The XYZs of Gs:
Saferparks Weighs In on the Great G-Force Limit Debate

Dynamics was one of my favorite classes in college, but biodynamics is another thing altogether.  It's one thing to compute the acceleration of a rigid body under propulsion, but quite another to understand how a wide range of non-rigid human bodies will act, react, and interact within that dynamic system.  Combining human physiology with the physics of motion, and pushing each to its furthest limit, is a complex task -- even for the experts.  Now add in the economic pressures of the competitive marketplace, the rush to build newer/faster/higher/better thrill rides.  Finally, imagine that all those interdependent variables are being experimented on without any government safety oversight or public accountability.  That, in a nutshell, is Congressman Markey's concern.

Every year new thrill ride designs are brought to market.  Many of those new features push the boundaries of human endurance and further stress the limited resources assigned to monitor product safety.  There is no other industry on earth that, by its very definition, rides such a fine line between fun and disaster.  Common sense and rational science tell us that the physiological effects of those new technologies should be closely monitored.  Let's see how well that's working in the United States:

• U.S. amusement ride manufacturers and ride owners monitor injuries associated with their own products through injury claims filed by patrons.  Those safety records are not available to the public, and are not shared among competitors.
• The U.S. government does not monitor the physiological effects of high-g rides.  No federal agency has authority to oversee thrill ride safety.
• A patchwork of state and local agencies monitor operation and maintenance of some amusement rides, and the U.S. Consumer Product Safety Commission investigates certain equipment failures on traveling carnival rides, but there is no regulatory body that has authority to approve or disapprove a new (or existing) type of ride for commercial use in this country.
• There is no effective system for collecting data on ride-related injuries, no way for consumers to identify rides that present a danger to some (or all) patrons.

The lack of a centralized safety authority for U.S. rides puts an unrealistic burden on state and local regulatory programs.   State ride inspection programs are intended to address operation and maintenance issues, but more and more design-related issues are cropping up and nobody has budget, mandate, or authority to deal with them. 

Federal regulation is the logical place to address the issue of g-force limits, but so far the theme park lobby has stonewalled all attempts at federal safety regulation.  As current events attest, industry self-regulation is a pretty easy sell in Washington.  Congressman Markey's proposed legislation to bring thrill rides under the jurisdiction of the Consumer Product Safety Act has been stalled in a House subcommittee for three years.  The amusement ride industry condemns Markey's bill, calling it unnecessary, unworkable, and intrusive. 

With federal legislation mired in political quicksand, New Jersey decided to solve the problem itself with a new statute granting regulators authority to analyze and approve the design of any new thrill ride brought into the state.  The amusement ride industry has criticized the New Jersey law as well, calling it unnecessary, unworkable and intrusive. 

Expanding state safety regulation to encompass design issues might work for New Jersey, but most state and local agencies lack the authority and technical resources to take on design issues.  Even if it were politically and financially possible for each U.S. ride safety office to analyze the dynamic force profile for rides operated in their state, the rules defining those analyses would be different in each state.  That's not such a big deal for theme parks, but it makes life miserable for manufacturers and traveling carnivals.  They've got enough trouble navigating around the differences in existing state ride regulations.

Expanding federal carnival ride regulations to encompass permanent rides, as Markey proposes, will address some safety issues related to ride design.  Child safety features, for instance.  The Consumer Product Safety Commission has worked with the stroller industry, the bike trailer industry, and the bike seat industry to set standards for child restraints in open, moving vehicles used by toddlers and preschoolers.  Those common sense requirements should be translated to kiddie thrill rides, and the CPSC is the appropriate agency to do so.

The CPSC is not the right agency to research highly theoretical issues, such as the effects of multiple dynamic force parameters on millions of different human beings.  The g-force question requires a different approach.  This is how David Moulton, Congressman Markey's Chief of Staff, explains the difference:

"The bill [HR 1488] was not written to address the g-force issue. It simply restores CPSC's conventional jurisdiction to investigate accidents on amusement park rides.  In contrast, the impact of g-forces on riders presents a very unconventional issue -- injury arising from the proper operation of a ride where no accident occurs.  These forces are little understood but potentially lethal.  It is a very new, cutting-edge development that no one has adequately researched but it requires immediate intervention to set conservative limits so that the runaway speed-and-force combinations built in to new rides don't bust through human tolerances while we're doing the research.  So far, Rep. Markey has tried to get action from the industry and the public health community on g-force limits through non-legislative means, including 1) asking the National Institute on Neurological Disease and Stroke to look at it, 2) forwarding the NINDS material to ASTM and IAAPA and asking them to set reasonable limits, 3) asking the Brain Injury Association of America to have a blue ribbon panel assess the public health danger and a research agenda. Ultimately, this will require a national response."

