, shall not

be moved or placed in a vibratory

mode of operation during this stationary machine test.

3.2.2 Constant &pe.&d moving Te.it —

Self-propelled construction machinery

shall be operated in a forward intermediate gear ratio at no load at a location as specified in paragraphs

3.1.6.1 or 3.1.6.2. The power source

shall be operated at full governor

control setting. Intermediate is

intended to mean second gear ratio

for machines with three or four gear

ratios, third gear ratio for machines

with five or six gear ratios, fourth

gear ratio for machines with seven

or eight gear ratios, etc. (Gear

ratio refers to overall gear re- ductions.) If there is a problem

with the transmission shifting up or down in this phase of this test, one

gear lower or higher may be used to

eliminate the problem. Hydrostatic

or electric drive machinery will be

operated as near as possible to onehalf its maximum ground speed.

Machinery that has major noise-generating components which could be

used at the above ground speed, such

as on an elevating scraper or on a vibrating compactor, shall have

these major components in operation

during this movinq test.

3.2.3 Construction machinery that

has a major attachment that is

normally used for the main operating

function shall be equipped with this

attachment. Examples of this are buckets on loaders and dozers on either wheel or track-type tractors.

For all tests these attachments

shall be in a minimum transport

position of 0.15m (6 in) to 0.3 m

(12 in) for dozers, scrapers, etc.,

and for loaders use carry position

as specified by SAE Standard J732

SPECIFICATIONS DEFINITIONS-FRONT

END LOADER.

3.3 MEASUREMENTS
3.3.1 The microphone shall be

located at a height of 1.2m (4 ft)

above the ground plane.

3.3.2 The sound level meter shall

be set for slow response and the A-

"weighting network.

3.3.3 The ambient wind speed and

direction, ambient temperature,

atmospheric pressure, and ambient Aweighted sound level shall be

measured and recorded at the height

of 1.2m (4 ft) and within at least

3m (10 ft) of the one specified

location of the microphone as shown

in Fig. 1.

3.3.4 The stabilized maximum

governed engine speed shall be

measured and recorded.

3.3.5 The sound level meter needle

movement shall be observed during

each test sequence at the specified

microphone location. The highest

value observed, disregarding sounds

of short duration that are out of

character with the test on the

machine, (example) impact sound such

as bucket rack against stops, shall

be recorded for each test sequence.

For stabilized test conditions (3.2.

1.1) a single reading shall be re- corded for each measurement point.

For cycling and moving test conditions (3.2.1.2, 3.2.1.3 and 3.2.2)

a minimum of three readings shall

be taken for ea"ch measuring point.

If none of these readings are within

2 dB of each other, then additional

readings shall be taken until there

are two that are within 2 dB of each

other. The reported value shall be

the average of these two values that

are within 2 dB of each other. If

there are two pairs of readings that

are within 2 dB of each other, report

the average of the higher pair. The

final reported result for each test

mode shall be the highest reading for

stabilized test conditions and the

highest average for the cyclic or moving tests and must include the

location of the microphone.

3.3.6 For stationary tests, record

the sound level obtained at a distance of 15m (50 ft ) normal to the

centers of the four major surfaces of

the equipment at the microphone

height. Generally, four major surfaces refer to front, rear, and sides

of an imaginary box that would just

fit over the machine but does not

include attachment items such as buckets, dozers, and booms (see Fig.

2) . In the case of a crane or an exTV

EH

VTRACK c

FIG. 2 - MAJOR SURFACE OUTLINES
cava tor, the upper (revolving superstructure) fore-and-aft centerline

should be in line with the lower

fore-and-aft centerline. Operate the

machine in a manner as specified in

paragraphs 3.2.1.1, 3.2.1.2 and 3.2.

1.3.

3.3.7 For moving tests, take

leasurements at a distance of 15m

(50 ft) measured in a direction

normal to a major side surface which

is parallel to the machine path, as shown in Fig. 1. Operate the

machine in a manner specified in

paragraph 3.2.2.

3.3.8 The final reported sound

level per this SAE Recommended

Practice shall be the highest of the

reported values obtained in paragraphs 3.3.6 and 3.3.7; the test re- port shall include the test mode,

the machine operating conditions

during the reported test mode, the

stabilized maximum governed engine

speed, the location of the microphone in relation to the construction machine, the surface description over which the machine operated and the sound level measurements

were made

.

4.1 It is recommended that

persons technically trained and ex- perienced in the current techniques

of sound measurements select the

instrumentation and conduct the tests.

