This past Memorial Day weekend I was invited to a single-day sporting event that has caused 66 deaths since its inception, with one-third of the deaths being among spectators. The required "license" to enter the event provides a notice that". . . management regrets that its efforts as to spectator safety do not eliminate risk of injury to spectators." More importantly, from a safety and health pro's perspective, spectators are highly urged to use personal protective equipment while at the event. I just had to see for myself what this was all about.

I'm referring to the 87th Indianapolis 500 race, the world's largest single-day sporting event, attended by upwards of 500,000 spectators. Safety and health pros seeking to expand their views may find some interesting parallels between the Indy 500 and our nation's progress with occupational safety and health.

The first Indy 500 race was run in 1911, the same year that the American Society of Safety Engineers (ASSE) was founded. Indy cars today travel three times the top speed of the first Indy racers. And the American workforce then numbered a third of what it is today - but there was three times the number of workplace fatalities.

Reducing risks

Safety was just beginning to be taken seriously back in 1911, and the Indy 500 race was no exception. The rearview mirror, an essential safety feature on all cars today, got its first use at the first Indy 500 race. Indy 500 racecars and driver safety apparel and equipment are now a marvel of advancement. Although crashes in excess of 200 mph regularly occur, there have been no driver deaths during qualification runs since 1996 and there have been no driver deaths on race day since 1973.

Although surrounded by many apparent dangers, such as highly flammable fuel, the pit crews provide a choreographed activity with amazing speed and efficiency. Safety pros will realize that many hours of solid training and preparation is necessary to avoid injuries under such stressful and hazardous conditions.

This year, Indy 500 management expected about 200 people, including race crews and fans, to be treated for injuries and illness. Nearly 250 medical personnel, including 9 doctors, 20 nurses, and 90 EMTs and paramedics were present. Fourteen first-aid stations and 22 ambulances support the emergency medical personnel. Emergency helicopters are on standby, as are fire response vehicles, with each vehicle attended by four firefighters.

Hearing conservation

Noise from the roaring racecars at the Indy 500 is intense. Anyone who sits in the stands will experience very high, often uncomfortable, noise levels. Even spectators that view the race from afar in the infield sense the loud noise. But noise is part of the allure of the Indy 500. It seems to excite everyone.

Street vendors readily sell a single-set of disposable foam earplugs for one dollar. And veteran spectators bring their own hearing protection, many opting for the greater noise attenuation afforded by earmuffs. First-time Indy 500 spectators, who cannot imagine or appreciate how loud the noise can be, and elect not to bring or buy hearing protection, soon learn their mistake and end up shoving their index fingers into their ears. The Indy 500 must be the largest use of voluntary PPE anywhere. Amazing.

Hidden risk?

With all the safety advances at the Indy, how will risks be further reduced or explained to racers, crew, and spectators? I was especially curious about risks that are not readily apparent. For example, is the Indy 500 noise too loud for pregnant spectators?

My curiosity was aroused when I read about the mother of Sam Hornish Jr. (one of the leading Indy car racers). She was eight months pregnant with Sam Jr. when she attended the Indy 500. She believed Sam thought the noise was too loud because he spent the entire race kicking. But back when Mrs. Hornish attended the Indy 500 while pregnant with Sam, little was known if loud noise could adversely affect a fetus. At best it was subjective, and it's understandable to believe that a natural "earmuff" surrounds a fetus that the mother provides with her body.

But in the late 1990s, organizations such as the American Academy of Pediatrics and the American Conference of Industrial Hygienists described noise levels believed to be harmful to a fetus. ACGIH suggests that hearing loss could occur to a fetus, beyond the fifth month of pregnancy, at 115 dBC TWA (3-dB exchange rate) or 155 dBC peak.

At the 87th Indy 500 race, spending 50 percent of the time in Stand A and 50 percent of the time wandering the racetrack infield produced nearly 110 dBC TWA and slightly over 120 dBC peak noise exposure. Not loud enough to cause fetal hearing loss, but loud enough to create potentially unhealthy cardiovascular and endocrine effects on the fetus.

Continual improvement

The Indy 500, to me, provides a vivid example of how safety progress evolves. There are wins and losses, old hazards and new risks, and debates over voluntary versus mandatory protection. Supporters of auto racing in general point to safety equipment improvements over the years. Detractors respond that there have been more than 300 deaths during the past decade at all U.S. race events. Plus, they'll claim noise pollution is impossible to control, or that some race tracks lack even the most necessary protections such as a wall between the track and spectators.

Meanwhile, arguments continue about when voluntary safety features, such as the driver head and neck support device, should be made mandatory. A.J. Foyt, a four-time winner at the Indy 500, has stated with regard to the device, "I would never let anyone tell me what to wear."

I came away from Indy thinking safety is a continual improvement process that is too slow for critics, but too fast for others like A.J.