IMPBA noise rule & dB meters

[Don Ferrette]

Since Rod asked about how to move this I'm doing the simple cut & paste for him-

"Well,I had the dubious distinction of being the "first" boater to ever be DQ'd from an IMPBA contest for noise,and I did it with a .20 mono. ohmy.gif blink.gif I have to admit,I never expected my .20 mono to be the first boat to get DQ'd.Talk about being blind sided and sucker punched.

The story...........

During open water the [2] days prior to the race it became very obvious that the IMPBA noise rule and how it was going to be enforced was a live grenade just waiting to have its pin pulled.

Recoginizing this, the IMPBA Board of directors had a meeting the first race day,prior to the drivers meeting,the board pulled that grenade pin and decided that the rule would be enforced as written and let the chips fall where they may.

This is where I got involved......My first "B" mono heat was early in the day so for some unexplained reason,God chose me to be the noise test dummy.

Just like they said in the drivers meeting,I was given a warning in the first heat for being @ 96 DB's.

Using conventional thinking I made all the changes that I "knew" would put me under the limit and......what do ya know, that was a dismal B.S. failure and I was still 2 DB's over the limit at 94 DB's.The CD came to me "immediately" after the second heat and executed me.I was not allowed to run the third round the first day.I was done.

I considered challenging the Calibration of the DB meters being used in Evansville,but after a little thought I decided to let it go,suck it up and see where it went.

By then I really had a vested interest in this issue.I only took "1" boat to the Internats.....I had finished both heats I ran in......I was really in the hunt when I got DQ'd and not allowed to run the third heat.By 10:00AM the morning of the very first day,I was a memory at the 2006 Internats.

The next day at the drivers meeting,after all the powers to be had slept on the problem over night,the powers to be came back and said they might have been a little hasty and decided to relax the requirements a bit because it was obvious that just about everything we knew about noise and how to enforce it appeared flawed.

Now,Mikey said earlier that I was OK with the DQ and everything was just fine.That isn't totally true.

I am no martyr and I was not then or nor am now I very happy with the enforcement approach instituted on the second day.I was not able to run the third round the first day so even if I bitched I had already been executed.I had no less that 50 comments during the event of other racers saying you mean to tell me your 20 boat was louder than that whatever was running at the time?There was no way in hell that there weren't several boats that were never warned that were a dam sight louder than my 20 mono no matter what the DB meter said.

After being DQ'd,I checked those meters personally all during the week and it became obvious that something about the way we are checking noise levels was very flawed.

[When I learned this morning that John Equis meter read considerably different from the meters that were being used,some of my questions maybe are starting to fall in place. ]

Now I want to make something very clear,River City[the Evansville club] did absolutely nothing wrong.They did exactly what the B.O.D.'s instructed them to do.

They did a great job and the Internats came to a successful conclusion and if you saw some the thunderstorms we had,that took some doing.Not only did I get DQ'd but I also absolutely destroyed a $250.00 EZ-up.

With Margaritas,ice cream,EZ-ups and DQ's.......This trip ended up costing me about $200.00 a lap......but I still had a great time and would do it again in a heartbeat.

After thinking about all this during my 14 hour drive home I still realize that until somebody got DQ'd for noise,this problem would never come out from under the red state/blue state rock its been living under and only then would it receive the research and attention it needs to serve model boating.

I personally am tired of this red state/blue state bullsxxt approach to the noise issue.

We are all boat racers here.There is no great Satan here looking to take your first born or turn you into a eunuch.This is just a very passionate issue that needs to be massaged and healed.

Everybody,and I mean everybody,think about this problem and write down what you "know" to be true[not what you think to be true],and in a few days we will start a thread and get everyones thoughts and maybe we can get started on trying to fix this mess.

I do "know" the solution to this problem is not,[1] Throwing the noise suppression rule out forever or...... [2] DQ'ing everyone at a race,that appears to be over the limit after checking their noise level with a un-calibrated and un-certified DB meter.Those are not solutions. Thats a pissen match,and I for one am real tired of this pissen match.

Allan and Chris are absolutely right..........We all have to sit down and "re-think" about how we are going to research and formulate our DB testing procedures.

It is obvious we as of yet don't even know the right questions to ask about noise and how to measure and surpress our noise.

1.Naviga has had a very strict and inclusive noise rule in place for years and their boats are not abusive.

We may never be able to meet Navigas standards because of the fuels we use or for whatever reason,but we have to research and learn what we obviously do not know.

