Suction Entrapment Blog

NEW P&SS Act DVD/WEbinars

Tue, 1 Mar 2011 09:08:34 -0600

It has been more than a year (eek! almost TWO!) since I last posted on this blog. I am amazed that it still get’s so much traffic. It’s encouraging that people are finally coming around to correct the suction entrapment issues in public pools across the country.

I’ve been busy giving lectures, creating instructional material and even losing weight. It’s now time for us to once again reassert our best inspection glasses as we ready our pools for the 2011 summer. If you are a publicly operated pool, compliance was mandatory by December 19, 2008. If you own a residential pool, there is no mandate.

RESIDENTIAL POOL OWNERS TAKE NOTE: please consult with a pool professional in your area to disable/modify any pool drains/suction fittings in your pool. It doesn’t happen often, but they have killed children and adults.

I am now doing a bi-weekly (more frequent during this season) webinar for the US Consumer Product Safety Commission at:

www.GetPSSACompliant.com.

I’ll still update here occasionally, but most of my effort on compliance has been focused on creating the training materials for live webinars and the US CPSC DVDs (will ship in the upcoming months).

I have a backlog of topics to cover on this blog, just need to get around to posting them.

Thanks for dropping by!

It's Happened, Again.

Fri, 12 Jun 2009 12:00:38 -0500

What if drains are NOT contributing to circulation? How might that change your world?

Most of the content of this blog was supposed to appear next week, but I received a tragic email this morning and it's been troubling me...

A man (husband) was killed on the drain of a pool on April 11th in Pittsburgh. We don't have many details yet, but this appeared today on the newsfeed:

Wife of man who drown at athletic club files wrongful death suit

It will be interesting to see if this pool actually NEEDED a drain other than the great state of PA mandating one. Time will tell, but history records and sometimes it is history that teaches us the best lessons.

So let's take a look at language on circulation for all, but about 9 states in 1928:

VII. Inlets and Outlets

A. All pools should be provided with an outlet at the deepest point of sufficient size to permit the pool to be completely drained in four hours or less. Outlet opening in the floor of the pool should be at least four times the area of the discharge pipe ,to reduce suction currents. This opening must be covered with a proper grating.

B. In rectangular pools with deep water at or near one end, multiple outlets should be provided where the width of the pool is more than 20 feet. In such cases outlets should be spaced not more than 20 feet apart, nor more than 10 feet from side walls.

C. Proper pipe connections must be provided in recirculation pools to permit water being drained directly to the sewer, as well as to recirculation pumps. In making connections of pool outlets with sewers proper care must be taken to prevent any possibility of sewage from the building or from outside backing up into the pool.

D. Inlets for fresh or re-purified water should be located to produce as far as possible a uniform circulation of water throughout the entire pool. In semi-artificial pools of irregular shape a careful study should be made of probable circulation currents and inlets located and spaced to provide as complete circulation as possible. All inlets should be located at the shallow water portion of the pool and not more than 1 foot below water line, except in case where reverse circulation is used as discussed in paragraph H.

E. Where the distance across the shallow portion of the pool is more than 20 feet, multiple inlets must be provided, so spaced that each inlet will serve a linear distance of not more than 20 feet. At spoon shaped rectangular pools where the outlets are located more than 5 feet from the end wall, inlets should be placed at both ends of the pool. At large pools with outlets near the center, inlets should be placed at the specified intervals entirely around the perimeter of the pool.

F. In small rectangular pools with only a single inlet and a single outlet, inlet and outlet should be located on a line drawn lengthwise through the center of the pool. Inlet orifices located at or below normal water level should be covered with a grating having openings of at least twice the orifice area.

G. Each inlet should be designed as an orifice and proportioned to supply the volume of water required at that particular point to obtain the best circulation. Inlet piping should be designed to provide at least, twice the area of the inlet orifice. In large pools the inlet pipe system should be designed in sections with gates to permit regulation of the flow to different inlet orifices.

H. In a few cases pools have been designed for fresh water or re-purified water to enter at the deep point and overflow through outlets or skim gutters in the shallow portion. It is believed there may be some advantage in having flow through the pool in this direction, thus permitting floating matters and dirtier waters from the more crowded shallow area to be carried off more rapidly. The committee suggests that in designing piping systems for recirculation or flowing through pools, cross-connections be provided so that flow through the pool may be in the direction which experiments may prove most
desirable. It is also suggested that the question of having skim qutters serve as overflows and outlets in recirculation or flowing through systems be studied more carefully, as it appears that such design may have certain material advantages.

Can you imagine that? it's concise, it's accurate, and best - it does not conflict with the know physical laws of fluids. Oh yeah, this was a day when circulation systems were circulation systems and a drain....was a drain.

Just imagine if we built pools like this today? How did we get the 80/20, 60/40, 50/50 nonsense mandates? Where did we forget what was happening and why? These are all the questions I have and I am spending some time digging in to find out. Pools were SAFER by these design standards than they are today. When you think of something new, like ANSI/APSP-7 and know how many PAGES are included to deal with drains only to find out that we could eliminate ALL submerged suction like they did at the turn of last century.

As you may have seen in Solutions for Suction Entrapment forum on PGN, we recently had a debate and I offered what I believed to be a simple thought experiment. Take a 100 ft x 85 ft x 4.5 ft (ave) public pool. Its 286,130 gallons. A 6 hour turn would yield 800 GPM, which can be handled (volume) by a single 18 x 18 drain cover that has been tested to ASME A112 19.8 (2007) as SAFE as a single suction.

So let's propose the following question: Assuming ALL flow is going to the drain for this particular pool, what are the chances that debris on the floor will find it? Before you answer, consider that the drain has an area on the floor of 2.5 sqft and the pool is more than 8500 sqft (did not include the slope).

We all know that a drain is going to have little influence on dead spots some 100 or more feet away, it doesn't have significant effect at ELEVEN INCHES. What is also suspiciously missing is any nonsense about "circular motion of the water." In fact, the writers went to great lengths to attempt to create "plug flow" where drains WERE used. They put LIMITS on where the returns would be to encourage the water to flow towards the pool - entraining dirty water on the way to the drain. It was a North American standard so they did not consider coriolis effect and toilets flushing in Australia either. [Side note: if you think the rotation of the earth has an effect - read this].

