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Author Topic: RV Crash Analysis - Safety Statistics  (Read 39027 times)

Mc2guy

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RV Crash Analysis - Safety Statistics
« on: January 07, 2009, 01:35:59 PM »
Hi all,

I recently got a bug in my shorts about comments made in the media and other forums about the inherent safety/danger of RV's.  Since the VAST majority of the reports and comments seemed to be conjecture or anecdotal, I set out to find some factual statistics on RV safety.  As it turns out, there really isn't much available.  We'll that ain't gonna cut it for me.  I am part of the "I want it now generation" but I also have a minor is statistics, so it looks like I just created a little project for myself.

Ok, here goes.  I spent the last couple of days downloading all available NHTSA data on vehicle fatalities involving motorhomes and have initiated an analysis of several key factors in crash related deaths, since these seem to come up a lot in conversation.

1) Seat belt usage
2) Structural Integrity of the Vehicles
3) Seating position
4) Alcohol
5) Vehicle Ages
6) Brakes
7) Fires/Explosions (Propane et al.)

I would like to normalize this data to the statistical mean used by NHTSA which is million miles driven.  However, while NHTSA has a wonderful utility to allow me to download raw crash data, they do not seem to have information available for vehicle miles driven by class.  Does anyone have an idea where I can publicly source this information?  Specifically, I need to know how many miles motorhomes were drive in the U.S. for the last 10 years.  If that is not available, I could try to extrapolate an annual mileage based on registered RV's, however, even the number of registered motorhomes seems a difficult number to source.  Any suggestions?

I will be posting the results here for public consumption (and debate, I  am sure). ;)

Thanks in advance for any suggestions on data,
Christian
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John From Detroit

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Re: RV Crash Analysis - Safety Statistics
« Reply #1 on: January 07, 2009, 02:08:24 PM »
I, for one, as a retired police dispatcher, will be very interested in seeing your paper on this subject when you decide to post/publish it (and I would suggest you publish in a peer review for the obvious reason (Publish or perish))

One thing you might do is check the assorted state records departments.  Each state has reporting requirements, normally those are equal to or in excess of the federal standards for reporting.. So you might get more info from the state, epically in the case of fatals

Assorted other originations may be able to give you an estimate of miles driven too
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geodrake

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Re: RV Crash Analysis - Safety Statistics
« Reply #2 on: January 07, 2009, 02:11:58 PM »
Christian, thanks for taking this on.  I for one will be interested in seeing the results.
George Drake

Mc2guy

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Re: RV Crash Analysis - Safety Statistics
« Reply #3 on: January 07, 2009, 02:41:19 PM »
I, for one, as a retired police dispatcher, will be very interested in seeing your paper on this subject when you decide to post/publish it (and I would suggest you publish in a peer review for the obvious reason (Publish or perish))


We'll, I am studying for my MBA and have a second child due in May (plus a full time 60+ hour a week job), so I don't know if this analysis will make it to "published report" quality.  That said, this will be a statistically sound analysis subject to peer review.  I just may not write a full dissertation on it! ;D
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Gary RV_Wizard

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Re: RV Crash Analysis - Safety Statistics
« Reply #4 on: January 07, 2009, 05:11:17 PM »
Maybe you could get some help/funding from the RVIA? OTOH, maybe they don't want to know - might be bad news!
Gary
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rjf7g

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Re: RV Crash Analysis - Safety Statistics
« Reply #5 on: January 07, 2009, 05:46:18 PM »
Is your list of factors in any particular order?  Just putting this out there (along with a little more information - e.g., does age of the vehicle reflect the presence or lack of air bags or is there something magic about being 10 years old?) would be helpful to folks making decisions.
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Mc2guy

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Re: RV Crash Analysis - Safety Statistics
« Reply #6 on: January 07, 2009, 06:05:30 PM »
Gary,

I did write to RVIA requesting any ownership/mileage data that they would be willing to share so we'll see if they are responsive or not (although I doubt it given the "expos`e" media trend of late.  I managed to get some usage data from FMCA, although I am afraid their membership may not be representative, even though it is the best data I found to date.  I'll let you know how it goes.

rjf7g,

There was no particular order to that list.  I only included age to see if there was a discernible difference in safety in newer motor homes.  In fact, if others have any "parameters" they would like me to explore during my research, please let me know and I'll do my best. 