This "Naviga" remark has nothing to do with equating our noise levels with Navigas.All this is about is gathering information and procedures.I for one have no clue what noise numbers are attainable for our requirements.

[Hey Dave Marles and all you Naviga boaters,you know how Naviga tests for noise.Tell us how Naviga measures and enforces its noise rule.]

2.There also has to be a calibration standard out there somewhere that we can all use as a reference.I am looking into that right now.If we are going to play this game we all have to be on the same page.

I "know" there are instrumentation labs out there that can calibrate and certify DB meters.Maybe that would be a good place to start?

Tom,Maybe you can move this post to its own thread......I don't have a clue how to do it and I sure as hell am not going to try and type it over again.

Call it what ever you want.

Rod Geraghty"

Now that the new thread is started let's do EXACTLY as Rod asked, put our heads together in a positive way to get this fixed. The first thing I have to agree with is this-

"2.There also has to be a calibration standard out there somewhere that we can all use as a reference.I am looking into that right now.If we are going to play this game we all have to be on the same page.

I "know" there are instrumentation labs out there that can calibrate and certify DB meters. Maybe that would be a good place to start?"

Obviously if John Equi's meter, who is our IMPBA technical director, was reading very different from the host club's meter(s) then, to coin the phrase, Houston we have a problem. I think meter calibration is EXACTLY where we need to start. Without this the field will NEVER be level & it won't matter who chimes in on how NAVIGA does it or whatever. Personally, I think it should be done, at a minimum, anually & the host club is responsible for keeping current calibration documents on hand. Now, with that said, how do we go about this on a local level? :blink:

 

[Ronald van Essen]

Rod

Nice story Don and sorry for Rod's DQ

But what does the IMPBA rule book says all about the noise?

There I read about how to measure and about equipment.

how was that compared to what you saw at your event?

Was it an IMPBA event?

8. IMPBA Noise Rule

At all IMPBA sanctioned events all boats MUST meet the following conditions, and

boat operator accept the included mandates.

a. A commercially available noise measurement device (Radio Shack or

equivalent) must be used. The noise measurement device will be set to the "A"

weighted measuring scale, fast response.

b. The maximum allowed db level for IMPBA Sanctioned events will be 95db.

c. Measurements must be made from the shoreline area, between the starting line

and buoy #1. The measuring device will be set at a minimum height of 4' to 6'

above the ground, with the device pointed approximately 90 degrees to the

running path of the boats 25 feet back from the waters edge. Stable mounting

such as a tripod is strongly recommended. Care should be taken to assure the

operator of the measuring device is in a safe location.

d. If more than one measurement is made, the highest reading will be used. At the

discretion of the CD, a participant may be required to make a solo run to

determine a db reading. If a participant refuses to make a solo run, they will be

disqualified from the event.

e. Measurements will only be made on boats that are on the race course, and are

well underway (i.e., not getting on plane or being launched or in the pits). The

boat should be traveling approximately perpendicular to the direction the

measuring device is pointed, and the boat should be located approximately in

front of the measurement device in one of the racing lanes.

f. Measurement of the noise level should ideally be performed by the CD, but

he/she may be assisted by others appointed by the CD if this is not practical.

g. A competitor must be warned promptly after the CD determines that their boat

exceeds the db limit. If during the second round the boat still exceeds the limit,

the boat will be disqualified from competition. All points earned during the

first round will be valid.

h. The host club shall provide the measuring devise.

Okay now what other type of boats were out there? I don't know if there is a big difference for the classes, but that should not be a factor I guess. What about changing wx conditions, sound has something to do with temperature. I don't know if it will be much of a factor to our hobby or to measuring the sound level, but it might be worth looking at it.

PS I am interested in just some figures of different classes

Looking forward to the rest of the comments on this

Ronald.

 

[Tony Jacuzzi]

I completely agree with Rods thoughtful approach to this. I was part of the BOD's decision to enforce the rule as written on the opening day. It is and will remain my opinion that we are tasked with following our constitution and rules, evaluating whats right and wrong with our processes and then fixing them.

Reducing noise is the primary goal of the rule, what we are lacking in my opinion is a credible, repeatable, and sustainable testing process that removes all variables from the equation (site specific-equipment etc.).

My vision is that the testing is done at the stinger or some defined distance, with a certified piece of test equipment, at some pre-agreed db limit. This would all be part of the tech process, once teched your good to go. DB monitoring would continue during the races and if someone goes over then we re-tech to ensure no change has been made to the boat.