I find it amazing that not only is this language COMPLETELY accurate AND concise, it counters MOST if not all of the folklore that plagues our industry today. Antidotal evidence of cloudy pools associated with no drains, etc...don't really stand up when one actually goes out and measures what is going on - there are always other explanations. I don't want anyone to feel embarrassed by the blatant statements that go counter to what you are taught. While this is important, in the grand scheme of construction schedules, plaster, steel, gravel, tile, piping, can you save my sod...and the prized butterfly bush you just demolished, knowing the details and physics behind circulation is really a LOW priority. One can't really do much with it in the field and we are working now to include some of the basic guidelines in our next generation standards.

What I do have a problem with, especially in light of someone's husband, daughter, son, grand daughter, etc...dying, is the complete unwillingness to LEARN. Folks, this is not debatable with any merit. There is not one person that is actually competent in fluid flow that would argue this point.

Drains don't move water, inlets do. It's really that simple. Drains can be used to RECEIVE water, but as we can see from our well thought out standards of yesterday, it's going to be difficult with the type of pools we build today and most of our standards would not let us BUILD the pools above - they were right then, we are wrong now.

Benjamin Franklin's first TWO patents were swimming devices and he also wrote a book on swimming once said,

"Being ignorant is not so much a shame, as being unwilling to learn."

Nothing could be further than the truth.

Early Thoughts on entrapment

Tue, 19 May 2009 12:47:47 -0500

The Virginia Graeme Baker Pool and Spa Safety Act is in full swing and Pools across the country will once again, become safe...right? As it turns out, it’s really not that easy. While creators and sponsors of this legislation were really trying save lives, an unintended consequence resulted. Today, millions of dollars are being wasted by throwing the proverbial “good money after bad.” Many of our Health departments, state pool codes, and even legislative processes attempting to “do good” are pressing on the economy of public pools when funding for these facilities is at an all time low. We are well beyond the day of Buster Crabb, Ester WIlliams, and Johnny Weismuller. Swimming will see a bit of a rise, with the phenomenal performance of Olympic Champion, Michael Phelps, but there once was a time when swimming was one of the top ten most popular activities.

I hope it comes back.

No one wants children to die in swimming pools. No one wants people to get sick in swimming pools. We repaired Hubble Space Telescope this week, surely we can stop entrapment. As it turns out, the solution to this issue is really nothing new and the very sad part is that public pool codes in 1928 were actually better in many ways than they are today. I really don’t know of another single industry where I might say that. We are not just joking and saying less regulation is better; what is irrefutable is that our pools were actually SAFER using building practices in 1928, than what states are legislating and mandating all over the country today.

First, let’s review an actual entrapment case I recently found:

Held for Girl’s Death

Harry H. Bond Jr., well-known sanitary engineer, and member of the A.S.S.E. and A.S.M.E., has just sent us the following newspaper clipping:

Maxwell Berk, manager of the Ostend pool in Far Rockaway, Queens, was arraigned on a technical charge of homocide in Far Rockaway court yesterday in in connection with the drowning in the pool last summer of Helen Flynn, 18.
Miss Flynn, who lived in Rockaway Beach, was sucked under by the suction from an open drain and was drowned before lifeguards could reach her.
Magistrate Frank J. Giorgio released Berk in $5000 bail pending the actions of the grand jury.
This is a warning to all pool operators. Certainly Mr. Berk would give much to bring this girl back to life, but, unfortunately this is nothing that can be done in the way of restoration.
If in addition to these efforts in the interest of a clean pool the water is sterilized by some recognized system of sterilization, there need be no concern as to the quality of the water in the pool.
All pool operators, however, can prevent a like tragedy. They should not, under any circumstances, permit a drain to be opened until the pool has been closed to patrons. And the guards should inspect the premises to make sure that ALL are at a safe distance from the pool.
Drownings in swimming pools are very, very few. But even the few must be eliminated.

- January 1930

Can you believe this? nearly 79 years to the DAY, that Kiah Milsom was killed in a tragic death in a Kentucky pool with an unnecessary drain, we find pool operators being instructed to never “open a drain” unless bathers are at a safe distance from the pool.

Ironically, I found this article by accident while researching pool codes at the turn of the century. After nearly a decade in this industry, there are still many scientifically unsubstantiated requirements in state pool codes and no one really seems to know how, or cares, about where these rules came from. What absolutely floored me was that pool codes about circulation were more correct in 1928 than they are today.

A New Year for Safety

Thu, 1 Jan 2009 07:20:27 -0600

As cliché as it may sound, where did 2008 go? It was certainly a fast-paced year and extremely busy in terms of swimming pool and spa safety. In some sense, using a child analogy, it’s as if we stepped out of industry adolescence and jumped right into the frenzy of college freshman mayhem. Perhaps not all of you gained too much weight...

The state of our industry from a safety perspective is actually quite good. While we all felt the pinch of the economic downturn, these times tend to have a culling effect and in some ironic twist, many of those that fail, didn’t need to be around in the first place. 2009 will provide some interesting challenges for us as we now try to take a collection of “consensus” derived rules and laws, and turn them into understandable, repeatable, operational practices for our companies.   This will involve CHANGE and change is never easy.

There will be those that say we went too far, and perhaps we did. There will be those that say we haven’t done enough, and maybe we haven’t. There will be a lot of comments, but there is only one test that in the end will really matter:

Are the rules, standards, and codes we have put into place technically accurate and based on sound science and engineering principles?

That is the test. It is this very action that will ultimately decide if the thousands of hours of volunteer work, the millions spent collectively by distributors, manufacturers , and pool builders, both in cash and opportunity cost, will actually save a life. While there is no way to put a price on any life, certainly there is a way to put a face on it. I can assure you if any of the faces down the right side of this page...Alexia, Erin, or Danner Cronise were on that list, the outrage and dedication everyone has come to expect from me would be but a small shadow of what would happen. That being said, every word of suggested improvement I offered would be first challenged by the scientific method of Observation, Hypothesis, Prediction, and Testing. Our industry is way past “daddy-did-it engineering.” It matters not how long you have been in business - some have 30 years of experience and others have one year of experience 30 times.

