(CNN) Though it has been a divisive addition to Formula One cars this season, the "halo" proved its worth on Sunday during a spectacular opening-corner crash at the Belgian Grand Prix.
When Fernando Alonso's car was sent airborne after a shunt from Nico Hülkenberg, the halo on Charles Leclerc's cockpit deflected the impact of the Spaniard's McLaren.
The titanium structure, built around the cockpit to protect drivers' heads, sustained severe damage and left many wondering how bad the outcome could have been had it not been there.
Its addition to the sport, which was not without controversy, is just one of a multitude of changes introduced to F1 over the past decades to make the sport safer.
And some of those changes have come as a result of tragic accidents on the track.
READ: Formula One's "halo" device proves worth at Belgian Grand Prix
READ: Sebastian Vettel wins Belgian GP after avoiding huge opening corner crash
Ayrton Senna and Roland Ratzenberger, San Marino 1994
Security personnel surround the crashed car of Brazilian Formula One driver Ayrton Senna.
Arguably the most high-profile crash in F1 history, Ayrton Senna's death at the 1994 San Marino Grand Prix -- just a day after Roland Ratzenberger was killed during qualifying -- brought about some of the most sweeping changes seen in the sport.
A three-time world champion at the time of his death, Senna is still widely considered one of the greatest F1 drivers in history.
There were reports that the Brazilian was left so shaken by Ratzenberger's death that he was contemplating whether he would even race in the following day's grand prix.
Story of the F1 season
Lewis Hamilton sprays second-placed Sebastian Vettel with champagne after winning the Abu Dhabi season-ending race, 11th of his title winning season.
Lewis Hamilton celebrates his 10th win of the season as he takes the Brazilian GP ahead of Max Verstappen and Kimi Raikkonen.
Lewis Hamilton savors the moment after clinching his fifth F1 world title with fourth place behind Max Verstappen in the Mexican Grand Prix.
Race winner Kimi Raikkonen is flanked by second-placed Max Verstappen (far left) and Lewis Hamilton, who finished third after a thrilling US Grand Prix. Hamilton increased his title lead to 70 points over Sebastian Vettel ahead of the final three rounds of the championship.
Race winner Lewis Hamilton had plenty to celebrate after claiming victory in the Japanese GP at Suzuka to lead the world championship by 67 points with four rounds remaining.
Lewis Hamilton (no 44) overtook fellow Mercedes driver Valtteri Bottas under team orders on his way to a decisive victory in the 2018 F1 title race as he extended his advantage over Sebastian Vettel to 50 points.
Lewis Hamilton led from pole position in his famous No.44 Mercedes and took his seventh victory of the season on the Marina Bay street circuit in Singapore.
Hamilton stormed to a record-equalling fifth Italian Grand Prix victory -- overtaking both Ferraris in the process.
Lewis Hamilton celebrates with the trophy on the podium after winning the Hungarian Grand Prix at the Hungaroring near Budapest to extend his title lead over Sebastian Vettel to 24 points.
Hamilton celebrates an extraordinary comeback win at the German Grand Prix to give him a 17-point championship lead as title rival Sebastian Vettel crashed out
Dutch driver Max Verstappen claims a dramatic victory at the home of Red Bull Racing. But how does that impact the Drivers' Championship?
Sebastian Vettel took full advantage of a bizarre incident involving both cars of the American-owned Haas team to claim the opening race of the 2018 Formula One season in Australia.
Vettel -- 25 points
Hamilton -- 18 points
Raikonnen -- 15 points
Vettel won for the second time in as many races at the Bahrain Grand Prix. But the Italian team's victory was overshadowed after one of its mechanics suffered a broken leg when he was hit by Kimi Raikkonen's car during a pit stop.
Vettel -- 50 points
Hamilton -- 33 points
Bottas -- 22 points
An inspired Daniel Ricciardo claimed a remarkable and unexpected victory from sixth on the grid after a tactical masterstroke by his Red Bull team in Shanghai, with furious championship leader Vettel back in eighth place.
Vettel -- 54 points
Hamilton -- 45 points
Bottas -- 40 points
Lewis Hamilton was the chief beneficiary of a late puncture suffered by his Mercedes teammate Valtteri Bottas as he clinched his first win of the season at April's action-packed Azerbaijan Grand Prix.
Hamilton -- 70 points
Vettel -- 66 points
Raikkonen -- 48 points
After his unlikely victory in Azerbaijan, it was a second straight win for Hamilton as he bids for a fifth world championship -- and it could not have been more comfortable.
Hamilton -- 95 points
Vettel -- 78 points
Bottas -- 57 points
Ricciardo nursed his ailing Red Bull to a remarkable victory on the streets of Monte Carlo and with it made up for his 2016 heartbreak on the same circuit.
Hamilton -- 110 points
Vettel -- 96 points
Ricciardo -- 72 points
Sebastian Vettel's 50th career victory saw him replace Lewis Hamilton at the top of the championship standings to cap an emotional day for the Ferrari team.
Vettel -- 121 points
Hamilton -- 120 points
Bottas -- 86 points
Briton Lewis Hamilton won the first French Grand Prix since 2008.