I think another thing we could consider would be to have a benchmark "mule" that would be used at the national events. By this I mean that a boat is built and tested and certified eg this boat would be certified at some db level at for example huntsville. That boat is then brought to the race site run and we would see if we can repeat the certified limit. If the mule runs 3 db over the certified level then we may have to make some allowable variance based on the mules performance. Just some thoughts although I am not a noise guy, just someone who has lost about 40% of his mid range hearing and has been forced to wear hearing aids since the age of 49.

Tony Jacuzzi

IMPBA-D2

 

[waltr]

Hello all.

Today I'll be having lunch with a friend that's an official of our local short tracks. He's the one that Tech checks DB readings on all the cars and trucks.I'm curious to see how they control consistancy.

Knowing that sound levels will change depending on the atmospheric conditions, a mule might not be a bad idea.

But on the other hand,I think we need to have some way of calibrating our own personal meters so that we know when we're testing at home,we're in the ball park.

Once we all get to a race,it's almost too late to correct a problem.

Later

 

[Geraghty]

Thanks for moving this subject to its own thread....

Needless to say,I was a zombie last night when I wrote my comments.There is one thing I forgot and would like to add.

Anyone who has been around this activity for any length of time has heard those un-muffled and muffled pipes for that matter that are just plain annoying to listen to.I have heard this in .20 boats also.My .20 boat had that annoying crack in Evansville.I paid attention to it in the second heat and its sound was different from the rest of the field.

The sound of those particular boats that "crack" substantially differs from the rest of the field and draws your attention to that noise.We have all heard it when a group of boats go by on the course and one of them differs from the rest.That "crack" literally stops conversations on the beach.I noticed my .20 boat had the distinction of having that "sharp irritating crack".

The inverse of that was also true in Evansville.Anyone who had a Copper quiet pipe or Cooper add-on silencer had that "mellow" exhaust report.While I was looking at the DB meters,those pipes that were Cooper equipped were just about as loud as some of those that were not but were not as irritating to listen to.

We all know that the 2 stroke exhaust report,under the best of conditions,has the ability to piss people off.

Mark Bullard this last week also mentioned the venturi noise of the air going supersonic thru the carb.It also can be irritating and add to the noise problem.

My point is,this noise mess is a complete package we have to address.I personally believe the carb,motor mount,and the exhaust all need to be looked at.

Rod Geraghty

 

[Don Ferrette]

.....I personally believe the carb,motor mount,and the exhaust all need to be looked at.

Agreed. The entire package needs consideration. One of the things often overlooked is how a hull resonates, I've seen this big time in 1/8 scale hulls & pay special attention to dampening said resonant vibrations.

On another note- about 3 years ago two rather well known guys from the NAVIGA circuit came over to the states & raced with us at the spring Hagerstown, Md race. They were Kjell Noddeland & Tore' Hilde (hope I spelled them right), both multiple NAVIGA World champs. They were every bit as fast as we were & gave myself, John Finch & few others some serious competition!!! But the thing that impressed me the most was between heats I was talking with Tore' and Kjell, being about 12-15 feet away, fired up his CMB90 powered SG. We didn't even have to raise our level of speaking to keep talking!! I think we stand to gain some valuable input from our NAVIGA couterparts on both noise abatement & how they go about enforcing their 80dB limit consistently.

 

[CharlieB]

This is an extremely important issue. I believe there are a few things we can do to improve the “INTEGRITY” of our noise-level testing.

First, almost everyone is running high-end equipment, boats, motors, and radios because we all want to be as competitive as possible. We seem willing to spend vast amounts of money to add a few MPH’s to a boat, but when we go to buy an important piece of equipment (Sound Decibel Meter), we settle for the cheapest one on the market.

Radio Shack’s web site only listed one unit when I searched this morning and it was a whopping $49.99, and it is advertised as:

“Restore balance to your life.

Get precise readings when you fine-tune audio response of a stereo, PA or home theater system in combination with an equalizer.

And,

Disclaimer: This meter should be used for home/hobbyist use only. This meter does not meet the requirements set forth by the American National Standards Institute (ANSI), Standard S1.4.

http://www.radioshack.com/product/index.js...rentPage=search

When I searched the web, I found Industrial strength Db Meters and Calibration units all the way up to $500 and they do meet the ANSI Standard.

Here is a site: http://www.monarchinstrument.com/Sound.htm

I suspect there is a difference in the quality and reliability of this equipment. I am not proposing that every club spend that much money, but for our annual Regatta, maybe we should demand high quality Dd measuring equipment that has been recently calibrated and certified. If we get DQ’ed then, at least it was with quality test equipment.

