Noise Gets the Nod as "Arch Enemy No. 1"

Noise Gets the Nod as "Arch Enemy No. 1"
Operators look at various ways to reduce decibels

By Lisa Arnseth

Controlling noise levels in a tunnel wash is necessary to protect employees, safeguard customers, prevent neighbor complaints and avoid possibly being cited for OSHA violations. But it isn't always easy.

OSHA regulations state that noise monitoring is necessary when employees are subject to noise levels at or above 85 decibels (dB) during an eight-hour workday. Since the average industrial dryer measures in between 75 and 110 dB, carwashes may have to conduct tests to measure sound levels to determine if employees need to be issued protective earplugs or if equipment itself needs to be modified.

Joel Jurkens, vice president of Octopus Car Wash in Albuquerque, NM, says his washes were actually fined by OSHA for not complying with noise regulations. OSHA had done personal sound level monitoring and found that Jurkens' wash had a sound environment of 97 dB, which was considerably higher than the limit. "We had a sign that stated that hearing protection was available," says Jurkens, "but apparently that's not sufficient. Once you get over a decibel level of 92 for an eight-hour period then you have to force the employees to wear the ear protection." Today Jurkens pays to have his employees' hearing screened every six months in a sound-proof trailer.

Changing the facility

The dryer is generally considered to be the loudest piece of equipment inside the tunnel. Although many of today's models have been quieted down, some still sound much like a hurricane.

Operators can take some sound-deadening steps during construction. By lining the walls of the tunnel with sound-muffling materials and re-arranging their set-up, the stormy sounds can often be lowered to a dull roar.

In some locations, operators who could not meet compliance have been forced to buy all new blowers. But often adding baffles to the dryers themselves or insulating the walls against sound is enough to do the trick. Bob Paisner of the ScrubaDub Auto Wash Centers in Natick, MA heard complaints from residents across the street that one of his washes was too noisy. In response he added plastic baffles to the blower system. Since that time, he says the manufacturers have jumped onto the noise-reduction train and manufacture their systems with sound baffles already incorporated.

Paisner also found that curtain doors he had installed to keep cold air out of the tunnel were also helping to quiet sound. "When the door opens again, yes it's noisy. But when it's closed it has a huge effect on deadening sound outside," he says.

Using paneling on the walls can help as well. During construction phases of new washes, installing very thick insulation and then attaching sound board underneath drywall will help contain tunnel noise. It's important not to overlook the ceiling as well, and acoustical sound tiles are often enough to act as a sound barrier. Metal strips designed to attach to drywall through the studs work well at reducing sound's ability to travel through walls.

If changing the walls of the facility is not feasible or simply does not cut noise enough, many operators are opting to move the motor of the dryers to another location so that the sound environment of the tunnel is not as harsh. At the Quality Car Washes in Holland, MI, owner Tom Essenburg has dryers that pump out 160 horsepower using four 40-horsepower motors. To handle the excessive noise, at different locations he has placed some of the dryers in the basement or in side equipment rooms or storage rooms.

"The equipment room has insulation on the wall to deaden sound, and the ceiling has been insulated--this has been very effective for noise reduction," he notes. In addition to cutting sound, having the motors in separate rooms makes for easier access and servicing. Essenburg says he has never had a problem with OSHA and believes his dryer configuration makes for a strong system. "We are very happy with this arrangement," he says.

Jurkens says he knows of several operators who have gone the re-configuration route. "You take the impellers and the motors and you build that separate room that's soundproof, and then you just duct it out to the wash area," says Jurkens.

OSHA says noise can be measured using monitoring equipment that can be purchased or rented from safety equipment companies. The two types of monitoring include area monitoring, which is appropriate when noise level remains constant and employees stay in relatively the same place, and personal monitoring. In personal monitoring, the employee wears a microphone on his or her clothing called a dosimeter, which measures and records sound level throughout the day. (This personal monitoring can also be done with a sound level meter, but this tends to be more complicated since this method calls for an individual to carry the meter and follow the employee.)

While this type of monitoring does not need to be done on a regular basis, OSHA says re-monitoring must be done if there is new equipment or changes in equipment that may affect employees' hearing.

Dryer Noise--A Necessary Evil?

By Tracy Charuhas

Stricter noise pollution standards in many states and overall concern for customer and employee comfort are making dryer silencers and other noise suppressing methods a necessity. Silencers, sound dampening wall/ceiling materials and location of dryers in a tunnel all affect dryer noise levels.

While silencers will reduce the noise level in a carwash tunnel, installing one will also reduce the efficiency of the drying unit. Manufacturers are constantly striving to offer operators silencers that cut the noise without sacrificing drying capabilities.

Mac McElroy, CEO of Proto-Vest, Inc. in Glendale, AZ, says his company's silencers cut noise in all three areas of the dryer--the intake, the cover and the outlet.

"We are presently working on some additional silencing," McElroy says. "We can build a dryer with silencing in mind where the customer only hears the air coming out of the nozzles--you can't hear the motor at all. When you're designing a blower you have to be able to design the silencing package so that it doesn't take away from the performance of the dryer."

McElroy says Proto-Vest's silencer package reduces noise decibel levels on Proto-Vest dryers by 10 decibels--that's 10 times quieter than the unsilenced model.

There are other things an operator can do to reduce noise for employees and customers.

David VanBruggen, chief engineer for Superior Car Wash Systems, in Phoenix, AZ, says Superior's silencers are placed about 3 to 5 inches in front of the inlet. The silencers contain sound absorbing and sound dampening materials--the combination of which makes the silencers most effective, he says.

VanBruggen says there are a variety of factors that contribute to noise in a carwash tunnel.

"Obviously the more motors you have the more noise you tend to have," VanBruggen says. "There are so many things that happen in the wash that affect results when you're trying to deal with sound. Resonance off walls--anything of that nature can really impact how well something works or doesn't work."

For example, VanBruggen says block walls absorb more sound than metal walls. The proximity of the dryer to doors and walls can also make a difference in noise levels, he says.

"Having more enclosure to a dryer is helpful. Typically most dryers today are not really enclosed," VanBruggen says. "Sound dampening type material, accoustical tiles and baffles can also help contain sound in an area."

Dean Ducoing, inside sales support for Belanger, Inc., Northville, MI, says, "The farther inside the building you go (with the dryer) the more chance the noise has of being somewhat absorbed by the building," Ducoing says. "The problem is that most carwashes have cinder block walls, cement ceilings and all of them have cement floors. In that case you have all four surfaces that just bounce sound around."

Ducoing says he has seen some operators put sound dampening materials on the walls and hang panels in different areas of the carwash to absorb the sound. But Ducoing says these types of materials work best in larger tunnels since they are likely to get wet in smaller tunnels--becoming a harbor for bacteria.

Several years ago, carwash operators didn't face the noise concerns they face today, McElroy says.

"OSHA is starting to look more closely at the carwash industry," McElroy says. "It's becoming an issue when people try to put in a new installation. They're running into something we didn't see 10 years ago. Many operators are calling us to get our (dryer noise statistics) in order to get permits from the cities."

While noise pollution is a concern in all 50 states, nowhere is it taken more seriously than in California. McElroy says some California counties have dB requirements that are actually lower than OSHA requires.

"When we first started this, it seemed like California was far more prevalent (in noise control) than other areas," McElroy says. "We're running into more of that now in Florida, Arizona, Washington D.C. and Vermont."

How Loud is Loud?

The decibel (dB) is the smallest single unit of loudness. So how do dryers measure up in this loud world?