At Sandy Beach, the "Dangerous Shorebreak" signs sticking out of the sand never come down.

"Because over here, it’s always dangerous," lifeguard Aka Tamashiro said as he scanned the famous sandy shore below Koko Crater.

Indeed, Sandy Beach — renowned for its powerful waves and expert bodysurfing and bodyboarding — continues to be among Hawaii’s most dangerous beaches, as reflected by the latest data from the state Department of Health on spinal cord injuries.

There were 16 spinal cord injuries at Sandy during the five-year period from 2009 to 2013, which places the beach at No. 3 in Hawaii for such injuries.

Hawaii’s most dangerous beach?

Makena, or Big Beach, on Maui, with 22 injuries during that period. No. 2 is Hapuna on Hawaii island with 18.

Brennecke’s on Kauai is No. 4 with 15 injuries, while Kona’s Laaloa Beach, which is also called White Sands Beach or Magic Sands, rounds out the top five with 12 injuries.

Water safety officials say these beaches share certain similarities that make them prone to injury: They’re all exposed to open ocean swells that approach rapidly from deep water to shore, and the waves crash either directly on the sand or in very shallow water.

They are all gorgeous beaches that lure unsuspecting tourists by the boatload.

While auto accidents are the leading cause of neck and back injuries on the mainland (followed by falls and then gunshot and knife wounds), the leading culprit here is ocean activities, according to the Health Department — and more specifically from bodysurfing, bodyboarding, being tossed by a wave and diving into the water.

Your typical victim is a mature male tourist. Eighty-four percent of victims are male, 78 percent are nonresidents and 64 percent were between age 45 and 70, according to an analysis by Dan Galanis, epidemiologist with the state Health Department.

And while these dangerous beaches get their share of big and intimidating surf, the worst days often are when the surf is small and the danger isn’t necessarily apparent, officials say.

"It’s completely counter-intuitive," said Honolulu Ocean Safety Chief Jim Howe. "The concept that the small waves can’t hurt you: not true."

Dr. Monty Downs, a Kauai emergency room physician and president of the Kauai Lifeguard Association, described what’s happening at Brennecke’s: The local bodysurfers and bodyboarders "shoot the curl," riding sideways along a wave as it’s peeling and breaking, while new-to-the-ocean folks tend to just hop aboard a wave and surf straight in.

"And therein lies the problem," Downs said. "The bottom is quite shallow, 3 to 5 feet (and can get shallower) as water sucks out before a wave breaks. The wave can face-first you into the sandy bottom and they end up with a bad c-spine injury, as well as facial cuts or bruises or both." The cervical vertebrae are the seven bones in the neck.

Downs said the most dangerous conditions at Brennecke’s occur on the days when the waves have only 3- to 5-foot faces — dangerous because they’re not too intimidating for people to venture into, but big enough and powerful enough to cause damage.

"It can get big and ‘bombing’ and that’s for locals only — and it can be a fabulous wave — and ironically we tend to not see injuries in those conditions since the inexperienced will instinctively not feel safe heading into the water," he said.

Howe said those used to mainland waves don’t realize how much power the surf packs in Hawaii. On the mainland, the continental shelf creates drag and slows waves down, he said. In Florida, for example, waves travel at 12 to 15 mph, while in California the waves come in at 20 to 22 mph, he said.

In Hawaii, the waves crash into the islands at a full 35 mph.

"There’s nothing to slow them down, and that translates into energy," he said.

Howe and other ocean safety experts urged locals and visitors to learn as much as possible about the conditions they face before coming to the beach. One good way is to log into hawaiibeachsafety.com, established in cooperation with all of the ocean safety departments in Hawaii.

On one day late last week, the Williams family — mom, dad and two youngsters — new Oahu residents, ventured onto Sandy Beach but decided to leave less than a half hour later.

Informed by a reporter that Sandy’s is one of Hawaii’s most dangerous beaches, Amber Williams replied: "We just realized that. That’s why we’re leaving."

She added that they planned to drive up the road in search of calmer waters.

Army 1st Lt. LaRue Sutton from Mississippi, another new Hawaii resident, was relaxing on the sand with a visitor from the mainland.

"The first time I came out here, I got thrashed around," Sutton said. "I came out of the water with a sore back."

Although he returned to Sandy Beach, Sutton said this time he was being more cautious. He added that he’s learning you can’t underestimate the waves in Hawaii.

Tamashiro, the lifeguard, said you don’t have to be a tourist to get into trouble at Sandy Beach. He himself has been injured on numerous occasions, on the job and on his own time, going back to when he was at Roosevelt High School.

"I’ve been thrown on my head. I’ve had no use of my left shoulder for three weeks, no use of my right shoulder for a month and a half — all from getting pounded over here.

"Everyone gets hurt at Sandy’s. The ocean does not discriminate over here."

He said he tries to emphasize that point to visitors.

"What we generally tell the public is that the ocean over here wants nothing more than to throw your head in the sand. If you try to catch yourself, you get your shoulder and collarbone injuries. If it happens so fast you can’t get your hands up and it throws you on your head, that’s when your neck or back is going to go out. The sand never loses at Sandy Beach."

