A Follow-Up To Determining Direction Of Sound

My previous post, Determining Direction of Sound During a Search received some very interesting comments, including a couple from Del Morris of the Sonoma County Sheriff's Search & Rescue / Helo Unit. Del wrote an article (2003) about the use of sound during searches:

 

WHISTLE STOP

The controlled use of sound during searches for a responsive subject is a stratagem that should be a practice of every SAR Team.

At a "Sound Sweep" exercise, we were debriefing our "victims" and our searchers, graphing/mapping the time and location of each "whistle blast" and the victim's perception of direction from where the sound was coming from. We discovered that the distance of sound travel and perception of sound direction was so variable that it deserved further study.

After some additional field testing and research in acoustics, I offer the following suggestions:

1] Shift to lower frequency whistles 2000-3000 Hz or fog horns (marine supply) Plastic horns(sports events) Compressed air horns (marine supply). The higher frequencies are “absorbed” by humidity and vegetation.

The lower frequencies will more readily bend around vegetation and rocks.

2] “Whistle Blasts” a.k.a. “Whistle Stops” can be done during the normal course of a Team Assignment whenever you are "inline" with a drainage *** Contact SAR Base and request a "WHISTLE STOP". SAR Comm. will then orchestrate a "Whistle Stop" by contacting all Teams, giving all teams time to get "inline" with other drainages, and doing a count down ( 3...2...1) to a great blast" just like during a "sound sweep" ...  followed by that all important listening period.

3] Teams that are on ridges will be at a disadvantage. Their whistles will be difficult for the subject to discern direction of the team. The subjects return whistle blows or yells for help will be equally difficult for the team to accurately determine the location of the subject.

4] Teams that are at the bottom (below the subject) of a drainage will a)have the best chance of hearing the subject in the drainage and b) have the most accurate direction of where the subject is. They will hear the subject better than the subject will hear them.

5] Teams that are at the top (above the subject) of a drainage will a)have the best chance of the subject in the drainage hearing them and b) have the second most accurate direction of where the subject is. The subject will hear them better than they will hear the subject.

6] Frequency is more important than additional decibels. 3 -110db whistles does not equal 330db. The combined decibel level is only about 117db. Sound level does not build exponentially. Some frequencies “blown” side by side can actually cancel each other do some degree.

DISTANCE was greatly increased with the lower frequencies of sound (yelling was heard a lot further than a whistle). The lower feqs are not gobbled up as readily by vegetation and the moisture in the air. I reference the use of low freqs in Fog Horns. Our “victims” all heard "yelling" before they heard a discernible "whistle" at a time when the "yelling" teams were further away. Whistles seemed to be blended with the crickets and other background noises.

DIRECTION or the perception of direction was more accurate when teams were "blowing" or yelling while inline with the drainage where the victim was. Blows that were blown by teams that were on the sides of hills or tops of ridges ... the victims found the sound very difficult discerning from "forest" noise and on the whole non-directional.

Sound seems to carry better up hill than down hill, better with the wind than against.

WHISTLE STOP can be used during any "phase" of a search for a responsive subject. Hasty teams running trails, dog teams doing area searches, etc. ... WHISTLE STOP is a more effective use of person power.
A comparison could be made between "closed grid" search lines (Sound Sweep) and "open grid" purposeful wandering (WHISTLE STOP) searching methods.

Del Morris
Sonoma County (CA) SAR Unit

Fraudulent Organization Takes Over SAR Site

I recently received an email from a former trainer from a now-defunct Ohio K9 team, who'd noticed a link to their website on my SARStories K9 Team Directory.  She wrote:

"I just wanted to inform you that Ohio K9 Search Team officially chose to cease operations in 2008. ... The web page to which you are linked is a fraudulent site sponsored by some Russian group.  We discovered that, after we closed our website, this Russian group took it over and is fraudulently collecting money by using our name.  ...  We former K9 team members have contacted the Russian group and asked them to stop using our name and our photographs, but since the [Ohio] team no longer officially exists, there is nothing we can do about it."

