The Tyranny of Noise

Robert Alex Baron

Part III — Chapter 7 — The Politics Of Noise

One of the more subtle stratagems used by the noisemakers to frustrate noise control has been called The Weighting Game by Jim Botsford of Bethlehem Steel. It stems from the seemingly innocent fact that a small group of noise specialists have become more interested in measuring noise than abating it. To the physical scientist, and the psychologist and sociologist who fail to see the total human being, nothing—including human suffering—exists unless it can be quantified and made to fit into a formula.

Acoustical scientists and technologists embarked on a search for the ultimate measurement of the human "annoyance" response to noise. Esoteric "annoyance" measurements and formulae are devised to try to tell the noisemaker how much noise he can make before the victim yells ouch, how much noise he can make before the victim is moved to active protest.

Central to all schemes for measuring "annoyance" is the decibel.

At one time it was believed that loudness was the determining factor in measuring noise. Most anti-noise ordinances were based on common sense—they prohibited noises that could be described as "unreasonably loud."

With the advent of the decibel meter and its variations, the noise specialist refused to accept the personal complaint of "it's too loud." He began to search for a precise formula, a formula to be based not on individual complaints, but on group judgments. The acousticians preferred to wrestle with statistics instead of noise complainers.

Specialists called psychoacousticians started out by trying to quantify the subjective response to noise in terms of loudness. Experiments were devised to try to measure how loud is loud. Juries of listeners were exposed to various levels of noise and asked to rate them as soft or loud, or to compare two sounds as equal or differing in loudness.

As the field of psychoacoustics developed, it was discovered that loudness is only one of many factors that make noise annoying. There followed a proliferation of decibel varieties that continues to this day.

Not content with the pristine decibel, already only an indirect measurement of sound energy, the acoustic power structure, under government contract, embarked on a search for the acoustic holy grail, the ultimate decibel and decibel formula of its limited concept of the human response to noise.

The measurement specialists made a new "discovery": it was not loudness that determined annoyance, but "noisiness." Thus was born the family of perceived noise decibels (PNdBs). Developed originally to apply to aircraft noise, this family is a fertile one; its apparently well-financed promoters come up with one refinement after another. For example, we are told that annoyance varies with the number of noise exposures (such as the number of airplane flyovers), and with the degree of pure tones in a given noise. To account for these variables, the experts have developed a variety of effective perceived noise decibels.

The goal in the use of PNdBs is not a comfortable environment, but one with a minimal number of complaints. The modified PNdBs would make it appear, for example, that less annoyance from fewer aircraft flyovers is the same as no annoyance. Will the use of jumbo jets solve the jet noise problem?

There is now an attempt to add a new decibel-weighting to the readings on the sound level meter, the "D" decibel. Acousticians Robert W. Young of the U.S. Navy and Arnold Peterson of the General Radio Company studied this new "improvement" and concluded: "There is no justification for adding D-weighting to the sound level meter. For simple noise reporting and comparisons the public will benefit, at no loss in precision, if only sound level"A" is employed."

The fragmentation of noise measurement units is what Jim Botsford calls The Weighting Game. Botsford has been sharply critical of this racket in numbers, since he sees such complex measurements as a deterrent to hearing conservation programs in industry. "Methods for estimating the hazard to hearing must be made as simple as possible," he says. After a thorough study of the various schemes for predicting annoyance, speech interference, and hearing loss, this noise control physicist concluded: "The complex methods currently recommended for appraising the effects of noise on people can be replaced by simpler methods utilizing the readings of a standard sound level meter. The small errors introduced by these substitutions are negligible compared to those inherent in the relationship of noise measurements to human response." Botsford pulls no punches in describing how the public is paying, in discomfort and in money, to support The Weighting Game. In a report the magazine Sound and Vibration published in October 1969, he wrote:

Human responses to noise can be predicted from sound levels as from any of the more complex noise rating numbers currently recommended...It is highly improbable that the foregoing facts could have escaped discovery under the intense scientific scrutiny that human responses to noise have received. Yet, sound levels are shunned and the development of complicated noise weighting methods continues. This inconsistent and unproductive behavior implies that motivations other than elucidation of human response may spark the investigator's fervor...The activity related to the interactions of people and noise might really be just a game.

The principal players in The Weighting Game are the Researchers, the Consultants, The Noisemakers, and the Public. Each player has his strategy and his winnings except the Public who loses steadily.

Botsford summarizes the Game in a table:

Player Strategy Winnings
Researcherrefines weighting methods endlesslyresearch contracts, publications, etc.
Noisemakerlacks information, supports research, waiting for answersexpense of noise abatement postponed
Consultanthelps clients use weightingsfees
Publicwants problem solvednone, pays bill

Referring to this table, he comments: "This program will prove helpful in identifying the players as they are encountered in the field. Masqueraders are quite common in The Weighting Game so, for positive identification of a player, his strategy and winnings must be examined. Often, what appears to be a Researcher will be identified as a Noisemaker by his strategy and his winnings."

No matter how complex, annoyance measurements remain of limited value. Yaffe and Cohen of the Public Health Service state: "While of some value, perceived noise decibels and other annoyance measurements based upon single judgments of the noise stimulus are expected to have only limited usefulness in gauging the complaint potential of a noise. This is due to the many non-acoustical considerations which enter into such judgments."

Herein is a semantic ploy of the first water, because the uninformed are led to believe that what is being measured is the total human response to noise. But the subjective reaction of annoyance is not the total human response to noise. Conscious annoyance is but a symptom that the human being is disturbed; it is not and cannot be an accurate measure of the extent of that disturbance. (See Chapter 3.)

Loudness, perceived noise, "A" or "D" decibels concentrate on one small aspect of the human response to noise: conscious awareness of irritation. Ignored in the formulae are the effects of noise on sleep, on the emotions, and on the biological processes.

Does it make sense to worry about the nuances of decibels when the receiver is experiencing noise in the 90- and 100-decibel range? Because the prolonged barking of a dog disturbs sleep, we enact ordinances to compel dog owners to keep their pets quiet at night. These anti-barking codes do not specify the size of the dog, or the decibel level of the bark, or even the use of perceived barking dog noise decibels (PBDNdBs). It is accepted that sleep must be protected, and that barking disturbs sleep. Yet when it comes to jet planes or trucks, or air conditioners, all of which can and do disturb sleep, we are asked to wait for the perfect measurement. One of the standing jokes among the noise experts is that the elaborate decibel measurement systems are necessary because the degree of decibel reduction is so minuscule it cannot be detected by simple means!

Enough is known about the physical nature of noise to control it. There is no valid reason for not abating noise first, and measuring it during or afterward.