No. 1: Big Beach

Big Beach is a beautiful, golden-sand beach that is part of Makena State Beach Park in South Maui. Once remote, it has now gained in popularity, especially after the state established paved parking lots and put in amenities. Both residents and tourists alike make the trek to play in its clear waters and enjoy a spacious beach that stretches close to two-thirds of a mile long.

But the shorebreak can be unforgiving during a large south swell. Conditions are ideal for skim boarders and expert bodysurfers and boogie boarders but they can be downright dangerous, especially for those unfamiliar with its power.

With state funding, Maui County lifeguards started staffing the beach in 2009. Even so, Makena has led the state in spinal cord injuries three years in a row, from 2011 to 2013.

Cary Kayama, Maui County Ocean Safety supervisor, said lifeguards try to be proactive in warning about the dangers in the surf. Lifeguards use a public address system and patrol the beach, offering advice and sometimes suggesting that families with small children try another beach.

A Minnesota man posted this message on TripAdvisor: "It seems like every time I have gone there, I’ve seen someone hurt. Last year we did a quick stop just so I could show the beach to my aunt and uncle who were with us. A guy came out with a huge gash on his head."

No. 2: Hapuna

In 1993, Florida International University professor Stephen Leatherman, or "Dr. Beach," named Hapuna the best beach in America, calling it "a perfect place to swim, snorkel or scuba dive in the crystal clear waters."

But Hapuna — a wide, white-sand beach in South Kohala — has a habit of rising up and throwing people into the sand. Tourists flock here unaware of the surf’s powerful potential.

"Even experienced guys can get driven straight down into the sand," said Gerald Kosaki, the Hawaii island battalion chief responsible for overseeing the county’s 51 lifeguards.

The Hapuna State Recreation Area Beach website describes the surf this way: "Dangerous rip currents and pounding shore breaks during periods of high surf! Waves over 3 feet high are for experts — all others should stay out of the water and away from the shoreline!"

Surprisingly, some of the worst injuries happen when waves are small, Kosaki said. Some people dive over the waves and hit their head on the sandbar.

Kosaki said that in late 2013 the Hapuna lifeguards were finally equipped with a public address system.

Will it help?

"Only time will tell," he said. "Hopefully, we’ll see the figures drop."

No. 3: Sandy

The potential for injury at Sandy Beach Park is notorious. But it’s also the next beach on Kalanianaole Highway after Hanauma Bay. As soon as the Hanauma parking lot is filled, tourists drive up to Sandy.

Tamashiro said he and his fellow lifeguards suggest to novices and families with children that they keep driving down the road to Waimanalo Beach Park, where generally the surf isn’t so strong.

Howe said he’s proud of the efforts made to improve safety at Oahu’s beaches — and especially at Sandy. Over the past 15 years or so, the lifeguard towers were repositioned, a public address system was installed, more signs were employed and lifeguards were instructed to be more proactive, reaching out to beachgoers about the potential dangers they face.

If someone shows up without fins, Howe said, they don’t really belong in the surf there.

Tamashiro said he’s surprised only 16 injuries were recorded over five years.

"That’s awesome, because we’ve wrapped up way more than 16 people," he said. "Anytime we see any accident that might involve head or back injury … we stabilize the neck and get the ambulance here.

"The last thing we want is for someone to go to the hospital. It’s a beautiful weekend and everybody’s having a great time and then all of a sudden it possibly could be the last time that person walks."

No. 4: Brennecke’s

Downs, the ER doctor, said those in the emergency room call the beach "Breakneckie’s."

"Not funny, though," he said.

The beach is named after Dr. Richard Brennecke, whose house at that spot washed away in Hurricane Iniki in 1993. It lies in the heart of Poipu, with multiple hotels and time shares nearby. The Poipu lifeguard tower is about 200 yards away, around a point, and the beach is actually obscured from its view.

There won’t be any injuries for a while, however. The tropical storms that pushed by Hawaii last summer took away all the sand.

When it is a beach, it’s a perfect bodysurfing and boogie-boarding sandy-bottom beach, Downs said. It is less than a football field long and can get crowded with well over 100 people and their bodyboards.

No. 5: Laaloa

This is another beach where sands get carried away by large swells. This can happen as fast as a 24-hour period, which is why this Kona beach is also called Magic Sands or Disappearing Sands.

Like the other beaches on this list, a strong surf break makes it dangerous, but it also makes it a favorite for bodyboarding by experienced locals.

A Utah man wrote on TripAdvisor recently: "The rip tide and waves are very strong, which is why we went in the first place because we wanted to boogie board. What I wasn’t expecting was to break my arm after getting caught in a huge wave and getting driven into the sand. Upon getting to the ER, when I told the nurses that the injury occurred at Magic Sands, they proceeded to tell me that the nickname they had for the beach is ‘Tragic Slams’ because of the number of injuries they see go through that ER. They told me I was lucky I didn’t break my neck or get a very life-threatening injury."

A Canadian visitor added: "The ambulance was there quite often during our almost three-week visit. A young boy suffered a spinal cord injury one day and had to be worked on for several minutes by ambulance attendants to get him breathing again. I was knocked down in knee deep water and pummeled by a wave which ripped my prescription sunglasses right off my face … It is a fun beach when the surf is tame, but keep a sharp eye on your children and never turn your back on the waves for a second."