MSW Management | Ahhhh … the Peaceful Sounds of Garbage Trucks

SUBSCRIBE

COMMENT
ON THIS
ARTICLE

CREATE A LINK
TO THIS ARTICLE
ON YOUR SITE

Wheeeeeeee! Wham! Sounds not long for this world

By Nikki Stiles

With horns blowing, music blaring, and engines roaring, it’s no wonder New York City is “the city that never sleeps.” However some residents are seeking relief from the noisy hustle and bustle of city life. In December 2005, the city passed a new noise code, which was the first revision in 30 years. This all-encompassing code addresses noises produced by everything from construction, jackhammers, and musical devices to garbage trucks. Many other cities are addressing noise issues with garbage trucks as well. And manufacturers are following suit by producing collection vehicles that are easier on the ears.

New York City’s Noise Code
To alleviate some of the city’s noise, New York City’s new noise code sets decibel levels and equipment standards for garbage trucks with compactors. The code states that no compactors may exceed 78 decibels when measured from 23 feet away while running but not compacting. The code also prohibits operation of garbage trucks and compactors within 50 feet of residential property after 11 p.m. and before 7 a.m. if the aggregate sound exceeds 85 decibels when measured 35 feet from the vehicle. After July 1, 2009, the decibel level could be reduced to 80, depending on technology, but by July 1, 2012, garbage trucks and compactors must comply with the 80-decibel level.

Violators of garbage truck noise rules may be slapped with fines ranging from $440 to $1,400 on the first offense, $880 to $2,800 on the second offense, and $1,320 to $4,200 on the third and subsequent violations.

Larry Stone, New York City account manager for Heil Environmental Industries Ltd., deals with the new noise-code issues firsthand. “The law addresses everything,” says Stone. “They won’t allow a truck with a jake brake. That’s a braking system that uses engine compression to slow down the truck. When the compressed air in the engine cylinders is released, the truck slows down, but it also makes a very loud chattering noise.”

To help address some of these noise issues, the company now uses operate-at-idle vehicles in New York City. An operate-at-idle system enables a vehicle to load and compact garbage at standard operating speeds while the vehicle engine is idle. Normally, operators driving vehicles without an operate-at-idle system have to shift the transmission into neutral and raise the throttle (rev the engine) every time they want to lift a container or pack a load. All of this shifting and engine revving creates additional noise. Another added bonus of operate-at-idle vehicles is a reported 20% decrease in fuel consumption.

“Most of the noise obviously comes from when the engine revs. The engine needs to rev when the body is packing. That’s traditionally what happens with a garbage truck,” says Tom Vatter, vice president of sales and marketing for Hagerstown, IN–based Autocar LLC. “With an operate-at-idle garbage truck, they put a hydraulic system on the body so the truck doesn’t need to rev up. The hydraulic system is capable of packing and keeping those pressures without revving the rpms of the engine, which obviously creates noise.”

The City of Abilene, TX, solid waste department has used operate-at-idle vehicles for several years now. The city has 16 collection vehicles, 13 automated side-loaders, and three front-loaders that are all equipped with operate-at-idle systems, and 12 other trucks that are not. “It saves fuel and wear and tear on the transmission, and the engine is a lot less noisy,” says Mike Wegner, solid waste manager for the city of 116,000. “We have a downtown area that has residences in it, and one of the reasons we have operate-at-idle on the front-loaders is for it to be quieter, because we have to go in early in order to get through before the traffic starts.” Wegner says the operate-at-idle collection vehicles consume 15%–20% less fuel compared with traditional vehicles. Operate-at-idle vehicles save fuel by using a larger hydraulic pump that produces the extra flow of fluid needed for a collection vehicle to load and compact garbage at standard speeds while the engine remains at idle.

EPA Emissions
Stone says the new EPA emissions requirements also pose some challenges when it comes to collection vehicles. The “2007 Highway Rule” requires that pollution be reduced from heavy-duty highway vehicles by 90%. Beginning with the 2007 model year, the EPA requires a 97% reduction in the sulfur content of highway diesel fuel from its current level of 500 ppm (low-sulfur diesel, or LSD) to 15 ppm (ultra-low-sulfur diesel, or ULSD). Refiners began producing cleaner-burning diesel fuel, ULSD, for use in highway vehicles in June 2006.

To help meet these emissions requirements, Stone says manufacturers have added diesel particulate filters, which make the engines run hotter. “On a garbage truck the noisiest component is the engine fan, and the second-noisiest component is the hydraulic pump.”

