NOISE

SOLUTIONS BY GREG ZAK

36

BJRCH

DRIVE

CiiATIIAi~4,

ILLINOIS

62629

(217) 483-3507

(217) 483-5667-FAX

E-mail:

e~zak~justice.com

P

~

February

5,

2003

Iffinois Pollution ControlBoard

J. R. Thompson Center

Suite 11-500

100

West Randolph Street

Chicago, Illinois 60601

RE:

NOISE RULE UPDATE:

AMENDMENTS TO

35

ILL. ADM. CODE 900 and 903; R03-8

Dear Board Members:

Listed below are my comments to

the proposedNoise Rule Amendments:

Section

900

103 Measurement Procedures

b) ProceduresAppliéable oniytó

35

III. Adm.

Code 901

The one-hour L~is

ftir too

long for virtually all

situations.

The vast majority of noise

sources

complained about in

Iffinois when measured by the

Leq

method produce the

same decibel reading

whethermeasured fora minute or two or a fullhour. A fewexamples ofnoise sources producingthe

same decibelresult whether measured for less than a minute or a fttll hour are:

ventilation fans, air-

conditioning chillers, idling heavytrucks, aerationfins at grainhandling facilities, fanson nearlyall air

pollution control devices.

Measurements should be

made in accordance with American National

Standards Institute Quantities and Procedures for Description and Measurement ofEnvironmental

Sound, Part 3:

Short-termMeasurementswith an Observer Present.

This Standarddescribes howto

measurethe noise source ofinterest and correct forthe presence ofbackground sound.

We suggest

adding S12.9 Part 3

as item E in the list ofStandards included with this clause and in 900.105.

The text should read:

1)

All measurement and all measurementprocedures to

determine whether emissions ofsound

comply with 35

III. Adm.

Code 901

shall with the exception ofmeasurements to determine

whether

emissions of sound comply

with 35

III.

Adm.

Code

901.109,

be

based

on

Leq

averaging,

as defined in 35

III. Adm.

Code

900.101

using a period of observation that

is

---

Illinois Pollution Control Board, February

.~‘,

z.’.i~..

2

commensuratewith the variability

of the

soundin question. Ifthe sound is steady,thena one-

minute period ofobservation is sufficient; ifthe sound is non-steady, thena longer period of

observation may be required until the level measured does not vary by more than plus or

minus

0.5

dB.

All suchmeasurements and measurements procedures for

Leq

must correct, or

providefor thecorrectionofsuchemissions, forthe presence ofambient orbackground noise

in accordance with the procedures in 35 Ill. Adm. Code 910.

Althoughnot includedas amendments, there are other areasthat should be reviewed formodification.

The measurement procedure currently contained in the Rules for impulsive sound, Section 901.104,

require the use ofthe one-hour L~.Previous to the Board’s adoption ofthe one hour

Leq in 1987,

impulsive soundwas measured from 1973 to

1987 using fast dynamic characteristic meter response.

Fast dynamic characteristicmeter response uses an averaging time of

0.125

seconds.

Comparing an

averaging time of0.125 seconds(fast dynamic characteristic) to 3600 seconds (one hour

Leq)

reveals

a

difference

of 28,800

to

1

when

comparing

the

pre-1987

methodology

to

the

post-1987

methodology. The one-hour

Leq

requirement for impulsive noise has made it impossible to measure

due to an extremely long averaging time fora noise event ofextremelyshort duration. The generally

accepted way to measure impulsive noise is to utilize sound exposure level (SEL).

The averaging

time for SEL

is one

second.

Illinois should require the use of SEL just as it used to

require fast

dynamic characteristic formeasuring impulsive

sound in Section 901.104.

Another areafor consideration is the adjustmentforimpulsive sound.

The Rules currently indicatea

5

dB adjustment forgeneral impulsive sound.

Under ANSI S 12.9 Part

1, there is a 12 dB adjustment

for“highly impulsive” sounds” (which includesgunfire, metal hammering, and woodhammering) and

a

5

dB

adjustment

for “regular impulsive”

sounds.

For “high energy impulsive”

sounds

(which

includes quarry and mining), there is a separate procedure.

These same impulsive adjustments and

procedures are contained in ISO 1996 Part 2, Amendment

1 and in thenewly draftedISO 1996 Part

1

Final Draft International Standard.

The Illinois Rules should be consistent and adopt these same

types ofadjustments and procedures, especially sincethey reference ANSI

S 12.9 Part

1.

Sincerely,

Greg Zak,

CE, MA

cc:

Mr. Howard China