Our collective dedication to safety has angered a few, created excitement in other, and most importantly - I know we have saved a life. We never hear about those that didn’t drown, but I can be sure that not one suction entrapment has or will occur on a pool without submerged suction. I know of no reported cases of cryptosporidium, E. coli, giardia, or legionellosis traced back to pools with no drain. In fact, I suspect most of pools with these reported health issues had a drain as these problems are more commonly associated with public pools.

If you want to learn more about Recreational Water Illness, you can find some fantastic fact sheets at the NSPF website. At this point it is just a matter of time and these legacy devices will be displaced by safe, overflow alternatives. Until then, we will still have to build submerged suctions in our pool safely, with correct covers, properly sized piping and pumps, and following the ANSI/APSP-7 Suction Entrapment Avoidance Standard. Finally we will all want to verify, as a matter of standard industry practice, that what we install IS and REMAINS operational and safe - this is no different that testing the water for chlorine. The new ASSP-7 Field Verification Addendum will give us these tools.

While we have spent countless hours and industry resources on this important, but single issue over the last 5-6 years, each year more children die through preventable drowning that ALL ENTRAPMENT CASES OVER THE LAST 20 years combined! The U.S. CPSC estimates there are about 260 drowning deaths of children under 5 each year in swimming pools. Suction Entrapment related injury or death is relatively rare. Many more drowning deaths (thousands) happen in natural bodies of water, but there never seems to be any real rush to fence and install alarms on all the rivers, ponds, oceans, and lakes. I’m not making light of this very real safety issue, I am pointing out that our actions are a reflection of our values and many more hours are going into a small percentage of the problem. Perhaps we should all reconsider.

Rather than continue down this divisive, contentious legislative path, what can WE do collectively in 2009, as both a construction and safety industry, to continue to build the pools and beautiful water features our customers are demanding? How can we come together on these issue and be certain that our customers are aware that “children aren’t waterproof?” How do we promote the pioneering work of Dr. Harvey Barnett and make sure more of our customers teach their children to swim? What can we do to improve our understanding of circulation in swimming pools and remove the myth that a drain or some arbitrary 80/20 skimmer/main drain flow split is going to assure proper distribution of sanitizer?

There are so many ways our industry can make positive changes and all of them start with an awareness of facts around pool injuries and deaths followed by a focus on sound scientifically validated solutions. To succeed we MUST move beyond our our safety product-driven legislative habits and onto solving the problems one by one. Yes, selling plastic can be lucrative, but selling pools and lifestyle is so much MORE profitable and meaningful.

Don’t we all remember the story of Thomas Edison and the Phonograph? Remember the notebook in which he wrote every possible problem and then one by one he checked them off?

• Cracking Sounds
• Knocking Sounds
• Humming Sounds
• Chips in Wax Cylinder
• Low Recording Time

• "That’s just where your trouble has been. You have tried only reasonable things. Reasonable things never work. Thank God you can’t think up any more reasonable things, so you’ll have to begin thinking up unreasonable things to try, and now you’ll hit the solution in no time."
• -- Thomas Edison

Why don’t we take that approach in our industry? We are hindered in our efforts for increased safety by special interests and fear of change - our problems are not particularly difficult to address. It’s NOT rocket science - we are just trying to keep pool water clean and healthy and design structures that are both aesthetically appealing, but safe.

To the Pool Builder, Service Tech, Retailer and Manufacturer - Do what is right, whether it is legislated or not. Stop resisting change and understand that new innovations and ideas will continue to make your business THRIVE. Safety is a great SALES TOOL that creates a win-win for you and your customer! As well, the job is not complete when you receive the final check - it is when your customer knows how to operate equipment and maintain a safe environment. What if your last visit for "pool school" were as enthusiastic and exciting as when you were trying to sign the contract? Think about it.

To the Safety Advocates - Help us all make consumers aware of preventable drowning accidents, but understand we will never achieve 0 death rate. Even if we fill in EVERY pool, the drownings will still number in the thousands every year in natural bodies of water. Let’s join forces to use our limited resources to educate pool owners, and their neighbors, on ways to prevent these avoidable drowning deaths and continue to allow them build beautiful pools. Help encourage ALL STATES to require certification to operate a public pool. Many peoples lives are at risk from RWI and other issues, and yet only 20 states require some type of Pool Operator Certification for public pools. This must be changed.

To the State Health and Building Officials - Be sure your laws/codes are based on sound science and engineering. We all understand that many offices are understaffed/underfunded. Your jobs are not often appreciated by everyone; however, don't let tradition and habit get in the way of safety progress. Like every positive improvement in each of our lives, progress necessitates change and your codes are no different - they must change. The Virginia Graeme Baker Pool and Spa Safety Act allows various options for a wide range of system configurations. Join the APSP, U.S. CPSC, CDC, NSPF, and many more in promoting: ALL States. All Options. Don't cave into those that pedal fear over fact. Emotionally based decisions are where most mistakes are made. See above note on Public Pool Operator Certification.

In close, I would like to see my children, and all children, live out the great life of my grandmother, Marie Cronise, who died in October 2008 only 5 days after this picture was taken. She lived a full life (incidentally hated water), but every child or adult that dies in a pool should be so lucky. We won’t make pools perfectly safe, but we have a lot of room for improvement.

Let’s make a great effort in 2009 for Swimming Pool Safety! If I can help in any way, don’t hesitate to email or call.

Ray

.

December 19, 2008

Fri, 19 Dec 2008 08:30:11 -0600

The day is finally here. It is the day when the Virginia Graeme Baker Pool and Spa Safety Act (VGBA) is finally in full effect. Under that act, there are a number of options, but all of them require that either the drains be removed, or a new suction fitting, one tested to ASME A122.19.8-2007, be installed. If they are single outlets, then one must choose from one of 4 back up options:

• (I) SAFETY VACUUM RELEASE SYSTEM.—A safety vacuum release system which ceases operation of H. R. 6—305 the pump, reverses the circulation flow, or otherwise provides a vacuum release at a suction outlet when a blockage is detected, that has been tested by an independent third party and found to conform to ASME/ANSI standard A112.19.17 or ASTM standard F2387.
• (II) SUCTION-LIMITING VENT SYSTEM.—A suction-limiting vent system with a tamper- resistant atmospheric opening.
• (III) GRAVITY DRAINAGE SYSTEM.—A gravity drainage system that utilizes a collector tank.
• (IV) AUTOMATIC PUMP SHUT-OFF SYSTEM.—An automatic pump shut-off system.