The former team member went on to say that they reported this fraud to the Better Business Bureau, various police agencies, and the Ohio Attorney General's office, but they were told there is nothing anyone can do to make this Russian organization stop using their name or photographs.

She explained, "Apparently, there are organizations that search for domain names that are not being renewed and they take over the websites.  We notified the internet server holding the domain name that we would not be renewing, but our photographs and other information did not get deleted on one of our websites.  So, the fraud-based organization took over the site and added a link for people to donate money. ... When we existed, our team was never linked with any person or group from another country.  We also never collected money over the internet.  Unfortunately, since the rogue group paid for our domain name, they can do whatever they want with it, and we have no control or say in the matter."

There is also concern about this fraudulent group meeting with potential volunteers.  A contact from a local park called to ask if the K9 team was supposed to be training there.  Apparently, a woman sent an email to the web site, inquiring about the group, and she was invited to a training session.  When she arrived, the only vehicle around was an old van with two "suspicious-looking men" inside.  Concerned, the woman then went to the park office.

The former team member tells me the group that has taken over the website has ignored attempts to contact them.

What do you think about this situation? It certainly seems to me that something should be able to be done about this.

See the "Official Ohio K9 Search Team, Inc." site at http://www.ohiok9.org/.  Note the comment about Russian organizations on the bottom of the first page, in very small, gray print.

Featured Site: Search and Rescue Knowledge Exchange

I recently started participating on a site developed by Ian "Splash" Turner, a member of S.A.R.A.I.D. (Search And Rescue Assistance In Disasters), a British organization "dedicated to trying to save the lives of innocent victims of disaster, as well as relieving human suffering around the world regardless of color, creed, religion and political persuasion." (Members of S.A.R.A.I.D. have been deployed to Haiti in the aftermath of the earthquake. You can read their updates on their blog, S.A.R.A.I.D. News, and via their posts on Twitter.)

Ian's website, Search and Rescue Knowledge Exchange, is a place for anyone, whether involved with SAR or not, to ask SAR-related questions and, if able, to provide answers to those questions. As the FAQ says, "No question is too trivial or too 'newbie.'" Questions may also pertain to gear and book reviews and backcountry skills.

Some of the recent questions and topics have included:

• How do you get involved with Search and Rescue?
• How to deal with the problems of timing and team member attendance at a debrief following a mission
• Filtering water in the outdoors
• What is the best way to manage team training records?
• The best way to sleep rough
• What is the right amount of medical training for a SAR participant?
  

Visit Search & Rescue Knowledge Exchange to browse questions and answers and jump in if you'd like. You can even ask and answer your own question, and multiple answers are permitted and encouraged for each question. Answers may include links to outside sources and/or to other Q&A threads on the site.

You don't have to register to participate—to ask and answer—but there are additional features available to those who do register with an OpenID account.

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And here are some recent SAR articles...

Wayward Berthoud Pass beacon a problem for search and rescue teams: "A wilderness rescue device designed as a "just in case" safety lifeline has developed into a recurrent nuisance. ... A string of eight false alarms in the past month has renewed debate over the controversial personal locator beacons (PLBs) and leaves local rescue experts frustrated over a lack of backcountry education in the technological era."


UK Search and Rescue Teams Saving Lives in Haiti: "Search and Rescue teams from the UK are among the first to travel to the devastated town of Leogane to continue their search for survivors of the Haiti earthquake."

FDNY-NYPD team in amazing three-hour rescue of man trapped under layers of concrete: "It took three hours to cut through the rebar and cement blocks and dig a narrow crawlspace into the pile of rubble where the apartment building once stood."

No Way Up Or Down: "Documents describing last summer's massive search [in Grand Canyon] for Bryce Gillies show he was on the brink of Thunder River that may have been just out of sight when he returned to the next drainage, where he went down a series of steep pour-offs."

Some Interesting SAR Articles

For those of you on the SAR-L email list and/or the Search & Rescue Discussion Group on LinkedIn, you may already have seen most or all of these. But here are some articles from the world of SAR I've read lately that I found interesting:

Spot + GPS = new device introduced at the Consumer Electronics Show: (pictured here) "Unlike the traditional Spot device, the Earthmate PN-60W will allow the user to transmit custom messages, which can be sent to your emergency contacts as well as your Twitter and Facebook friends." (And Search & Rescue)

Police Train Vultures To Find Human Remains: "German police are testing the use of vultures to seek out human corpses in a unique project aimed at dramatically speeding up criminal investigations."