Christian
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ArdraF

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Re: RV Crash Analysis - Safety Statistics
« Reply #7 on: January 07, 2009, 06:16:20 PM »
Quote
number of registered motorhomes seems a difficult number to source

One really basic problem is finding out what each state calls a motorhome when it's registered.  California, for example, calls them "house cars" which probably dates to the 1920s when they first started to appear.  You're going to have to pin down what they're called before you can even think about getting statistics for them!  And then there's that fuzzy term RV which can mean anything from a trailer to motorhome and, yes, even a boat.  I heard someone once refer to our Class A diesel pusher as a "trailer" and another person called it a "mobile home."  I hope the states have it better defined!

This should be interesting.  My gut instinct says there really are not all that many motorhome crashes so there may not be much on it.  Motorhomers "I think" tend to drive shorter days, stay put if the weather is bad, drive slower than automobile drivers, and have a variety of other habits that might make them safer drivers overall and, therefore, less prone to accidents.

Quote
comments made in the media and other forums about the inherent safety/danger of RV's

It would be interesting to know where you heard some of these comments, because I haven't heard them.  Makes me wonder exactly what they were talking about because I don't believe motorhomes are inherently unsafe or dangerous and we've been motorhomers for over 35 years.  Somehow I doubt the veracity of someone who would make statements that RVs are either unsafe or dangerous.  What do the rest of you think?

ArdraF
« Last Edit: January 07, 2009, 06:19:11 PM by ArdraF »
ArdraF
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Jim Godward

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Re: RV Crash Analysis - Safety Statistics
« Reply #8 on: January 07, 2009, 09:32:34 PM »
SNIP

This should be interesting.  My gut instinct says there really are not all that many motorhome crashes so there may not be much on it.  Motorhomers "I think" tend to drive shorter days, stay put if the weather is bad, drive slower than automobile drivers, and have a variety of other habits that might make them safer drivers overall and, therefore, less prone to accidents.

It would be interesting to know where you heard some of these comments, because I haven't heard them.  Makes me wonder exactly what they were talking about because I don't believe motorhomes are inherently unsafe or dangerous and we've been motorhomers for over 35 years.  Somehow I doubt the veracity of someone who would make statements that RVs are either unsafe or dangerous.  What do the rest of you think?

ArdraF

I think that if you remember the pictures of the accident that Jean & Jan had where the front cabinets came down, you would think that there may be some danger in an RV in an accident.  I have been into my front cabinets and know I do not want to be in the front seats if we have an accident but I also know I will be.  The side cabinets are no better.  I try to keep loose items to a minimum but there are always some, computer, etc.  The old TV in my front cabinet weighs about 60# and in any kind of sudden stop it is going somewhere.  The forces get pretty large in quick stops and the furniture and cabinets are not built to take those forces especially when we load them up with stuff.

I think the assessment of the drivers may be partially correct in that we do drive slower for the most part but generally we are not really good drivers, just slower and more careful.
 and thus have fewer accidents.  I drive mountain roads frequently and seldom do I see a RVer doing really well on them.  Lane position, speed, shifting appropriately, leaving space for passing, etc.  It is especially bad on roads like the one between here and West Yellowstone in the Gallatin River canyon or the road to Yellowstone via Ennis.  There are others but you get the idea.   :)

Jim
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Mc2guy

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Re: RV Crash Analysis - Safety Statistics
« Reply #9 on: January 08, 2009, 01:25:10 AM »
Well, after an exhaustive dive into the DOT and Bureau of Transportation Statistics (BTS) annals, I discovered a project called the National Household Travel Survey or NHTS.  This survey is conducted periodically every 6-10 years or so.  The most recent survey was conducted in 2001 so the information is somewhat dated, however, it does have a highly reliable estimate of motorhomes in use and how many miles they are driven on average.