Moron’s post listed the IMPBA rules. In C #1 he says, “the unit should be positioned 4-6 feet above the ground”. What effect does this placement have if the unit is stationed on a hill 15-feet about the water, vs. readings taken 4-6 feet above the actual water level?

Just some of my initial thoughts for the groups consideration.

Charlie Blackwell………….

 

[Piston1]

I think it's simple from a Naviga perspective. Their Db limit is so low (80) that it minimizes external effects caused by pond shapes, weather, and or any other parameter previously discussed. Therefore a more realistic and consistent boat sound emmision assessment can be made. When you make a boat sound like whisper (like Don said), it will sound like a whisper no matter were it is. At 92db the sound propagation monster gets affected by to many external variables that nobody can control. Evansville proved that fact.

Another thing, calibration of the instrument is not the solution. We are using cheap instruments intended for general course sound survey in conjunction with go no go rules. That mix don't mix.

 

[Geraghty]

Another thing, calibration of the instrument is not the solution. We are using cheap instruments intended for general course sound survey in conjunction with go no go rules. That mix don't mix.

Some sort of calibration procedure has to be considered.....+/- 5 DB just doesn't cut it.Being DB reading levels are expotential,that just ain't close enough no matter how expensive the meter is.

 

[Piston1]

Assuming the instrument can be calibrated. That Cal report is probably going to cost you more than the instrument itself.

 

[AWaddle322]

There is a rumor out there that some one on the board (Jon Equi) I believe has the equipement to calabrate db meters but it is currently broken. It is also rumored that This piece of equipement is on its way home with Randell Thomas for repairs (new resisitor of some type). So maybe getting everyones db meter calabrated epoxing the adjusting screw fixed is one answere. But if you fix it such a manner that does not allow for it to be adjusted in the future how long are the going to actually keep accurate. If you do not fix it such a manner that keeps someone from adjusting the screw on the side of the meter then calabration means nothing in my opinion.

After doing a lot of thinking on Harry Gerharts Twin that was legal the weekend before and was illegal at the start of the nats. It may be real simple. All that would have to happen is the wind change direction (weekend before wind blowing away from db meter and during the internats wind blowing towrds the db meter).

There is a lot about noise that none of us know. we all have some opinion but it is just that an opinion. What I can tell you for sure is when Mac quite pipes are not quite enough and when the parabolic pipes are not quite enough we have a problem. The copper pipes are quite enough but with very limited test time I did not find the performance I am looking for ( i believe it has a lot of potential and I believe I can find what I am looking for in time).

Something else to consider. John Browns 60 and 80 had to have additional muffling devices added to get to the limit but his twin did not with what appereared to be the same pipes. How can a single be louder than a twin?

I just want to state that I am not bad mouthing or picking on any manufature on mufflers or muffled pipes. I am looking for answeres. I had two close friends pack there stuff up and leave the nats early with talk about never running model boats again. I personnally spent over $500.00 trying different muffling devices at the nats this week and as much stuff as I changed I guess I should really feel lucky that everything came home in one piece.

I for one have already loaded my OSHA book into my vehicle to carry home this evening to see what it may sheed on testing pprocedures for work place noise (I relize this is irrelevant but it may sheed some light on the subject). I would like to encourage anyone that can access any info on db readings from creditable sources to report your findings and be sure that you do not read into it what you want but rather the whole story.

Also one other thing that bothered be about the the nats is that they would tell you that you were over the limit but they did not in all cases tell you how much you were over the limit. I think that you should be told that you were at XX Db's. this would allow you to have a more educated guess in what to do to fix the problem. examples I sam John brown put a turn fin on his pipe and drop 2 db's . I also saw mark Bullard put diverters on his boat and drop 4 db's

Sincerley,

Allen "looking for answeres" Waddle

 

[Rick Doane]

I would recommend that a Industrial Hygenist be consulted (hopefully there is one who is a boater) to help us identify all of the variables to this issue. I know that the sound pressure is different for the wide range of frequencies we encounter and the sampling of those frequencies is most important. Also we need to consider other outside influences such as wind speed, temp., humidity, etc. Measurements of sound pressure are going to be different from location to location and there should also be a "plus or minus" involved when performing these measurements and at what confidence level (1 sigma, 2 sigma?). An example of this is if an instrument is showing a reading of 90 db, what is the specific error ( or total propagated error) of that measurement? 5%, 10%? At 5%, the error would be 4.5 db and at 10% it would be 9 db. Therefore, you have a measurement that could range between 81-99 db depending on the error.