4.2 Proper use of all test instrumentation is essential to obtain

valid measurements. Operating manuals

or other literature furnished by the

instrument manufacturer should be

referred to for both recommended

operation of the instrument and precautions to be observed. Specific

items to be considered are: 4.2.1 The type of microphone which

shall be oriented with respect to the source so that the sound strikes the

diaphragm at the angle for which the

microphone was calibrated to have

the flatest frequency response

characteristic over the frequency

range of interest.

4.2.2 The effects of ambient weather

conditions on the performance of all

instruments (for example: temperature,

humidity, and barometric pressure)

.

Instrumentation can be influenced

by low temperature, and caution

should be exercised.

4.2.3 Proper signal levels, terminating impedances, and cable lengths

on multi-instrument measurement

systems

.

4.2.4 Proper acoustical calibration

procedure, to include the influence

of extension cables, etc. Field

acoustical calibration shall be made

immediately before and after each

test sequence of a piece of con- struction machinery.

5. REFERENCES

5.1 ANSI SI. 1-1960 (R1971)

,

Acoustical Terminology

5.2 ANSI SI. 2-1962 (R1971)

,

Physical Measurement of Sound

5.3 ANSI SI. 4-1971, Specification for Sound Level Meters

5.4 ANSI SI. 13-1971, Methods

for the Measurement of Sound Pressure Levels

5.5 ISO R362, Measurement of

Noise Emitted by Vehicles

5.6 SAE Recommended Practice

J184, Qualifying a Sound Data

Acquisition System

5.7 SAE Standard J732c-Specification Definitions-Front End

Loader

5.8 C.A.G.I. - PNEUROP Test

Code for Measurement of Sound for

Pneumatic Equipment

Applications for copies of ANSI and ISO documents should be addressed to:

American National Standards

Institute, Inc.

1430 Broadway

New York, New York 10018
Official Journal of the French Republic

2 May 1972 Pages 4535-4536

LIMITATION OF THE SOUND LEVEL OF AIRBORNE NOISE EMITTED BY

INTERNAL COMBUSTION ENGINES IN CERTAIN CONSTRUCTION EQUIPMENT

In view of the decree No. 69-380 of April 18, 1969 relative

to the soundproofing of construction equipment;

And in view of the order of 25 October 1962 relative to the

measurement of noise produced by automotive vehicles,

Now all proclaim:

bftsLLcJLo, 1 - All construction equipment equipped with internal

combustion engines, other than automotive vehicles coming under the

requirements of the order of October 25, 1962 mentioned above, if

manufactured or imported more than one year following the effective

date of this order, may be used on construction sites, whether public

or not, only if they are equipped with devices to quiet the intake and

exhaust of the engines.

The airborne noise produced by the engines of this equipment,

measured as prescribed in the accompanying annex, shall not exceed

80 dB(A) at a distance of 7 meters. Derogations can be granted by the

Minister for the Protection of Nature and the Environment, however, for

a period of, at most, one year.

krutLcJLt 2 - Construction equipment with internal combustion

engines, manufactured or imported before the effective date of the

requirements of the first paragraph of article 1 above, may be used

at locations less than 50 meters from buildings used as dwellings, or for work, or reserved for any other human activity only if:

They are fitted with devices to quiet the intake and

exhaust of the engines within two years after the

effective date of the present order; and

32
They meet the requirements of the second paragraph of

article 1 within five years after the effective date

of the present order.

AAJtidlz 3 - Interministerial orders can define, for different

categories of construction equipment and operating conditions, the

permissible OV&i&Lt sound levels; the sound levels fixed by article

1 above refer only to the noise of the internal combustion engines.

In this case, the measurements of noise produced by the engines

alone, prescribed in article 4 will not be necessary.

Article. 4 - Construction equipment such as described in article 1 will be certificated as to their sound output by the Minister for the

Protection of Nature and the Environment.

This certification is to be based on measurements of the sound

output carried out, according to the method prescribed in the accompanying

annex, by laboratories approved for this purpose by the Minister for the

Protection of Nature and the Environment.

The certification is made either by type or for individual items

of equipment. For engines that can be adapted to various items of

construction equipment without modification of their intake and exhaust

silencers, the certification can be issued by type for the engine

itself, rather for each item of construction equipment on which it is

used

.

Manufacturers and importers of construction equipment should address

their requests for certification to approved laboratories, who will

forward them, along with the measurement results, to the Minister for

the Protection of Nature and the Environment.