This should give me enough information to normalize the FARS data from NHTSA to mileage and to extrapolate for years subsequent to 2001.  I've started to parse the data and should have some preliminary results by tomorrow.
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edjunior

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Re: RV Crash Analysis - Safety Statistics
« Reply #10 on: January 08, 2009, 07:45:45 AM »
Well, as Ardra kinda pointed out, you actually started this using the term "RV", then went to using "motorhome" only.  These stats would be kinda interesting, especially if you could break it down into the various types of RV's.  At least what we would consider the "major" types, or classes (Motorhome, 5th Wheel, Travel Trailer (which would include Pop-ups and Hybrids)).  But that may be asking a bit much, since I'm not sure what your data includes.
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Gary RV_Wizard

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Re: RV Crash Analysis - Safety Statistics
« Reply #11 on: January 08, 2009, 07:59:00 AM »
I think you are likely to find all sorts of statements about RVs being unsafe/dangerous and some more that say just the opposite.  The RV Consumer Group, for example, has made a lot of statements that appear to be little more than conjecture about what could happen in a crash.

But having seen what happened inside our 24 foot travel trailer in a one car crash, I can't be too critical of their opinions, unsubstantiated or not.
Gary
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John From Detroit

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Re: RV Crash Analysis - Safety Statistics
« Reply #12 on: January 08, 2009, 08:23:46 AM »
IN many areas there is a balance sheet

For many years the recommendation is that you follow the vehicle in front of you no closer than the distance you cover in TWO SECONDS.   (This is easier than doing the math and estimating the two feet per mph (one car length for every 10 mph) method

Just 2 seconds, One thousand one, one thousand 2  IN adverse conditions 3 or 4 seconds (or more)

More recently I've been told 3 is better (I tend to agree) and they wanted me to add 1 second for every 20 feet of vehicle (I disagree so long as all wheels brake, which is one of the reasons I believe in supplemental brakes... NOTE to O/P.  See if you can factor that into your calculations too.....  Did the RV have all wheel braking)

I think when someone is sitting in the captain's chair of a $200,000 plus house on wheels.... They drive more carefully (As a breakable rule)

Of course, there are always exceptions.
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Mc2guy

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Re: RV Crash Analysis - Safety Statistics
« Reply #13 on: January 08, 2009, 11:41:59 AM »
edjunior,

I did use the term "RV" when I started this post, however, I had intended to limit this to Motor homes.  Non-motorized RV's, as far as I can tell thus far are not included in the accident reporting information other than when indicating that a trailer was being towed.  There is no way to parse that data specifically because the accident investigator/officers report refers only to the vehicle in which the individual was injured.  If they were a passenger in a trailer, then I do not believe it would show up in the FARS data base in a discernible category, rather it would be grouped into a large category for people injured who where in a motor vehicle (think bystanders or pedestrians).

John in Detroit,

I'll see what I can find on braking, but I don't think that is going to be available.  I will isolate when a towed vehicle was present, however.

All,

Getting some results now, some surprising, some not...I'll have a "first pass" of high level information later this afternoon.

Christian
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Gary RV_Wizard

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Re: RV Crash Analysis - Safety Statistics
« Reply #14 on: January 08, 2009, 01:50:54 PM »
The potential problem is that the term "RV" is not used consistently. To some, an "RV" is a motorhome as opposed to a trailer, while to others it is generic "recreational vehicle".  I wouldn't lose sleep over it, but its something to keep an eye out for if data seems inconsistent.
Gary
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John From Detroit

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Re: RV Crash Analysis - Safety Statistics
« Reply #15 on: January 08, 2009, 04:35:55 PM »
Suggestion.. Don't limit your study to just Motor Homes

But DO... run seperate sheets for Motor Homes.. 5=ers TT's and so forth

Then run one sheet for "overall" (I will let you decide)

IE: Motor home, 5-ER  TT over 20 foot,  (On over all sheet)  TT-20 & under and Pop Up (seperate but not on the overall)

Or "Trailers over 2,000 pounds" on sheet (All kinds) and "under 2,000 pounds) not on sheet..