Most good db meters have a calibration tool that can be ordered with it. It is also advisable that the meter(s) be returned to the manufacturer periodically for external calibration. Input from the European communty will also be most valuable. There are enough doctors, engineers and scientists in this hobby and on this board to come up with a reasonable approach if we had to.

 

[AWaddle322]

After reading the instuctions on this db meter that was used at at the internats they have +/- 2 DB'S. This means that it is perfectatly exceptiable for these meter to vary as much a 4 db form pass to pass. As gerarty said $200.00 per lap with a meter that has this consistance is a joke. Everyone neeeds to open there eyes and do it quick before alot of people get out of our hobbie. We do not have enough information to implament this rule. I for one am for quiting the boats down but at the expense of running boaters out of this hobbie there needs to be a little more leiancy than to dq someone from a class after 2 heats.

Allen

 

[Don Ferrette]

Here's a question- NAMBA has had a dB rule in place for YEARS, how it that rule being "policed" ... or is it?? :blink:

 

[Ronald Van Wagnen]

Reduce the nitro content, reduce the big "bang", have happy neighbors. I believe this is how for the most part your European cousins accomplish it.

inactive ron

 

[Piston1]

Allen, add more error due to operator error, cal drift, etc and you could end up with 5-6 db or more erroneous readings.

 

[Don Ferrette]

There is a rumor out there that some one on the board (Jon Equi) I believe has the equipement to calabrate db meters but it is currently broken. It is also rumored that This piece of equipement is on its way home with Randell Thomas for repairs (new resisitor of some type). So maybe getting everyones db meter calabrated epoxing the adjusting screw fixed is one answere. But if you fix it such a manner that does not allow for it to be adjusted in the future how long are the going to actually keep accurate. If you do not fix it such a manner that keeps someone from adjusting the screw on the side of the meter then calabration means nothing in my opinion.

Good point Allen. If the meters were calibrated then you wouldn't want them tampered with but you still need the ability to re-calibrate down the road. A solution to this might be a simple piece of "tamper tape", the kind that changes or says void if it's been pulled up. These tapes are big time popular these days on electronic equipment & computer cases & readily available. Just a thought.............

 

[Piston1]

DELETED.

 

[Rules]

As mentioned by others, I did send the calibration devise back with Randall Thomas for repair. He will fix it or if not, will report back that we need to get another calibrator. I for one was not expecting the wide variance that I saw between the 2 each db meters that Evansville had and the one that myself and Bruce Jacobs had. It did take a serious effort to compare 2 meters that had different display times to actually see the varience, but it was there. My meter was at least 5-6 db lower and the one that Bruce had, was 3-4 db lower. The published information that came with the meter stated plus or minus 2db at 114db SPL. Maybe they are accurate at that level, but apparently will not work where we need it. Randall and myself will find out what we need to do, to get reliable results for all of our meters.

We will have a calibrator that works, and will institute a program to insure all db meters read the same. The Radio Shack meter was selected as the meter of choice since it is widely available and cheap. I doubt that all of our clubs would be eager to spend $300-$600 on a db meter! I, as Tech Review have to consider something that will work on a national level and can be implemented, the Radio Shack devise was the only option.

Based on last years Regatta data, and what I had heard, myself and many others expected that there would be NO problems with noise readings at Evansville, NONE! While I was at the race, I did learn from our Gas Director Kevin Sheren, that he had observed sound testing that utilized a 4'x8' vertical wall placed beside the meter to limit stray noise from an unwanted direction.

I don't know the actual percentages, but there hundreds of boats that were legal and ran at the Regatta. We have identified problem areas and will move quickly to find solutions. Until then we need to use the rules that everyone voted upon and work towards a resolution.

 

I thank everyone for their compliance

at Evansville and rush to fix during the event,

John Equi

IMPBA Technical

 

[Don Ferrette]

We will have a calibrator that works, and will institute a program to insure all db meters read the same. The Radio Shack meter was selected as the meter of choice since it is widely available and cheap. I doubt that all of our clubs would be eager to spend $300-$600 on a db meter! I, as Tech Review have to consider something that will work on a national level and can be implemented, the Radio Shack devise was the only option.

 

As always thank you John for being right on top of this. With having the meters being set on one calibrator under controlled conditions this should help immensely.

 

We are moving in the right direction & there will always be bumps in the road, but we can acomplish this. B)