..and two more

• (V) DRAIN DISABLEMENT.—A device or system that disables the drain.
• (VI) OTHER SYSTEMS.—Any other system determined by the Commission to be equally effective as, or better than, the systems described in subclauses (I) through (V) of this clause at preventing or eliminating the risk of injury or death associated with pool drainage systems.

Wait - that Federal clearly list 6 options and yet up above I’ve clearly stated there are only 4 backup options; is this just a simple oversight?

As it turns out, Drain Disablement is hardly a “backup” for a single drain - it ELIMINATES the hazard completely. It should be obvious, but a child cannot get stuck on a drain that is not there. The APSP/ANSI-7 standard, the 2009 ICC code, the U.S. CPSC and the CDC all get it, For example download the CPSC guideline for compliance and Note:

CPSC staff recommends that to ELIMINATE and not just MITIGATE the drain entrapment hazard in pools and spas, pool owners should disable old drains or build new pools without any drains and use gutters, overflows and/or skimmers to provide water to the pump.

I don’t think I could have written it better myself. Congratulations, now lets see what the states do with it in the complete VACUUM of any scientific proof that a pool requires a drain for proper circulation. Most state codes actually mandate return inlets for circulation and drains, to drain a pool. There are much safer, more effective, and faster ways to drain a pool than using a potential hazard. As well, WaterShapes Magazine recently published this article, Considering and Option.

Ok, I’m a bit partial to the content.

The sixth option is nothing more than a legal, catch all CYA. True, there are some fantastic health departments and building departments that will work with you on alternatives, but most simple say, no. Come now, state are saying NO to option (V) that is Printed IN THE FEDERAL LAW, what do we expect from some “other system” with no clear performance language. The Other systems option, while well intentioned, is meaningless. Case in point, REMOVING the drain is clearly BETTER than backing one up (no drain = no hazard) and yet many states purposefully outlaw this particular option.

No, there are really only 4 backups for a single outlet. Items (I) - (IV) are backups to single outlets. The problem created here is that each of these is a back up for the same hazard: Body Entrapment. What about the other 4 entrapment hazards, which combined injured and killed the majority of the victims to date? Does anyone care about backing up those entrapment potentials? What backup device is out there for Hair or Evisceration or Limb?

Recall, there are 5 types of entrapment found when one reviews the epidemiological cases reported to the US Consumer Product’s Safety Commission:

• Hair Entrapment - I like to call it entanglement, because it gives you a better picture of what is happening. Hair is pulled through the opening of a cover or grate and then it tangles in a knot because of the rapid water flow and the victim drowns.

Body Entrapment - This is what you most commonly imagine when suction entrapment. Remember the vacuum and bowling ball? Insert that image here. VGBA “backup” options are all aimed at this target.

Limb Entrapment - This is how the Kentucky Teen died last week, and what’s important about the recent Connecticut manslaughter case. Note that water is moving up to 6 feet per second (4 mph) in the pipe - many pools exceed this flow rate. You get too close to an uncovered drain and suddenly your hand or foot becomes entrained in the water flow. In just 0.25 seconds, the time to blink an eye, you are hammered 1.5 feet into the pipe. Similar to chinese handcuffs (and wedding bands), it’s a lot easier to put pipes on them on than take them off. and in this particular case, the PUMP WASN’T running as the pool was DRAINED.

Evisceration - Disembowelment - typically a small child trying to urinate or defecate over an unprotected suction port (thinking that is the right thing to do) or just being a curious kid. After sealing off the outlet, it is identical to limb entrapment, but substitute intestines for arms. it is gruesome and exactly what happened to Abigail Taylor in a wading pool on an unnecessary drain.

Mechanical - In 2002 when first sifting through epidemiological reports collected by the U.S. CPSC, I found that most fit into one of the four categories above. There were a few odd ones - jewelry, bathing suits, etc.. and so we created this other catch-all group. Until we can find a new underlying physical cause they end up in the Mechanical category.

And what is the unspoken, or perhaps a whisper, in the Media Coverage and the hype is that only ONE of these 5 hazards is addressed with the back up options offered. In fact, the law is really being distilled down to many in the industry as a “plastic swapping frenzy” where two nuts and a truck (and a the mystical tool that removes covers in all standards) are out swapping out covers, with no knowledge of flow rates, no knowledge of the piping issues connecting the drains, no knowledge of the attachments (part of the law per ASME A112.19.8-2007), and no knowledge of the required sump configurations.

It is nothing short of a plastic-fest and there is a LOT of money being made on this and very little consideration, press, or training given to selecting the CORRECT cover where the outlet is necessary, and elimination where the drain is unnecessary (majority of the installations). Even some of the most responsible, well intentioned pool builders are headed into the field every day not understanding what they are doing could be potentially INCREASING a the risk of the hazard.

The CPSC, NSPF, APSP, and select other Manufacturers are working hard at getting the message out, but building a pool with drains is complicated and worse, when you do it correctly (to the standard) it goes against YEARS of industry tradition and generally accepted building practice.

And when one takes the time to actually read through those epidemiological cases reported to the US CPSC one will find that the three REAL causes are:

1) pools not built to standard
2) pools not maintained to standard
1) pools modified after the fact not to meet standard

With no ill-attention at all, the VGBA is causing an environment, a deadline, in an undereducated community, where the opportunity DOES NOT exist for all options given to us in the federal law and is encouraging those not properly trained or certified to “replace covers and install backups.” This will likely result in a complete exacerbation of these three underlying causes reported in the reports of death and injury cases to the CPSC.

So if you are installing new covers, make sure you KNOW THE FLOW RATE and choose appropriately rated covers. Make sure the manufacturer has specified that cover for the sump you are replacing - it makes a difference. Be sure to review ANSI/APSP-7 to be certain pipe sizing and spacing between the sumps is correct. Make sure that the ATTACHMENTS were tested with the cover you are installing - putting new screws into a stripped sump does no one any good. Check to see whether or not you can just ELIMINATE the submerged suction outlet all together, by taking water from the skimmers or gutters.

Finally challenge ANY state that MANDATES a Hazard and then mandates a backup - it is plain and simple technical ignorance and clearly contradicts the options given to us by VGBA. There has never been any scientific study supporting drain mandates for circulation are necessary. Our safety message regarding VGBA should be clear:

ALL STATES. ALL OPTION.