Logic: Trailers under one ton often do not have trailer brakes of any kind.
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Mc2guy

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Re: RV Crash Analysis - Safety Statistics
« Reply #16 on: January 08, 2009, 04:42:06 PM »
Here are some first pass results from the analysis. I apologize for the very long post.  If you are not interested in the methods, please skip to the "Preliminary Results" section below.

Before I get into the data, I want to explain my methods so anyone interested can understand what assumptions had to go into this information.  I will provide a detailed methods document sometime down the road once I am done with the review.

Objective:
To assess the statistical "safety" of motorized RV's driving in the United States relative to other forms of highway vehicles and assess any patterns or outliers with respect to crash injury, causation, or circumstances. 

Data:
The primary data utilized in this analysis was sourced from the National Highway Traffic Safety Administration's Fatality Analysis Reporting Statistics database or FARS.  This database is a consolidated listing of all traffic fatalities in the U.S. and is compiled annually from accident reports from field officers.  This database accounts for a variety of accident parameters including vehicle type, where the passengers were sitting, restraint usage, road conditions, impact points, alcohol use, etc.  This is the fundamental source of data for the analysis.

In order to normalize the FARS data against other vehicle types, I decided to use NHTSA's standard metric, which is fatalities per 100 Million Vehicle Miles Traveled.  This required knowing how many miles were driven my motorized RV's in the U.S. in any given year.  Unfortunately, that is not a standard statistic tracked by NHTSA, DOT, or the Bureau of Transportation Statistics.  However, I did find that BTS has performs a detailed survey of U.S. Household travel statistics once every 6-10 years and that survey does include motorized RV's.  The survey, known as the National Household Transportation Survey, was last conducted in 2001.  This survey provide me with a data point for the number of motorized RV's on U.S. highways, and the average annual mileage driven by these vehicles.  I cross referenced this to the 1995 NHTS survey to ensure the values where within an acceptable spread and they were within 5% for annual mileage, and tracked in parallel with overall vehicle ownership, so they were deemed useable.

Extrapolation Assumptions:
Because the NHTS data was for 2001 only, I needed to determine a way to extrapolate for 2000-2007.  The method I chose was to assume that motorized RV travel would track overall highway miles driven by "heavy, unit-body trucks with a minimum of 6 wheels", which is a statistic that the BTS tracks annually.  This category would include box trucks, heavy utility, and emergency vehicles, along with motorhome chassis, but NOT tractor cabs or linked trucks.

Potential Problems:
There are two potential data discrepancies that I must point out before I present the information.  I don't believe they have any significant impact on the results but I need to make you aware.  First, the FARS data puts Mothorhomes into three categories; light truck chassis (Class C) based motorhomes/campers; heavy-truck chassis (Class A) based motorhome/campers; and "unknown" chassis (Class A or C) based motorhome/chassis.  This leads to the problem of correlating motorhome mileage to heavy-truck mileage.  I don't believe that really should be of any significant impact considering that even if the correlation is using a skewed ratio, the overall rate of travel miles in the U.S. is relatively consistent across all vehicles (all categories tend to parallel each other therefore the general trend should hold).  The second problem is that RV/motorhome ownership has increased faster than the overall miles travelled in the U.S.  That means that they are likely a higher share of overall miles travelled than I am crediting them with for years 2002-2007.  This makes the motorhome look less safe because I have deflated the denominator of 100 Million Miles, so keep that in mind when reviewing the information

Preliminary Results:
The following constitutes preliminary findings based on the above assumptions.  A more detailed analysis of elemental factors will follow as time permits over the next several days:

See Revised Summary Below.