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The New Jersey Department of Community Affairs and Congressman Markey are both concerned about the increase in reports of ride-related neurological injuries over the last decade.  New Jersey's ride engineers are creating a system of data collection and g-force analysis that should lead to a better understanding of the limits of dynamic force -- but only for rides operating in that state.  I applaud New Jersey for taking on this issue.  Yet the NJ prototype will not spread evenly across the country.  It is absurd to ask that every state and county regulatory agency research and set safe guidelines for dynamic force on thrill rides.  It is equally absurd to regulate thrill ride safety without addressing design issues as crucial as dynamic force. 

Congressman Markey is working a different piece of the puzzle, advancing research on the biological effects of high-g rides so that the evolution of thrill ride technology no longer outpaces our understanding of its effect on human beings.  That research is crucial to consumer safety. 

Yet research alone will not keep the amusement ride industry from pushing technology too far.  The industry can't be expected to ride herd on its own aggressive tendencies.  Success in the theme park business means boldly trying new ideas and selling them to the public as unblemished fantasy.  Regulation exists to temper the natural enthusiasm of business, to set limits, to be the bad guy.  You can't combine those two functions into one without losing the best elements of both.  Trusting industry to self-diagnose rare and obscure failures is utterly naive.  The amusement ride industry has no incentive to voluntarily report a possible connection between brain hemorrhage and capital equipment that has cost them tens of millions of dollars per machine. 

In short, we cannot expect any American business to police itself in terms of limiting new technology.  That's one of the purposes of government.  Our government, as in We The People.  Our government, the one that represents the 300 million consumers who pay the theme park lobbyists' salaries.  Our government needs to muster a little backbone and develop a workable set of checks and balances to ensure that market pressure in the theme park industry doesn't compromise consumer safety.  Congressman Markey can't do it alone.

We need a collaborative approach, but one designed for this particular problem.  The CPSC might be able to translate child restraint requirements from strollers to kiddie coasters (would someone please give them a political mandate to do so?), but the CPSC is not equipped to address rapidly evolving technologies unique to high-end thrill rides.

We need medical experts, ride design experts, and g-force experts from other industries working together.  Consumers need STRONG representation within the group to ensure that all pertinent data is looked at and all pertinent results are shared with the public.  We need to set up a credible system of checks and balances that applies equally to all rides and all ride owners, so that for-profit businesses no longer have carte blanche to experiment on their paying customers.

Each new thrill ride is an experiment.  That's not, in and of itself, a bad thing.  All businesses experiment on their customers to some degree.  I'm not suggesting that the experimentation stop, but I do think it's time to add a few controls, such as:

• Data collection
• Collaboration between industry, accident victims, and the medical community
• Independent verification (where independent does not mean "somebody else from the industry")
• Full disclosure to the public

What is missing in this industry is a rigorous and unbiased system of front-end product safety review and back-end failure analysis.  Failure data in the amusement ride industry is so well-hidden and fragmented that nobody, including the industry's own engineers, has a full picture of the potential dangers.  Concern over the outcome of civil lawsuits has taken precedence over responsible engineering practice.  That is the side of the industry that keeps me awake nights.

Before I had kids, I spent ten years as a software engineer working on space launch vehicles and weapons systems.  My work was closely regulated by NASA and the U.S. military program office.  In aerospace, the program office represents the end user, and they get to look at anything they want to.  They get to talk with anyone they want to.  Design reviews and accident investigations aren't considered a punishment or an attempt by government to humiliate an honest business.  They're just part of the job.  Nobody takes them personally.  They're certainly not fun, but they're invaluable learning tools.  I never worked on a project where I wasn't thankful -- in the end, anyway -- for the program office folks.  They helped us build better products.

The aerospace industry rides the cutting edge of technology, just like the amusement ride industry.  The aerospace industry shamelessly promotes its successes, just like the amusement ride industry.  The difference is that the aerospace industry is forced, by the government, to examine its failures detail by painful detail.  One failure can teach more about a system's performance than a million successes.  The theme park industry throws away those learning opportunities.  That is a waste of human suffering that I find intolerable.

I push for regulation because that's the only way I know to ensure that ride-related accidents are honestly and thoroughly investigated.  It's the only way that failure data can be shared among competitors, and between the industry and its customers.  Safety and secrecy are incompatible in any industry, but especially in this one, where millions of people every year are loaded into fast-moving mechanical equipment that they don't understand.

Different rides pose different risks to different groups of people.  New risk factors evolve with each new ride design.  Consumers need detailed information in order to make responsible choices about which rides are safe for them and their children.  Doctors need detailed information on the safety history of thrill rides in order to effectively treat and advise their patients. 

The only way we'll get that information is through reform.  We count on the theme park industry to push the limits of possibility and bring us new thrills every year.  We also count on the government to make sure those limits aren't pushed too far.  The industry is keeping up its end of the bargain.  Congress is not.

Are today's thrill rides causing brain injuries?  I honestly don't know.  I don't think anybody knows, with a reasonable degree of certainty.  What I do know is this:  there isn't an effective process for determining which rides are safe for which people.  We have to fix the process first.