Manufacturers and importers must furnish with the equipment a certificate of certification or an affidavit of conformity with a certificated model, according to a form given in the annex to this order.

33
AsvticZe. 5 - Laboratories wishing to conduct sound output measurements

in accordance with this order should request that they be approved for

this purpose by the Minister for the Protection of Nature and the

Environment, and should furnish detailed information on their facilities

and measurement capabilities. Such approval will be pronounced, if it is

given, by a decree of the Minister. It can be withdrawn at any time,

upon notification of the interested laboratory on the same form, without

previous notice or compensation.

A/i£cc/e 6 - The components of the equipment envisaged in article 1,

and particularly the silencing devices and their protective covers, must

be maintained in good condition or replaced if necessary, in order that

the noise emitted by said equipment does not exceed the levels prescribed in article 1.

AsutLdlz 7 - The present order will be published in the Official

Journal of the French Republic. Signed on 11 April 1972, in Paris

[by the ministers named at the beginning or their delegates].

AM/EX to the Order of 11 April 1972 relative to the limitation of

the sound level of noises emitted by internal combustion engines of

certain construction equipment.

RECOMMENDATIONS FOR DETERMINING THE AIRBORNE NOISE EMITTED BY

INTERNAL COMBUSTION ENGINES OF CERTAIN CONSTRUCTION EQUIPMENT

The present Recommendation establishes the method for determining

the airborne noise emitted by internal combustion engines of certain

construction equipment. It also defines how to analyze the test data

and how to present the results.

1. MeoAuAemeitt AppaAcutuA

The measurements shall be made with a sound level meter and

associated microphone meeting the requirements of French National

Standard S 31 009. The measurements should be made with A-weighting

and slow dynamic characteristic. The apparatus should be suitably

calibrated

.

34
2. EnviAonmant &oi thz TzAtb

The equipment shall be set up in an open area. No large object,

such as buildings or machines, should be located within 25 meters of

the equipment under test; if this is impossible, their position should

be described in the test report.

The equipment shall be placed on a hard reflecting surface, of

concrete or impervious asphalt, whose diameter is such that the

microphone positions, defined in paragraph 5 below, all lie within

this surfaced area. The microphone should not be near any reflecting

surface. The operators and the test equipment should be located at

least 1 meter from both the microphone and the equipment under test.

The measurements should be made with little or no wind.

3. Ba.ckgiou.nd Uo<Uz LzvoJL

The conditions for measuring the background noise and the corresponding

corrections to be subsequently applied to the test data are prescribed by

paragraph 6.3 of the French National Standard S 30 006 (June 1966).

4. OpeAcutLon the. EquU.pmo.nt UndeA TdAt

The Equipment under test shall be brought up to temperature and

operated in a stable regime.

The measurements should be made with no load, but with the governor

or speed control set to give maximum full- load speed, as specified by the

manufacturer

.

5. Location o& the. MejOAuAm&nt PoAjJxonA

Readings of the sound level should be made at four points around

the engine, at a distance of 7 meters from the engine casing or the

sides of the equipment that take its place, and at a height of 1.50

meters above the ground.

The four points should be situated on two perpendicular axes; if

the engine axis is horizontal, one of the measurement axes should be

parallel to it.

35
6. TnteApti&t&tion o& tkt ReAtrfU

The value retained to characterize the noise of the engine should

be the highest sound level recorded.

In case that value should be slightly higher than the maximum

permissible value, a second measurement should be made at the location

in question. If the result of the second measurement exceeds the value

prescribed in article 1, the equipment will be deemed not to conform to

the requirements of the present order.

7. PtieAzntation o£ RqauIXa

The test report shall give the following information:

a. Description of the equipment and test conditions (Mark, model,

serial number, principal dimensions and operating conditions of the

engine, atmospheric conditions at the time of the test).

b. Sketch indicating the test area and showing the location of

the measurement positions, as well as the direction and distance of

any large objects within 25 meters of the engine under test.

c. Mark, model and serial number of the acoustical measuring

equipment used, including the windscreen if necessary.

d. Background noise level.

e. A-weighted sound levels for the four measurement points.