[b]Summary [/b]- From the years of 2000-2007, 843 individuals died in motorhome crashes in the U.S.  This averages to about 105 people per year.  This compares to the national total of 305,948 during the same period, for an annual average of 38,944 fatalities per year.  While the total number of deaths each year was quite low, the overall rate of fatalities for crash victims per mile driven in motorhomes was slightly higher than the national average fatality rate for the years 2000-2006 at 1.63 vs. 1.48.  Chart 1 below shows the comparison of fatalities per 100 Million Vehicle Miles Traveled for motorhomes vs. the national average for all vehicles.  The statistically safest category for motor vehicles per mile driven is passenger cars, which averaged about 1 fatality per 100 Million Miles

Specific parameter will be detailed more later, but a few conclusions can be drawn from the initial observations.
1) Seating position appears to have a large impact on the rate of fatalities with front seats (driver or passenger side) representing nearly 68% of the fatalities.  It is likely that these seats are occupied at a much greater frequency than the rest of the vehicle so this number may not represent anything significant.

2) The use of restraints makes more of a difference for rear-seat passengers than front seat passengers.  Over 85% percent of rear seat passenger fatalities were unrestrained, whereas only 11% of front seat fatalities were.

3) The initial "harmful event" that lead to the fatality (this does not necessarily mean that this event was the direct cause, only that it "started" the crash) was overwhelmingly due to striking another vehicle in your roadway.  This was followed by roll-overs/laydowns second and vehicle fires third.

4) There were very few crashes where alcohol appeared to be involved (less than 3%)


Thanks for your patience, more to come soon.  Looking forward to comments/feedback/requests.

Christian
« Last Edit: January 09, 2009, 03:28:15 PM by Mc2guy »
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ArdraF

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Re: RV Crash Analysis - Safety Statistics
« Reply #17 on: January 08, 2009, 05:36:56 PM »
Jim and Gary,

Several years back a Monaco Class A (can't recall exactly which model but it was top of the line) was driving alongside a flatbed truck carrying a piece of heavy construction equipment.  The truck driver apparently didn't think about his overhead clearance because he hit the underside of a bridge with the top of the Cat.  That caused the piece of heavy equipment to slide toward the Monaco in the next lane.  Unbelievably it hit the Monaco passenger compartment.  I would have expected the cage to be smashed in but it wasn't.  It damaged the front right side and luckily there were only minor injuries to the man's wife who was belted in the passenger compartment.  His granddaughter was in the lounge and not hurt at all.  I saw the pictures and was impressed with how Monaco built the cage around the driver compartment.

Can you imagine seeing this huge piece of construction equipment tipping over in your direction?  It must have been a terrifying experience.  Anyway, based on that accident, I think Monacos at least are pretty well built which is one reason I took the position I did.  Now, by contrast, we had a neighbor who drove from San Francisoco to Orlando in little over two days (around the clock with several drivers at maximum speed) and couldn't understand why his cabinets shook off the walls.  It didn't surprise us because he abused the vehicle, but I doubt that model was very well constructed to begin with.  What I'm getting at is some of the statistics might be skewed based on the whole low-end vs. high-end part of the equation.

ArdraF
ArdraF
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ArdraF

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Re: RV Crash Analysis - Safety Statistics
« Reply #18 on: January 08, 2009, 05:41:47 PM »
Christian,

Interesting so far.  Maybe when you're finished you could go to our survey section and ask how many of us have actually been in an RV accident and how many of us know of someone else who has been in one.  The results of that inquiry might correlate with what you're doing - or not!  ;D

ArdraF
ArdraF
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Gary RV_Wizard

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Re: RV Crash Analysis - Safety Statistics
« Reply #19 on: January 08, 2009, 05:46:52 PM »
I think some of the data assumptions are arguable, but it's a good piece of work given the lack of decent raw data.  I am not surprised that the motorhome fatality rate is similar to but slightly greater than the overall average.
Gary
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Mc2guy

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Re: RV Crash Analysis - Safety Statistics
« Reply #20 on: January 08, 2009, 06:23:38 PM »
I think some of the data assumptions are arguable.