Few get it - yet. There is a lot of product to sell, lots of systems to backup, lots of plastic to swap, and the real safety message doesn’t fit well into sound bite media or short term profits.

Eventually, there will be a tragic case. A death caused by a new piece of plastic that was broken or missing, a screw in a stripped sump, or a backup device that was improperly installed. Time will tell whether or not we ask ourselves that fundamental question:

Is a drain necessary on this pool?

If the answer is yes, then we install a properly rated suction fitting per ANSI/APSP-7 and verify it is working. If the answer is NO, then we remove the drain or build the pool without one.

.

Do you have the correct drain Cover?

Fri, 31 Oct 2008 07:34:13 -0500

As many of you know, I am often hailed as the “no main drain guy,” because for the last 6 years I have been pushing for the option (not the mandate) to build pools without a drain. You can read more about this concept in the November 2008 WaterShapes Magazine. If you want the full technical scoop, you can download it here. I still believe that many pool drains can be eliminated and completely remove the hazards of suction entrapment.

For now, I want to talk to you about pools that HAVE drains or existing covers you may have to replace due to the Virginia Graeme Baker Pool and Spa Safety Act. Our industry is under mandate to replace all public pool drain covers by December 19, 2008 or the first day the pool is open after the next season. These new covers must be tested to an updated National Standard: ASME:A112.19.8(2007). This standard was a significant upgrade in safety from the previous cover standard. It added three very important testing components: Full Head of Hair, Body Block, and Material UV tests.

These tests are all designed to make sure that the cover is not only safe, but that it will remain in tact. Most accidents happened because covers become broken or missing for a plurality of reasons. The U.S. Consumer Products Safety Commission is the enforcer of this particular congressional act and has come up with a standard label to place on all of these cover “VGB 2008” by designation of this letter.

On the residential side, the CPSC will disallow the sale of covers that do not meet the the new standard. This will slowly eliminate these covers on existing pools. While there is no mandate to replace the existing covers in residential pools, it is a good idea for safety to do it - whether required by law or not. It's the right thing to do. There will be more information on the legal aspects of this and your responsibility offered by our Pool Genius Adviser Stephen Getzoff in the weeks to come.

Here is one thing that likely no one has told you and it will be VERY important as we replace covers on existing pools. “Suction Outlets” as are being tested in the above ASME standard are defined to include: cover, attaching screws, and the sump. In other words, simply having a cover that’s stamped with “VGB 2008” is not enough - the manufacturer must have specifically tested and specified that this cover is intended to work with your manufactured or field manufactured sump. As well, the screws are the weak link - remember broken or missing covers up above? If you replace an old cover with a new cover, but in the process strip the screws, you have decreased safety, while appearing that you are technically complying. It is imperative to be certain that NO SCREWS are stripped, the cover is SECURELY in place, and the flow rate does not EXCEED that which is printed on the label.

Equally important for field fabricated sumps, you should remember that in the absence of a manufacturers specification, you will need 1.5 x diameter of the pipe underneath, at the center (where the pipe comes through the shell) and 1 diameter at the edge of the grate. We don’t typically plaster in grates with this sort of clearance, but no one is talking about it. Here is a diagram from the ASME standard on field fabricated sumps:

Figure 2 from ASME A112.19.8(2007) ©2007 ASME all rights reserved.

Take a look at this public spa I recently visited. It has at least 4" (maybe 6"?) piping and that appears to be a 12 x 12 flat (it perhaps is a 9 x 9 hard to tell and I did not measure it - if you can identify the cover please add a comment) In any event - exactly what needs to be replaced. Now look at the clearance between the drain cover and the sump - 3.4 inches? It certainly does not meet the 1.5 x diameter called out in the standard. So a cover for this sort of installation would either need to be rated for this shallow clearance or the sump must be modified to meet requirements in the table above.

Example Spa Cover with Field Fabricated Sump - This is a tough call on which cover to use

Finally and most important is to measure the flow rate on your system. This is primarily to ensure hair entanglement protection. Each of the dual outlets must be rated with a number ABOVE the maximum system can flow. If the covers are rated at 125 GPM, and there are 2 drains, you CANNOT flow 250 GPM through the outlets. For dual outlet installs, the maximum flow through the pair is the lowest number printed on the cover. Flow rate can be easily measured in the field and a standard testing protocol should be released in the next 2-3 weeks from the ANSI/APSP-7 committee.

Recently I traveled with several National Award-Winning builders in Florida and visited about a dozen pools. (if any of you chose, please comment). EVERY pool tested had 4-8 times the necessary water for circulation! We were astonished to find out that they had been over pumping pools for this long. We performed a very simple measurement of flow rate (I’ll cover this completely in a later webinar on Pool Genius Network) and it was enlightening to him to say the least. The smallest pump we measured was a ¾ HP and it was producing 75-85 GPM depending on piping configuration. That is not a lot of water, but it was on a 7000 gallon pool or a 1.5 hour turnover! Wonder what those 1 ½ and 2 HP were pushing? I think you get the point.

In closing I want to be certain that you take away two very important thoughts:

1) The pool cover you are servicing MUST be designed to work with the manufactured/field built sump you are replacing in order to meet the standard.

2) The cover must also be rated for the MAXIMUM flow rate on your system. Most pumps are moving a LOT more water than you think. The days of “selling on HP “ are gone and we need to focus on the pumps flow rate, which is tied to the specific piping of the pool. IF you don't measure the flow rate, YOU DON"T KNOW what it is - measure it!

We will cover this subject in much more detail over the upcoming weeks. Until then, let's all keep swimming pool safety at the forefront of our business and the industry.

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A victory at the ICC

Mon, 22 Sep 2008 07:01:23 -0500

In a decisive victory for swimming pool safety, the ICC overturned its outdated and dangerous “Appendix-G” code that has plagued municipalities across the country. Now, the ANSI-Consensus APSP-7 Standard for suction entrapment will become the new basis for the the 2009 code. The International Code Council writes uniform building codes that have been adopted by municipalities and state governments across the country.

Most of the arguments against the APSP-7 code have been heard time and time again. The “consensus process” was invoked by opponents on many other standards to give credibility and credence, but the same process was somehow “disallowed” by these same opponents when applied to APSP-7. In one particular debate, Gary Duren of Code Compliance said that his proposed language did not address evisceration and this form of entrapment is specifically excluded from the scope (this is true of both the ASTM and ASME SVRS standards).