36
AFFIDAVIT

of Conformity of construction equipment equipped with one or more

internal combustion engines with a certificated model (Applies to the

order of 11 April 1972)

The undersigned company (1)

certifies that the construction equipment hereafter designated:

Mark: Type: Serial Number:

Type of engine in the equipment: Maximum effective

sound level: conforms to the model tested for certification

No. dated in compliance with

the requirements of the order of relative

to the limitation of the sound level of noises emitted by internal

combustion engines in certain construction equipment.

Signature

Date

(1) The trade name and the main office address of the company should

be given.

37
10. References

1. Patterson, W. N. and Freeze, T., Traction Vehicles: Noise and Cost of

Abatement, (Bolt Beranek and Newman, Inc.) Report No. 2566b submitted

to the Environmental Protection Agency, Washington, D. C, January

1974.

2. Anon., A study to determine the Economic Impact of Noise Emission

Standards in the Construction Equipment Industry, (Traction Vehicle

Report by A. T. Kearney, Inc.) submitted to the Environmental Protection Agency, Washington, D. C. August 1974.

3. Identification Terminology of Earthmoving Machines - SAE 1057b, SAE

Standard (Society of Automotive Engineers, Warrendale, Pa. ) June 1975.

4. SAE Standard J173, Specification Definitions - Dozers, (Society of

Automotive Engineers, Warrendale, Pa.) May 1970.

5. SAE Standard J731c, Nomenclature - Loader (Front End) (Society of

Automotive Engineers, Warrendale, Pa.) May 1968.

6. SAE Standard 732c, Specification Definitions - Front End Loader,

(Society of Automotive Engineers, Warrendale, Pa.) October 1968.

7. Cherne, K. D. , Senior Project Engineer, Vehicular Noise Control,

(General Motors Corporation), Private Correspondence, August 22, 1975.

8. Anon. , Spectator Sound Level Test Data, Proposed Equipment Classification, Proposed Spectator Sound Levels for Mobile Earthmoving Equipment,

(Caterpillar Tractor Co.) Internal report submitted to the

Environmental Protection Agency, Washington, D. C. October 1973.

9. Nagel, A. E., A Noise Control Study of Certain Construction Equipment

Vehicles, (Mining Enforcement and Safety Administration, Pittsburgh,

Pa. ) .

10. Giovanetto, J., Reducing Noise After the Fact, Automotive Engineering,

Vol. 20, No. 9, September 1972.

11. Jenkins, S. H. and Kuebner, H. K. , Lowering Diesel Noise Through

Hardware Modifications, Automotive Engineering, Vol. 81, No. 6, June

1973.

12. Jenkins, S. H. , Lalor, N. , and Grover, E. C, Diesel Engine Noise Can

be Reduced, Automotive Engineering, Vol 81, No. 1, January 1973.

13. Tiede, D. D., and Kabole, D. F. , Quieting the Diesel with Structural

Changes, Automotive Engineering, Vol. 80, No. 12, December 1972.

14. Stephenson, N. J., and Thomas, I. D. A., Reduction of Noise from

Construction Machines with Particular Reference to Cooling Systems,

Noise Control and Vibration Reduction, February, 1975.

38
15. Anon., Sound Reduction Application, 72-71 and 72-81 Loader, (Terex

Division of General Motors, Hudson Ohio), Pub. 72SP20.

16. Anon., Sound Reduction Application, 72-21, 31, 41, 51 Loader (Terex

Division of General Motors), Hudson, Ohio, Pub. 72SP19.

17. Anon., Sound Reduction Application, Crawlers, (Terex Division of

General Motors) , Hudson, Ohio, Pub. 72SP18.

18. Sanders, C. E., A Contractors Approach to Noise Control of Off-Road

Vehicles, Noise Con 73 Proceedings, Institute of Noise Control

Engineering, Washington, D. C. , October 1973.

19. SAE Recommended Practice J88a, Exterior Sound Level Measurement

Procedures for Powered Mobile Construction Machinery (Society of

Automotive Engineers, Warrendale, Pa.) September 1974.

20. French Decree No. 69-380, Limitation of the Sound Level of Airborne

Noise Emitted by Internal Combustion Engines in Certain Construction

Equipment, Recueil des Textes Relatifs au Bruit - Nol383, Edition mise

a jour au 15 aout 1972, Journal Officiel de la Republique Francoise,

26, rue Desaix, 75732 Paris, CEDEX 15, France.

21. German Regulation, Noise Limits for Track Type Tractors (currently

being revised) (Tief dau-Beruf sgenossenshaf t , 8 Munchen 60 Am-Knie 6,

Germany)

.