Gary,

I agree, which is why I pointed out a couple of potential data problems.  They only relate, however, to the normalization factor, not to the absolute fatality statistics.  Those can be read with a good deal of certainty given the absolution nature of the reporting system.

I am interested if anyone has another option for mileage data given the scarcity of it at the federal level?

Also of note, the reported average mileage for a motorhome in the NHTS was 4238 miles per year.  This is low relative to the value that FMCA reports of their membership, which is 9000 per year according to their survey.  FMCA does not release their survey so it is impossible to determine how their numbers correlate to the Bureau of Transportation Statistics, but you could argue that the average mileage should be higher than 4238.  This would lower the overall rate of fatality in the motorhome class compared to other classes.  Unfortunately, without a better/transparent source for that information, this is the only defensible number that can be derived.

More later this evening on accident causation, driver response, vehicle age, trailer presence, etc. :-X


« Last Edit: January 08, 2009, 08:16:47 PM by Mc2guy »
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John From Detroit

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Re: RV Crash Analysis - Safety Statistics
« Reply #21 on: January 08, 2009, 08:05:11 PM »
About the only data that's "Assumable" in those figures are miles driven.. that is an estimate

However most everything else is somebody going 1,2,3,4,5 as it were... However even there there is an issue with Non compliance

Police agencies are required to investigate ALL fatal accidents and to report all fatalities to the NHTSC.

They are required to report on alcohol use, blood alcohol level, seat belt usage, air bag deployment and a host of other things

(I used to have to type the prelim reports)

However some agencies are less than compliant in making those reports.
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Re: RV Crash Analysis - Safety Statistics
« Reply #22 on: January 09, 2009, 09:29:46 AM »
The RVIA estimates that a typical RV (all types, not just motorhomes) travels about 6000 miles/year, but I suspect that is somebody's conjecture.
Gary
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Re: RV Crash Analysis - Safety Statistics
« Reply #23 on: January 09, 2009, 09:33:12 AM »
Quote
About the only data that's "Assumable" in those figures are miles driven.. that is an estimate

Yes, but there are a couple big assumptions in there related to mileage and mileage is a critical component of the calculation. It's the divisor in the equation and you don't have to tweak the divisor much to substantially alter the calculated fatality index
Gary
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Mc2guy

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Re: RV Crash Analysis - Safety Statistics
« Reply #24 on: January 09, 2009, 10:58:40 AM »
Yes, but there are a couple big assumptions in there related to mileage and mileage is a critical component of the calculation. It's the divisor in the equation and you don't have to tweak the divisor much to substantially alter the calculated fatality index

Gary,

I am comfortable that the denominator derived from the National Household Transportation Survey data is in fact accurate for the survey year.

The 2001 survey had 139,000 responses.  Of those responses 958 reported driving or owning a motorhome or "motorized" RV.  The NHTS corrects for certain demographic factors in the response pool and generates an "escalation factor", which is just a multiplier used to normalize the number of survey responses for the entire U.S. population (see table below).  When that was done, the estimated number of motorhomes in the U.S. comes out to 1,400,452 in 2001. The RVIA reports total RV (non-motorized included) ownership in the U.S. in 2001 at around 7,000,000.  RVIA Sales reports show that the typical ratio is 20-25% motorhomes sold to 75-80% non-motorized RV's (rough average).  This ratio supports the NHTS number since 20-25% of 7,000,000 would be 1.4 to 1.75 Million, consistent with the reported NHTS data.

Each household in the survey also reported the number of miles driven by each vehicle.  Motorhomes were reported as being driven an average of 4,268 miles per year, and that includes a large number of responses that listed 0 miles.