We couldn’t agree more with Mr Duren about the standards he leads and represents, but where he totally missed the point is that APSP-7 DOES allow us to address this form of entrapment, which was responsible for the death of Abigail Taylor in MN, by simply eliminating the drain. In fact, not only does APSP-7 include the two standards Mr, Duren and other advocates want mandated on every pool, it also allows pools to be built WITHOUT a hazard in place - no main drain, which is supported by the 2007 Federal Baker Act. APSP-7 is a standard based on preventing entrapment, not mitigation the issue. What the opponents have argued for is a series of “catch and release” devices. Current vacuum release standards allow 4 seconds of HIGH VACUUM exposure before the victim is released. That is high when we compare a limb or evisceration happens in just .25 seconds - the time it takes to blink an eye. Many devices claim faster response time, but the same individuals sit on the standards writing committees won’t move the reaction time - truth is in action, not public debate.

IF one’s drain cover is in place, the flow rate is correct, and it has been properly tested, you are safe. If it is not in place, you are UNSAFE - regardless of any secondary, or now, tertiary (third layer for only one form of entrapment). It was interesting that at least one presenter, that knows better, called for this “tertiary layer” even though he ignored the other 4 forms of entrapment. I think finally self serving business efforts are starting to be seen and collapse.

As Mr. Johnson succinctly pointed out, “No Drain = No Hazard and elimination trumps mitigation every time.” Loraine Ross and Jennifer Hatfield also added critical testimony about both Florida’s early adoption of APSP-7 and steps are underway to eliminate drain mandates in public pools in that state as well. Ms Ross was also clear that the same arguments against APSP-7 had been heard time after time by National ANSI review and were always rejected.

Carvin DiGiovani, of the ASPP Government Affairs was also present and was very vocal about how diligent the APSP-7 approval process has been. It has been scrutinized by more individuals and come under more technical eyes than any standard the APSP has ever released. There has been significant testing and verification of this standard and that helped the writing committee get it right the first time. As well, there will be even more improvements in the future that will update and solidify any remaining criticism.

Steve Barnes gave a power presentation about the ability to build pools without main drains. During rebuttal from Mr. Duren about the issues involving UV testing protocol changes and the new addenda A to ASME A112.19.8-2007, which Mr. Duren insisted that we “do nothing and wait until this all resolves itself,” Mr. Barnes stood up and quipped, “we have a drain cover at Pentair that passes the UV standard, so its not impossible.” For the record, it was Gary Duren that held up the addenda for ASME A112.19.8-2007 with administrative procedures or it would have been passed and implemented in April 2008. Nice try, Gary.

So what is the next step? We need to get states across the nations to remove drain mandates in public pools and begin the educational process on APSP-7 and inspection.

In my next blog I will deal with the issue of drain cover replacement as a single solution. It’s not quite as easy as a few screws and a piece of plastic.

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Proving the Obvious

Wed, 20 Aug 2008 08:37:03 -0500

I went to college with a friend, Val Byler, who was raised in an Amish family. He was fascinated by the moon, stars, and planets. He was not allowed to pursue technology. I can’t imagine leaving my family in order to study science or to follow a passion and career in space.   Val told me of nights when he would sneak out to a secret field, where he and some of his friends kept a beat up old car they bought, and would drive it in circles for fun. He lay awake at night and watch the stars for hours on end and regretted the little sleep when morning chore time arrived.

His first thoughts were that the “night sky” was a giant sheet over the earth. He envisioned that the stars were just holes in this sheet and the sun was shining through like tiny leaks of light.

You probably aren’t buying Val’s view of the universe, but how could you prove it to him if he didn’t have the desire or motivation to learn? If that is what he had been told all of his life, how do you convince him what he believes to be true isn’t supported by fact or science? Especially if he choses to turn a blind eye to both?

We find ourselves in a similar situation with some Health Departments, particularly Kentucky, on the ideas behind pool circulation. As explained in previous blogs, water exits the pool through an “outlet” is filtered and sanitized and returns to the pool through an “inlet.”

Inlets distribute the clean water and sanitizer throughout the pool in much the same way as vents distribute heated and cooled air throughout your home. Fluids can only be pushed...they cannot be pulled. Hence, if one wants to get water out of a bucket, you can’t reach in and pull some out, you have to in fact splash, or push it out with your hand.

There are two types of swimming pool outlets: skimmers and drains. Skimmers remove material floating on the surface and drains are used to make up for water flow above and beyond that provided by a skimmer. One may also empty the pool using a drain. In many states, including Kentucky, when skimmers are place in the pool as prescribed by code (by pool surface area square footage), there is automatically enough water for the pump to properly circulate the pool for the desired 6 hour turnover.

In other words, in most pools, including the pool that Kiah’s accident happened in, drains are not required for circulation. It is common industry practice to use a sump pump to drain the pool (see side photos). For a year prior to this accident, the state was requested to allow a public pool built without a drain; we knew there was enough water from skimmers to properly feed the pump. We proved it over and over to the state. It was denied. After the accident, the state continues to needlessly dig in on this point, and incredulously, has even now gone to the CDC for backup.

In The News

Let’s take a look at what the state has said publicly in a recent news story:

Some health department officials aren't convinced that removing drains is the answer, and are concerned about whether pools would stay clean and sanitary without drains.
”We're certainly not opposed to it, but we do want to see some factual evidence and sound research,“ said Guy Delius, acting director for the Division of Public Health Protection and Safety in Frankfort.
He said there are a wide array of communicable illnesses that can be passed through water. Delius said the department is open to discussing new technology and ideas with anyone. But the ideas need to be backed up by sound research, possibly by universities or private firms, before they're implemented because they can affect hundreds of people in a pool.

Any attempt to discuss with the state whether or not we can eliminate a drain is met with the same mantra: everyone does it and we haven’t see the independent science to prove a pool will operate without it. They don’t know, we don’t know, we are not sure, are all great phrases government bureaucrats like to use to obfuscate the issue. Like coupons and rebates, they are hoping if situation is made complicated enough, people and media will grow bored with the issue and go away.