The Mercedes driver avoided the worst of a dramatic start that saw title rival Sebastian Vettel clip Valtteri Bottas. Both drivers sustained damage in the collision, forcing them to pit early them and fall to the back of the grid.
Hamilton -- 145 points
Vettel -- 131 points
Ricciardo -- 96 points
Red Bull's Max Verstappen won a dramatic Austrian Grand Prix as hitherto championship leader Lewis Hamilton and Mercedes teammate, Valtteri Bottas, were forced to retire.
Vettel - 146 points
Hamilton - 145 points
Raikkonen - 101 points
Home favorite Lewis Hamilton was denied a sixth victory at the British Grand Prix as Ferrari's Sebastian Vettel took control of the championship at Silverstone
Vettel - 171Hamilton - 163Raikkonen - 116
Hamilton fought back from 14th on the grid to claim an astonishing victory as Vettel crashed out at Hockenheim.
Hamilton - 188
Vettel - 171
Raikkonen - 131
Hamilton went into F1's summer break with a season-high 24-point advantage in the title race over Vettel after winning at the Hungaroring.
Hamilton -- 213 points
Vettel -- 189 points
Raikkonen -- 146 points
Fernando Alonso's car was launched over the top of Charles Leclerc on the opening corner of the Belgian Grand Prix. Sebastian Vettel went on to win at Spa to cut Lewis Hamilton's lead at the top of the Driver Standings to 17 points.
Hamilton -- 231Vettel -- 214Raikkonen - 146
Ferrari's sea of fans -- the 'Tifosi' -- hold up a flag making fun of Lewis Hamilton, but he has the last laugh, winning the Italian Grand Prix for the fifth time
He ultimately decided to compete and on the day of the race, Senna lost control of his car and hit a concrete wall at an estimated 190 miles per hour.
The force of the impact sent part of the suspension back into the cockpit, fatally injuring Senna.
Some of the many changes implemented following his death included limiting engine size and power and raised cockpits sides to offer drivers more protection. Suspension also changed to prevent wheels from becoming disconnected.
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Jules Bianchi, Suzuka 2014
Jules Bianchi receives urgent medical treatment after crashing during the Japanese Grand Prix.
So effective were the new safety measures, there wasn't another F1 fatality until Jules Bianchi's crash -- and subsequent death nine months later -- in 2014.
On lap 42 of a rain-drenched Japanese Grand Prix, German driver Adrian Sutil lost control and crashed his Sauber, prompting a recovery vehicle to be called out.
One lap later, Bianchi lost control on the same corner and crashed at 78 miles per hour into the 6500kg crane clearing Sutil's car.
Following a lengthy investigation, the FIA deemed that there were several factors, rather than just one, which contributed to the Frenchman's death.
These included the "semi-dry racing line" on the turn where both drivers lost control, Bianchi's helmet hitting the underside of the crane and his failure to slow sufficiently.
Following the investigation, the FIA introduced the "four-hour rule," -- meaning races held during the day should take place no less than four hours before sunset -- along with changes to track drainage and how emergency vehicles respond to crashes.
Niki Lauda, Nürburgring 1976
Niki Lauda suffered severe and permanent burns following his crash.
Niki Lauda had four of his fellow drivers to thank for making it out of his Nürburgring crash alive.
Bad weather and track coverage meant that parts of the Nürburgring circuit during the German Grand Prix were wet, while other parts remained dry.
Lauda lost control of his Ferrari on the notoriously dangerous "Bergwerk" corner and smashed into a bank of earth, causing the car to burst into flames and bounce back onto the track where it was then hit by Brett Lunger.
The American rushed over to Lauda, who was trapped in his car, and along with the help of fellow drivers Harald Ertl, Arturo Merzario and Guy Edwards managed to free him after a minute.
Initially able to walk away from the wreckage, the Austrian fell into a coma on the way to hospital having inhaled gases that damaged his lungs.
Lauda suffered severe and permanent burns to his head, losing most of his right ear and his eyelids but remarkably missed just two races and returned at Monza six weeks later, finishing fourth.
The crash happened at a point on the 22.8 km Nürburgring circuit that was near-impossible for rescuers to reach. It resulted in the track being pulled from the calendar the following year.
Thirteen drivers, Spa-Francorchamps 1998
30 Aug 1998: The Ferrari of Eddie Irvine and the Maclaren Mercedes of David Coulthard loaded on a recovery vehicle after the crash.
If the five driver retirements after the first corner at Sunday's Belgian Grand Prix seemed chaotic, spare a thought for the 13 who were wiped out within seconds in 1998.
The downpour at Spa that year was so heavy, most of the cars were barely visible on the television feed through the rain and tire spray.
Despite more than half the field crashing out, the race was restarted more than an hour later using the teams' spare cars -- though this rule has since been abolished to reduce costs in F1.
Four of the 22 drivers couldn't restart the grand prix and there were several more incidents as the race wore on, including one that would impact that season's world champion.
Michael Schumacher, trailing teammate Mika Häkkinen -- who had already crashed out -- by just seven points, tried to lap David Coulthard.
With the Scot's car barely visible through the deluge, Schumacher smashed into the back of him and irreparably damaged his car, forcing him to retire from the race.
An angry Schumacher confronted Coulthard and the pair had to be separated. With just three further races to go, Häkkinen went on to win that year's championship by 14 points.