Taking the product of the average miles driven and the number of motorhomes results in a total number of miles driven by motorhomes in the U.S. in 2001 of 5,977,129,136, which is the denominator in our fatality rate equation.

Given the strength of the NHTS data, I am highly confident of the 2001 mileage information.  Where the soundness of the data becomes less certain is when you extrapolate out for years 2000 and 2002-2006.   I assumed that motorhome miles driven would correlate with the number of miles driven for large, single unit, heavy trucks with 6 wheels or more since that is a category tracked by the Bureau of Transportation Statistics for each year.  I believe that assumption is reasonable, but you could argue that linking motorhome miles to that category would UNDER-report miles driven since motorhome have become more popular in the last 5 years.  Regardless, the impact on the result will be very small (less than 5% at most).

Anyway, sorry for the long post, I just want to be transparent in the assumptions.  I have significant revisions to discuss in my next post since I discovered some problems with the actual fatality listings last night.  More soon.

Christian




Christian, Jenn, Holden, Emerson, and Fletcher
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Mc2guy

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Re: RV Crash Analysis - Safety Statistics
« Reply #25 on: January 09, 2009, 04:41:30 PM »
Ok,

Sorry for the retraction above.  I ran into a significant problem with the FARS data and needed to refresh all of the analysis with the revised figures.  I had been using data from the "PERSON" file, which lists every victim separately.  The FARS Coding Information Guidebook gives specific guidance that if there is an entry in the database, there was a fatality.  This turns out NOT to be true.  I have since discovered that all persons in a crash where "A" fatality occurred will be listed, regardless of whether they themselves died.  I reanalyzed the data using only persons with a listed "date of death" (macabre I know, but no way around it).  I cross referenced this against the "VEHICLE" files for each year 200-2007.  The VEHICLE file lists only the vehicles involved in crashes and how many individuals perished in the listed vehicle.  I now have an exact match across the two data files AND a third confirmation using the FARS summary reports for total fatalities in a given year.  Lastly, I had my sister, who has an MS in statistics review my work this time, and she agreed with the revised findings.

So what does that mean? ???

It means the data I submitted yesterday grossly overestimated the rate of fatalities :-\ I sincerely apologize for that.  The following constitutes a revised and verified summary findings:

Summary:
The revised FARS analysis shows that a total of 212 individuals perished in motorhome accidents in the years 2000-2007 for an average of just over 26 fatalities per year.  This represents an average rate of fatality of 0.44 per 100 Million Vehicle Miles vs. 1.48 for all vehicles in the United States, or roughly one third the average rate of all motor vehicles.  (See Chart "Fatality Mileage Normalization Chart")

Observations:
1) The "Initial Harmful Event" which is the event deemed to have caused the crash, was overwhelmingly due to striking another vehicle in "your" roadway (45%).  That can mean a vehicle traveling the same direction of a divided highway, or a vehicle traveling in either direction of an undivided road.  Vehicle Roll-over, Striking a Guard Rail, and Striking a Tree, each represented approximately 9% of total crashes respectively. (See Chart "Initial Harmful Event")
2) The majority of fatalities occurred in the front seats of the motorhome, with 80% being either the driver or passenger.  Of the 26 rear compartment fatalities, only 2 persons died while using a restraint (seat belt).  No children using child safety seats died during the analysis period. (See Chart "Fatalities by Seating Position and Restraint Usage).
3) Alcohol did not appear to be a significant contributor to motorhome fatalities. (Less than 1% reported drinking as a factor)
4) The majority of fatalities occurred on rural interstates and/or major rural highways (54%). (See Chart "Road Type")
5) Trailers of any type were only reported in 26 of 212 fatalities during the study period.  Of those, only 3 were reported as towed vehicles, however that statistic was only added to the database in 2005 and is therefore statistically irrelevant. (See Chart "Fatality by Reported Trailer Use")

Conclusion:
It is difficult to come to any supportable conclusions about accident causation, however, what it is clear that motorhomes are statistically very safe relative to the overall vehicular population.  What limited fatal crashes do occur appear to be largely caused by striking other vehicles and fixed objects near the roadway and the resulting fatalities seem to most often occur in the front seat.  Given that there were only 26 reported deaths of individuals in the rear area and only 2 of those were belted, one can draw their own conclusion about the merits of using a belt.  This author draws solace in the fact that not a single child in a child safety seat perished during the study period.