This time in the middle of the debate a 14 year old girl, Kiah Milsom, died as a result of this incompetency. The issue is not going away.
 We haven’t seen the science? The fact remains, the STATE cannot produce one paper or study that concludes a pool NEEDS a drain and refuses to consider at anything presented contrary. On the material that is presented, they will say, it is not independent. While this should not require anything other than simple explanation, independent tests were completed years ago and the state has this information, but choses to dodge the obvious.

Have You Read the Kentucky Swimming Pool Code?

So why not take a look at what Kentucky State Swimming Pool Code has to say about circulation? You can download it all and read it for yourself. I have saved you some effort, so let’s cut to the quick.

Recall our argument with the state: outlets (drains and skimmers) provide water to the pump and INLETS circulate the pool and distribute sanitizer. WHEN skimmers provide enough water, drains can be eliminated to take entrapment hazard to ZERO. No drain = No hazard. Pools can and typically ARE drained with sump pumps. Sump pumps are not equal in value to a human life.

Kentucky Code:

(8) Outlets.
(a) All facilities shall be provided with a main outlet at the deepest point to permit the facility to be completely and easily drained.

(7) Inlets.
      (a) Each inlet shall be flow adjustable.
     (b) The velocity of flow through any inlet orifice shall be in the range of five (5) to twenty (20) feet per second, except in facilities equipped with skimmers it shall be in the range of ten (10) to twenty (20) feet per second.
   (c) Inlets shall be located and permanently directed to produce uniform circulation of water to facilitate the maintenance of a uniform disinfectant residual throughout the entire facility without the existence of dead spots.

... (e) Inlets for wading pools, and small spas for six (6) or less bathers, shall be at least two (2) in number, and placed so as to meet the requirements of paragraph (c) of this subsection.
      (f) At least one (1) inlet shall be located in each recessed stairwell or other space where water circulation might be impaired.

Now, that seems odd. Not only does Kentucky state code completely MATCH the science we presented to the state, it specifically states that when we there is the chance of a dead spot, an INLET is added, not another main drain.

In fact, like all National ANSI pool codes, as the pool size increases, we must add more inlets and more skimmers to accommodate skimming and circulation. But no matter HOW large a pool is, we only require one (now two) drains at the “deepest point of the pool.” This dates back to the earliest pools, drain and fills, which were drained often and filled with clean, fresh water. These type of pools continue to operate in some locations and have caused deleterious water conditions and associated health issues. When industry moved to chlorine based sanitizing systems with filters and recirculated the water, drains were used periodically, to well, drain the pool for maintenance.
 Today, we can buy a submergible sump pump or a portable deck pump that can drain the pool in a fraction of the time it takes for a circulating pump to drain the same pool. These are powerful pumps we wouldn’t want running when bathers are present.

So despite the rhetoric and the obstinate attitude among Kentucky State Health officials on this very simple issue, they refuse to act and allow ALL OPTIONS of the Virginia Graeme Baker Pool and Spa Safety Act to be used in the State of Kentucky. We are not asking to do something new or different, just asking to have the right, a right given to all states by federal legislation and supported by all National ANSI consensus swimming pool standards, to build a pool without a drain or disable one that is dangerous and many times not properly maintained. A right to build a pool with a circulation system that operates exactly how state code says it operates.

Keep in mind that according to the Aquatic Safety Research Group, Kentucky is one of the many states that doesn’t have any pool operator training requirements for people operating or maintaining a public pool.

A Solution with ALL Options

Why must we be forced to this level of indignation to get any state public servant to listen? It is frustrating, but if one wants to save lives from these rare and tragic accidents one must recognize it is HUMAN ERROR that has caused nearly every reported suction entrapment accident. Isn’t this a simple request?

All States. All Options.

Val Byler finished his degree in physics and became a Scientist at NASA’s Marshall Space Flight Center in Huntsville Alabama. He is still an avid astronomer. When he visits his Amish family, he is not allowed in the house and has to sleep in the barn. His family still doesn’t believe man landed on the moon and they likely won’t read this blog.

For safety’s sake, It is my sincere hope someone in the Kentucky Health Department does read it.

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Becoming an Olympic Champion

Wed, 13 Aug 2008 19:10:44 -0500

If you are a swimmer, there is nothing better than the Olympics. While many other sports popular in the U.S. are big money - football, basketball, or baseball, for the most part Americans don’t know swimmers.

Maybe they have heard of Wheaties and Mark Spitz.

The Olympic Games is the only place a swimmer can get mega-visibility and this year is a great example; we have Michael Phelps. There have never been more records shattered. This is in part to some amazing technology - a series of revolutionary swimming “skins” developed using advanced computer modeling.

This engineering discipline is called Computational Fluid Dynamics, or CFD and one of the leaders in CFD software is FLUENT (Ansys). The LZR Pulse is an amazing work of engineering made possible by great advances in computer technology and blazing fast processors crunching for weeks on calculations.

What does this CFD Swim suit research have to do with a Blog on Suction Entrapment? The short answer is it could have saved at least two lives: Abigail Taylor and Kiah Milsom.

Joining forces with Fluent in 2004 we decided to use the same technology to show that drains are not necessary for proper swimming pool circulation. The most difficult part about starting the project was convincing Fluent it was worth the effort - not because of saving lives, but rather that every computational fluid dynamist I spoke with thought just like me. It is obvious that the drain is not necessary. Why do we need to hit a fly with the proverbial sledgehammer?

The answer, regrettably, is that it is not obvious to health departments and pool builders across the country. Really, this is not rocket science, but our Pool and Spa Safety codes have not been historically built on science; many are built on tradition and “daddy did-it” engineering. While there has been some strong scientific work on sanitizer efficacy on microbiological contaminants to make water safe, very few people understand the basics of moving water or circulation. Even worse - they are not willing to listen.

While there has been a real push in the last 6-7 years by industry trade associations to push science and engineering based standards, their efforts are mostly met with heavy skepticism by regulators as construction trade at large is rampant with “require my product” attempts. As has been discussed elsewhere in this blog, this is common among makers of drain backup technology.

For nearly one year prior to Kiah’s entrapment on a swimming pool drain in a Kentucky Public Pool, I had conference calls and emails with State Health Officials and they refused to consider pools built without drains. I wrote them after the Virginia Graeme Baker Pool and Spa Safety Act was signed into law (which allows for drainless pools and drain disablement) and they would not consider it.