GPS Leads 3 Parties Astray in Oregon: "In a holiday hurry, Jeramie Griffin piled his family into the car and asked his new GPS for the quickest way from his home in the Willamette Valley across the Cascade Range."

Editorial: Personal Responsibility Seems Missing Among Hunters Stranded By Storm: "How do you prevent people from putting themselves in so much danger of death or injury that someone else has to come rescue them? Should they be charged for the rescue? Should they be fined if it turns out they were breaking a rule or regulation? Should they be barred from returning to, say, a national park where they were rescued?"

Boy Escapes Death Despite 16 Hours In Freezing Cold: "In an amazing story of survival a 13-year-old boy survived more than 16 hours in the freezing cold California mountains without shoes."

Searching With Compassion, Surviving With Grace: "If you're looking for courage, dignity and faith this holiday season, it's in plain sight with search-and-rescue teams and the loved ones of the lost."

Find any interesting SAR articles lately? Let me know, and I'll add them to my SARStoriesNews posts, including who submitted them (with a link to your SAR or team site if applicable).

Determining Direction of Sound During A Search

I recently received an email from a young woman who, along with her hiking partner, was rescued by SAR volunteers after getting lost in the mountains of northern California's Angelo Coast Range Reserve. According to the woman's account, searchers were fairly close all night, yet despite having voice contact with the subjects, they weren't able to locate them until morning.

As the two women huddled together for warmth in the intermittent rain, they periodically saw the SAR team's lights and heard their shouts, though they couldn't make out their words (or vice versa, apparently). Without a light source of their own other than the small screen of a cellphone, which they didn't try to use for signaling, the ladies had no way to indicate their location other than to shout back at searchers.

With what little battery power she had left on the phone, one of the lost hikers made calls to 911 in an attempt to have the dispatcher relay to the searchers where the subjects were in relation to the team's lights and shouts. Eventually, the cellphone went dead, and the shouting continued. Searchers were having a lot of difficulty determining the direction of the subjects' voices in that mountainous terrain.

Having had similar experiences during SAR missions, when it was difficult to pinpoint a subject's location despite being within hearing range, I thought I'd look into the fickleness of sound and how we as searchers can better hone in on the source of that sound without the aid of a visible light source. I didn't find a whole lot.

First, I read an article called The Direction of Sound, which explains the interplay between time lag, wavelength, and tone. This all makes perfect sense, but it's not always so easy in practice.

Then, in another article I came across about auditory perception, the writer states that a listener can acquire more information about the direction of a sound by moving their head, adjusting the orientation until the source of the sound seems to be located out front, where a human's localization sensitivity is greatest. 

So, if searchers stop moving and take time to call back and forth with the subject, turning our heads as we listen to each call, this would be better than continuing to move while exchanging shouts or whistle blows with the person/s we're trying to locate.

I also found an electronic device, a "bionic" ear with a booster dish, which is said to increase sound by up to 40 decibels and apparently is highly directional, allowing the user to locate the source of a sound. Search and rescue is listed as one of its intended uses; however, I've been unable as of yet to find any comments or reviews by a SAR team that's used this technology.

During one search I was on in the company of a SAR K-9, the handler closely watched his dog's ears each time we heard a shout somewhere in the distance. Just as the dog heard the sound, her ears would twitch in a particular direction. Her handler told me this was a very good indication of the direction the sound was coming from.

If anyone has any additional suggestions or feedback on what little I've discovered so far, please leave a comment. 

Featured Team: SAR Dogs Nepal

I first became aware of this search and rescue team when I corresponded with their founder and Managing Director on LinkedIn and decided to learn more about them.

