Blower Technology Keeps Advancing

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For landscapers looking to replace or upgrade their leaf blowers for the first time in several years, the first thing they’ll notice is that there are more lower-noise leaf blower options on the market. Most manufacturers offer commercial-grade leaf blower models with sound ratings at or below 65 dBA.

“There’s a standard for this — ANSI B175.2,” explains John Foster with STIHL. He encourages landscapers working in areas where sound levels are an issue to look for the sound level rating per the ANSI standard on blowers before buying. “There’s a voluntary by-stander labeling provision, and most manufacturers are now putting on their products what the sound level rating is based on that test procedure. So go to a manufacturers’ website and look up the specifications to see if it meets what you need. The 65-dBA sound rating isn’t necessary in all cases; in some wide open places where you need a lot of power, you may not be able to find quite as much performance in a lower-noise blower.”

A27958_1_fullFoster says a good approach for many landscape companies is to carry different blowers that can be used based on the power needed for a given job, the time of the day and year, and any local noise restrictions. “You probably should own at least one low-noise blower, just to reduce the potential for complaints in certain places, if nothing else,” he says.

A lot of engineering work has gone into developing quieter blowers. Larry Will, who led the design effort for the first quiet (65 dBA) blower at Echo 15 years ago, says he took a detailed approach to the issue, starting with a high-quality sound meter in a special sound room. He then took measurements of the different sound frequencies generated by a blower and set out to determine where those peak sound frequencies were coming from. “Is it a muffler? Is it an air cleaner? Is it an air leak or a vibration from a fin on the cooling fan on the engine? You have to look at all of the different sources,” Will explains. “Then you attack each source. If something is made of sheet metal, will changing it to plastic make it stop ‘singing?’ Will putting a little sliver of rubber between two parts dampen out that sound? You might add foam rubber in certain places or something inside the air cleaner to absorb sound. You work your way through the whole thing and that’s how you end up at your goal.”

Developments have continued over the years. “To achieve low noise on a modern blower, manufacturers typically look at using a combination of noise-deadening materials, as well as designing the plastic parts of the unit to help reduce engine, intake and blower fan noise,” explains John Powers, senior product manager at Echo.

Sometimes, additional design features are incorporated. STIHL, for example, uses special baffles in the tubes of some of its blowers to help reduce noise levels.

In terms of modern developments in blowers, the main areas of focus for most manufacturers (other than noise) has been increasing blower performance,” says Powers. “This has been achieved both through improvements in engine horsepower output, as well as blower fan efficiency, which allows manufacturers to get the most blower performance out of the available power from the engine. We have seen improvements in blower performance across nearly every type of model over the past five to seven years.”

The advancements are likely to keep coming. For instance, “cordless electric (battery) blowers are starting to become more readily available,” says Foster. While the run times on a charge can’t yet match those offered by commercial-level gasoline-powered blowers, “the performance levels when low-noise or zero-exhaust emissions are necessary are getting up there,” he explains. For lighter blowing jobs, such as clearing clippings from a sidewalk after mowing, a battery-powered blower can provide landscapers with an option. This is especially important since some cities, such as San Jose, California, are currently considering allowing only lower-noise electric leaf blowers. With advanced performance, Foster feels electric blowers will continue to grow in popularity over the next five years.