I will continue to review the information and attempt to draw out any possible nuance in the information that the readers here might find useful, but I am comfortable myself in the knowledge that the activity is statistically quite safe.  I am also pleased to conclude that some exaggerated media claims of motorhomes being "death traps" that I have read are simply and astoundingly false.


Christian, Jenn, Holden, Emerson, and Fletcher
2015 Forest River Sunseeker 3170DS
2008 Winnebago Sightseer 35J (SOLD)

ArdraF

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Re: RV Crash Analysis - Safety Statistics
« Reply #26 on: January 09, 2009, 04:44:00 PM »
Christian,

If you ever get around to doing a survey of motorhomers on this RV Forum, it would be interesting to know the average number of miles driven per year by our members.  I should think that we have a large enough population that you could get some statistically significant numbers with which to extrapolate what's needed.

ArdraF
ArdraF
:D :D

John From Detroit

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Re: RV Crash Analysis - Safety Statistics
« Reply #27 on: January 09, 2009, 04:52:50 PM »
RE: Most fatalities are in the front seat

I think most motor home miles are driven by a a husband/wife or person/significant other team. (you can take that several ways and all of them are right).   Many RVers are retirees and do not travel with "kids" in the ride

This would load the percentages toward front seat, since that's all that's occupied in many, if not most,cases

Also, traditionally the right front seat is called the "Suicide seat"in the US. (And other left hand drive countries)

As the driver, in my rig, I am fairly protected against "Stuff" that comes flying up to the front if I stand on the brakes or hit sometihng  Wife, is not so protected

What protects me....... Main slide out
Nothing adds excitement like something that is none of your business
My Home is where I park it.

carson

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Re: RV Crash Analysis - Safety Statistics
« Reply #28 on: January 09, 2009, 05:02:55 PM »
I really have problems with 'Average' statistics. To me they don't mean anything. 10 fulltimers will skew the results of 1000 part-timers to a great degree. So what does it prove.

   Maybe one should go back in time and use the "bell curve".

Just an idle thought... A 'median' approach may be better.

What do I know..I ain't no statistician..

carson  Fl


 
Carson, 
 West Central Florida
Ex RV'er. (1995 Winnebago Adventurer)
2007 Buick Rendezvous, SUV / CROSSOVER

...Logic works like a charm...

Mc2guy

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Re: RV Crash Analysis - Safety Statistics
« Reply #29 on: January 09, 2009, 09:04:13 PM »
I really have problems with 'Average' statistics. To me they don't mean anything. 10 fulltimers will skew the results of 1000 part-timers to a great degree. So what does it prove.

   Maybe one should go back in time and use the "bell curve".

Just an idle thought... A 'median' approach may be better.

What do I know..I ain't no statistician..

carson  Fl



 


I agree to a certain extent.  There is no such thing as an average RV'er.  Everyone has discrete risk factors that will increase or decrease their risk parameters.  The exercise was intended to determine the probabilistic occurrence of death across a large spectrum to determine a "relevant" level of risk as compared to a national average.  Feel free to discount that if you like.

Using a median only makes sense when you have a large data set are are interested in what's in the middle.  It has little relevance to discrete event statistics with multiple outcome potentials.   There also isn't a large enough data set of fatalities for median to be relevant to anything other than perhaps annual miles driven. 

If there are any specific parameters you are interested in, I can try and isolate those and get back to you, however.  Just let me know.

Christian

Christian, Jenn, Holden, Emerson, and Fletcher
2015 Forest River Sunseeker 3170DS
2008 Winnebago Sightseer 35J (SOLD)