SAR Dogs Nepal (formerly known as the Himalaya Rescue Dog Squad), established in October 1989, by Dutchman Ingo Schnabel, is the only organization of its kind in the country, providing search and rescue teams and medical aid in the event of natural disasters and when trekkers are reported missing or injured. The squad is able to provide air rescue and tracker dogs to almost any area of Nepal. Members are experienced in a wide range of disciplines, including rock rescue, firefighting, logistics, and wilderness medicine.

The team has a newly formed Junior Rescue Squad,  thanks in large part to American dog trainer Lynn Martin from Oregon's Dog Obedience Academy, who traveled to Nepal with her sister, Kathleen Reick, to help SAR Dogs Nepal train six newly recruited Nepalese youngsters.  This follows a hiatus during The People's War in Nepal from 1996 until 2006, when SAR Dogs Nepal could not continue its training of new disaster relief workers. At present, only 18 staff members and 9 Nepalese volunteers remain, while the team's goal is to have a minimum of 100 disaster relief workers on standby in their mobile  Disaster Relief & Medical Aid Unit.

The team's main headquarters, including a dog breeding and training center, is in Shyauli Bazaar, Lamjung District, in the center of Nepal. They often work at an altitude of  5600 meters (18,373 feet) or more, in diverse and often harsh conditions--from jungle gorges to flooded plains, avalanche zones, and even large-scale traffic accidents.

Flash flooding is common in Nepal, when the monsoons bring heavy rain and heat, melting snow and ice to the rivers. There's also a lot of seismic activity, making landslides, earth tremors, and even full-scale earthquakes constant threats.

Due to a lack of national infrastructure and government support in the field, SAR Dogs Nepal has provided the only medical disaster relief to poor villages in remote areas.

You can learn more about the SAR Dogs Nepal and about the country on the team's website at SARDogsNepal.asia

Youth In SAR

I used to think you had to be 18 in order to participate in search and rescue. But now I know that assumption was wrong. In fact, there are whole teams made up of youth volunteers.

Take Long Beach Search & Rescue, for example. From their website:

Long Beach Search & Rescue "provides young adults with an opportunity to serve the public during emergency situations while encouraging them to explore career possibilities in the law enforcement, fire protection and emergency medical services fields. Long Beach Search & Rescue is an award-winning Learning for Life Explorer Post co-sponsored by the Long Beach Police Motor Patrol and Long Beach Firefighter's Associations." All applicants must be between the ages of 15 and 18 and maintain at least a C grade point average in school, among other requirements.

There's also Explorer Post 2002, a youth Search and Rescue team sponsored by the Sonoma County, California, Sheriff's Department. After finding this team, I then did a search for Explorer Search And Rescue (ESAR) and found youth SAR teams all over the country, including but not limited to Arkansas ESAR, Washington ESAR, and King County ESAR, the first youth-based search and rescue team in the nation, established in 1954.

Some states, such as New York, don't accept SAR applicants who are under 18 years of age. However, organizations such as Boy Scouts of America and Civil Air Patrol do have units around the country that have Search and Rescue training tracks that minors can get involved with. Explorer Search and Rescue (ESAR) teams are made up of teens--boys and girls--in the Learning for Life program, a subsidiary of the Boy Scouts of America, who are trained and deployed for search and rescue missions. 

Here are news stories about two young and accomplished SAR volunteers:

Arizona Teen and her Search Dog Pass National Certification: After completing her ground searcher certification, 16-year-old Taylor Lane of Sonoran Search & Rescue submitted an application to the Paws of Life Foundation's program to pair canine handlers with dogs. Lane and her search and rescue dog recently passed NASAR's Canine Sartech I evaluation.

To the Rescue! A young search-and-rescue-volunteer comes to the aid of lost or injured hikers in northern California: Now 18, Tamsen Bell started with Marin Search & Rescue when she was 14 years old, the youngest age at which one can join. When Bell was 16 years old, she took a lead role in a SAR mission involving a 60-year-old hiker who fell 50 feet off a cliff and landed on a mountain ledge, breaking part of her neck and suffering other injuries. Bell then slid down a steep part of the mountain to get to where the injured woman lay. She then examined the victim to find out what kinds of injuries she had suffered and decided the best way to transport her to safety.