22. German Regulation, Noise Limits for Wheel Loaders (currently being

revised) (Tief dau-Berufsgenossenshaf t , 8 Munchen 60 Am-Knie 6,

Germany)

.

23. ISO Draft Proposal for Acoustics - Determination of Airborne Noise

Emitted by Earth Moving Machinery to the Surroundings - Survey Method,

Draft Proposal ISO/TC43/SC 1 (Secretariat -190) 260, December 1974.

24. Acoustical Society of America Standard, Test-Site Measurement of Noise

Emitted by Engine Powered Equipment, ASA STD 3-1975 (Acoustical Society

of America, New York, New York) 1975.-'

25. International Organization for Standardization draft proposal,

Acoustics - Determination of Airborne Noise Emitted by Civil

Engineering Equipment for Outdoor Use, ISO/TC43/SC1 (Secretariat - 191)

261.

26. International Organization for Standardization draft international

standard, Acoustics - Determination of Sound Power Levels of Noise

Sources - Engineering Methods for Free Field Conditions Over a Reflecting Plane, ISO/DIS 3744.

— ASA 3-1975 was submitted to the American National Standards Institute for

approval for publication as ANSI SI. 19 but was rejected in its present form.

39
27. American National Standard, Specifications for Sound Level Meters, ANSI

SI. 4-1971 (American National Standards Institute, New York, New York.)

1971.

28. American National Standard, Methods for the Measurement of Sound

Pressure Levels, ANSI - SI. 13-1971 (American National Standards Institute, New York, New York) 1971.

29. Bergs ten, L. D., Exterior Sound Level Measurement Procedure for Powered

Mobile Construction Equipment, Noise Con 73 Proceedings, Institute of

Noise Control Engineering, Washington, D. C, October 1973.

30. Cherne, K. D., Senior Project Engineer, Vehicular Noise Control,

(General Motors Corporation), Private Correspondence, June 27, 1975.

31. Holmer, C. I., Procedures for Estimating Sound Power From Measurements

of Sound Pressure: An Experimental Investigation with Application to

Noise from Portable Air Compressors, NBSIR 75-652, EPA-550/8-76-001

,

National Bureau of Standards, Washington, D. C, November 1975.

USCOMM -NBSOC 40
NBS-1UA (REV. 7-73)

U.S. DEPT. 0 F COMM.

BIBLIOGRAPHIC DATA

SHEET

1. miHl.K A 1 ION OK REPORT NO. NBSIR 75-965

No.

3. Recipient's Accession No.

4. TITLE AND SUBTITLE

An Evaluation and Assessment of Existing Data and Procedures

for the Measurement of Noise from Dozers and Loaders

5. Publication Date Oct. 1975

6. Performing Organization (-ode

7. AUTHOR'S)

Thomas L. Quindry

8. Performing Organ. Report No. NBSIR 75-9b5

9 PFRFORMING ORGANIZATION NAMF AND ADDRFSS

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

10. Project/Task/Work Unit No. 2000451

11. Contract /Grant No.

12. Sponsoring Organization Name and Complete Address (Street, City, State, ZIP)

U. S. Environmental Protection Agency

Washington, D. C. 20460

13. Type of Report & Period

Covered

final

14. Sponsoring Agency Code

15. SUPPLEMENTARY NOTES

16. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significant

bibliography or literature survey, mention it here.)

This report reviews existing construction equipment noise measurement procedures with

regard to their usefulness in the regulation of noise from dozers and loaders as well as the availability, extent and applicability of existing data. On the basis

of this review, probable or potential measurement difficulties are identified that

could hinder the promulgation and/or enforcement of future EPA regulations to control

the noise emission from dozers and loaders.

17. KEY WORDS (six to twelve entries; alphabetical order; capitalize only the first letter of the first key word unless a proper name; separated by semicolons)

Acoustics (sound); dozer; loader; measurement methodology; noise emission standard,

noise measurement.

18. AVAILABILITY [~1 Unlimited

[Xj For Official Distribution. Do Not Release to NTIS

Order From Sup. of Doc, U.S. Government Printing Office Washington, D.C. 20402, SD Cat. No. C13

[

I Order From National Technical Information Service (NTIS)

Springfield, Virginia 22151

19. SECURITY CLASS

(THIS REPORT)

UNCL ASSIFIED

20. SECURITY CLASS

(THIS PAGE)

UNCLASSIFIED

21. NO. OF PAGES

46

22. Price

USCOMM-DC 29042-P74