Stone says the operate-at-idle system helps alleviate the hydraulic-pump noise simply because there is no need to throttle up. The engine fan, however, is another story. “The engine noise is probably going to get worse before it gets better due to the new 2007 engines and the fact that these engines are running hotter than they were in the past. Truck manufacturers are looking for additional ways to keep these engines running cooler. One of the things that one manufacturer has done is increase the number of blades on the engine fan and change the pitch of the engine fan.” This might help with emissions, but Stone speculates that the engine-fan noise may get louder as a result of these changes.

Nighttime Trash Pickup
Another reason quieter collection vehicles are needed is that some of the larger cities are now having trash pickup in the evening and at night. Jersey City, NJ, announced in December 2006 that it would have residential trash pickup and recycling during evening hours. To follow through with this task, the city will use operate-at-idle collection vehicles.

The city hopes to alleviate some of the daily traffic congestion by switching to evening hours. The mayor of the city, Jerramiah Healy, feels that having evening trash pickup will help with street-sweeping services—since in some areas the street sweeper arrives before the garbage trucks in the morning—and reduce the amount of litter caused by night scavengers.

Also, the city hopes that having garbage trucks on the streets at night will act as a deterrent for criminals. “This new initiative is advantageous to Jersey City in many ways,” the mayor says. “Traffic congestion and pollution will be reduced, and night collection may serve as a deterrent for illegal activity or crime. With the amount of growth and development in a city of our size, night trash and recycling collection is vital to enhancing the quality of life of all those who live and work here.”

“We are at a point where it is no longer a choice but a vital necessity that the trash and recycling be picked up during the evening hours, when the vast majority of the general public is off the streets,” says Oren K. Dabney Sr., chief executive officer of the Jersey City Incinerator Authority. “Jersey City is joining West New York, Union City, Guttenberg, and Hoboken—which already employ evening trash collection in their quest for safer streets and cleaner cities.”

Diesel Versus Natural Gas
Another way collection vehicles may reduce noise levels is by employing natural gas instead of diesel, according to an investigative report conducted by Inform Inc., a national environmental nonprofit research organization. The report says that natural-gas engines are spark-ignited rather than compression-ignited, which allows them to operate at much lower compression ratios thus resulting in quieter engines.

Inform found that of the 179,000 waste-collection, waste-transfer, and recycling vehicles on the road today in the United States, 91% are diesel-fueled. The garbage truck sector alone is responsible for consuming approximately 1 billion gallons of diesel fuel annually, representing nearly 3% of total diesel fuel consumed in the United States.

Diesel garbage trucks can generate noise levels up to 100 decibels. A study in the Netherlands found there were noise reductions with natural-gas vehicles of 90% inside the truck, 98% beside the truck, and 50% behind the truck when compared to a diesel-powered vehicle.

Going Greener
Maybe not so much to reduce noise but to become “greener” environmentally, some areas are converting from diesel fuel to natural gas. Southern California now requires garbage trucks and transit buses to use cleaner-burning alternative fuels. Houston-based Waste Management Inc. now operates 13 natural gas–powered fleets in California, with a total of 400 Cummins L10G dedicated natural gas–engine garbage trucks.

On January 2, 2007, Smithtown became the first municipality in New York state to require contracted garbage centers to use only vehicles that run on compressed natural gas (CNG). The town is now using 22 CNG garbage-collection vehicles in hopes of improving the environment, reducing dependence on foreign oil, and having quieter vehicles.

Stone says his company supplied nine CNG vehicles to the town. “All CNG trucks I’ve been around have been no noisier than a diesel, and most of them have been quieter,” he says. So far only one resident in Smithtown has complained to the city about the new collection vehicles. “One guy said he used to use the old trucks as his alarm clock to get up for work, and now these are so quiet that he has been late for work,” Stone says.

Costs of Going Greener
Although more manufacturers are offering operate-at-idle collection vehicles for their customers, the move toward natural gas–powered collection vehicles is still at a lull. According to the Inform report, in the past four years the number of natural-gas vehicles in the United States has doubled to 700. While this is encouraging, considering that there are 179,000 collection vehicles in operation, there is still room for improvement. Some of the reasons for this may be due to the cost and availability of natural gas. On average, a natural-gas garbage truck costs $40,000 more than a conventional diesel-powered truck. Refurbishing a conventional diesel truck to operate on natural gas by replacing the engine and fuel system can cost anywhere from $30,000 to $100,000. When fueling takes place onsite, there are additional costs associated with the installation of natural-gas fueling infrastructure. “Most garbage trucks are diesel-powered due to the limited availability of natural gas. It’s just not available everywhere,” Stone says.

To accommodate Smithtown, the New York State Office of General Services recently completed an upgrade to the compressed natural gas fueling station adjacent to the Perry B. Duryea Jr. State Office Building in Hauppauge, NY. The station’s upgrade expands the CNG dispensing capabilities to approximately 1,000 gallons per hour and adds two additional dual-hose dispensers. These upgrades make it the largest publicly accessible CNG fueling station on the East Coast.

In many areas there are grants and tax incentives to offset these capital costs. Public funds are available from federal, state, and local policymakers in California, New York, and other states to help the switch to alternative fuels. According to the Inform report, operators that introduce natural-gas trucks into their fleets may also be able to generate mobile-source emission reduction credits (MSERCs). These are awarded for low-emission–vehicle projects that go beyond the requirements of current government standards. Reducing garbage truck emissions could result in marketable MSERCs for refuse-collection companies. The South Coast Air Quality Management District permits the trading of MSERCs in Southern California, and this practice could be applicable elsewhere.

Occupational Noise Hazards
Not only is noise from collection vehicles a nuisance to residents in neighborhoods, but it is also an occupational hazard for those who operate and ride along in the vehicles. The standards set by OSHA permit employees to be exposed to 90 decibels for up to eight hours, a level that diesel trucks come close to or exceed.

The study in the Netherlands found that, with natural-gas trucks, noise levels experienced by drivers dropped by more than 90% (from 82.8 to 71.3 decibels). Levels experienced by workers standing beside the trucks decreased by 98% (from 79.5 to 69.3 decibels), while levels experienced by workers behind the trucks dropped more than 50%.

Richard Ball, marketing director for Ladson, SC–based American LaFrance, says his company does not produce operate-at-idle vehicles or natural gas–powered vehicles; instead it is focusing on occupational noise hazards for the drivers of its vehicles.

“Most of your noise issues of waking somebody up in the morning have to do with front-loaders; they pick up those big cans, dump them, and slam them down. It’s like a bomb going off,” Ball says. “For a chassis manufacturer, there’s not really much we can do—it’s more on the operator and how they operate the equipment. So I don’t think the operate-at-idle helps much on that side.

“Our biggest complaint that we have now is from the driver’s side. With our 2008 model that begins production in May, we will have new insulation for the tunnel where the engine goes to reduce the noise the driver would hear all day from the engine.”

Cushioning the Noise
While operate-at-idle systems and natural-gas vehicles may help reduce engine noise, there are other components on collection vehicles that produce noise as well. Front-loaders, for instance, which typically empty large garbage bins, are noisy by nature. Some noise can be reduced by a skilled operator, but certainly not all.

“Unfortunately, front-loaders are just noisy by nature. You’re taking a container high up into the air and then letting material fall out of that container into the truck, and that makes noise. And the lid closes when you come back down, and that makes noise. If you are trying to empty a container at a fast-food restaurant where there is an enclosure, you might have to pull the container out of there, and that makes noise,” Stone says.

Stone says his company has added features to help reduce some of this noise. “Our cylinders are cushioned internally both up and down,” he explains. “So as you are going up, the cylinders come to a gradual stop against the body, and we have some rubber pads that these arms rest upon. And we have the same thing coming down: We have cushions in the downside of the cylinder so it slows that assembly down as you get closer and closer to the ground, and what that prevents you from doing is banging your container into the ground—which besides making noise damages your containers.”

Sometimes Noise Is Inevitable
Many people enjoy waking up to the smell of coffee or the chirping of birds rather than the sudden startle from slumber provided by a noisy garbage truck. That is one point most everyone can agree upon. But considering the average American throws away 3.5 pounds of garbage a day, collection vehicles are definitely a necessary part of life and sometimes noise just comes with the territory.

No matter what kind of collection vehicles are used or how they are fueled, when large, heavy containers of trash are being emptied into a truck, sometimes there is just no tiptoeing about it. Noise is an occasional part of life, but, if we can turn down the volume a bit, then why not?

Based in the city of Fairmont, WV, Nikki Stiles writes on subjects related to technology.

MSW - May/June 2007