Then, the news came about Kiah, I immediately felt an outrage. How might I feel if my girl died on a drain that served ABSOLUTELY no purpose in the pool? Who is going to speak up for her parents?

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Lessons From my First Teenager

Thu, 7 Aug 2008 08:51:49 -0500

Tomorrow, my oldest daughter turns 13.

08-08-08.

That is pretty amazing and she is an amazing daughter. She has a great mind, is staying reasonably “on track” in life, and she is a great “people-person.” About 3 weeks ago, I fulfilled my summer promise to take her with me to work one day. She likes hanging out and we had a great time. On this day, we were testing drain covers to the new ASME cover standard. This new standard, released in late 2007, has added significant safety margin to drain covers. It added a simulated body-block test and a “full head of hair” test.

In the first test, a large foam covered block is placed over a running drain. If it takes more than a certain force to pull it off, the cover fails. All covers fail at some water flow rate. You slowly increase the flow through the opening until eventually - it sticks and cannot be removed. The second important test is the full head of hair test. Before this was introduced, we only used a small pony tail of hair to test. The idea is that when the hair enters the drain cover, it can tie into a knot, and well, your little teenager drowns. When we added the full head of hair to the test, it made it MUCH harder to pass. Some of the additional hair covers and mats on the drain cover surface and those last few openings - zip - tie knots that would rival the best trained boy scout.

These are two tests that make drain covers much safer, when they are installed properly. The problem is the “when” part of that sentence. You see, the issue is that many times they are NOT installed properly - in other words, they are broken or the screws are missing. Remember the John Edwards quote?

So as my daughter sat on the side of the test tank watching us test drain covers with a wig and mannequin (we call her suicide sally), she blurted out,

“Why are you guys installing drains in the first place?”

You see, for Alex’s 6th grade science fair project, she decided to do an experiment of whether drains were needed to circulate swimming pools. As you can imagine, I certainly didn’t convince her she needed to switch to germinating bean sprouts.

Actually, her experiment was very good. She took two aquarium tanks and placed a pump in between them. As she pumped water from one tank to the other, she measured which one had the best “mixing” or agitation. Her reasoning was that it is the mixing, or movement of water that distributes chlorine (sanitizer) throughout the pool and this is what State Pool codes are after.

The challenge was to measure “mixing” and this is where an neat idea from my NASA past came into play. While I was a microgravity material scientist, we were concerned a lot with very small fluid flows that would interfere with crystal growth, metal alloy formation, and biological science experiments. Right now, astronauts on the space station continue this research. We used to explain these small flows using an experiment anyone can do in their kitchen. (geek alert)

The idea is that salt water is heavier than fresh water. The second part of the idea is that hot water rises, and cold water falls. Here is the fun part. If you mix some salt into water and add food coloring, it is possible to very carefully place it a glass at the bottom of each aquarium. Because the water is cold AND salty, it stays put in the glass. So you can start with a glass of colored water in both tanks, and it is VERY sensitive to any sort of water flow. The slightest stirring and the food coloring goes everywhere.

So, reviewing her experiment, she had two aquariums with water, each with a glass of salty dyed water, and a pump between them. We carefully placed the suction side of the pump over one glass and the return (inlet) side over the glass in the other aquarium. We had two pools - one with just suction, and one with just jets, or returns. It is a perfect test, because one just turns on the pump and observes what happens to the dyed water in each tank. You can look for yourself.

She is alive today. I’m writing this blog; and while the suction side did NOTHING, the return side was so powerful we had to weigh down the glass just to do the experiment. The lesson is very simple. You can’t move water with suction - only with pressure. You have to push (splash) water out of a bucket, you can’t reach in and pull it out. Likewise, drains do not cause water movement, it is the pressure side that does so. Still, most pool builders and health departments will argue about the issue. They have been taught for so long that drains clean pools and circulate water that is like challenging which color is blue.

While they offer up no proof and can’t explain away a simple 6th-grade science project, it typically comes down to a very flawed logical argument:

Clean pools have drains
I am putting a drain in the pool, therefore it will be clean.

There is of course a basic flaw in this logic. Let me use the same argument in a way it will be obvious to everyone:

All dogs have four legs
it has four legs, therefore it is a dog.

There is super-geeky term for this sort of flawed logic called the failure of affirming the consequence. And if you are arguing about four legged animals it is kind of funny. When it is about something that can kill your child, it is a bit more serious.

Pool builders across the country seem to be paralyzed by fear. Many are unwilling to take the time to understand what the underlying problem is with drains and swimming pools (psst, its maintenance and human error). Many have their one way to do this and some “builder-ways” conflict with our own industry standards. To complicate this issue, they will capitulate to the same flawed logic when spewed by health departments and will not stand up to challenge these drain mandate laws - even when drains are not necessary.

To quote one prominent Pool Builder from TODAY -

“ I know for a fact that the majority of commercial pools who are controlled by the health departments would never buy into this as well.”

Now, if you told him the state was going to mandate glass shards on the floor of his pool and then mandate all kids where shoes, he MIGHT challenge it. Unfortunately, he doesn’t hear the argument that way. All he sees is - I don’t know when to use drains and when they are not necessary. What he doesn’t know is they are NEVER necessary for circulation or sanitizing a pool. He has been taught wrong by others in the industry for 50+ years and truly believes he can’t build any pool without them. It is an addiction of sorts and darn near treated like a religion in parts of our industry.

This individual is part of an organization that promotes National ANSI standards for public pools - what does that 2003 standard say on page 12 of the PUBLIC Pool Standard?

Section 12.3.1 A single pump circulation system shall be designed to handle a minimum of 100% of the pool turnover rate through the skimmer.

So if health departments won’t accept it and he doesn’t want to stand up to support these National Consensus Standards, who will?

I will and it appears a growing army of moms and dads just like me that can understand 6th grade science fair projects and don’t think a state should mandate an optional hazard and then further mandate that we then protect kids from it.

Eighteenth Century English Poet Thomas Gray got it right when he wrote:

“Where ignorance is bliss, ‘Tis folly to be wise.’”

So if I have such a strong opinion about drains and their role in swimming pools, why do I not call for the complete OUTLAW of drains? Simple, we do need them. They are necessary for certain water features, infloor cleaning systems, and spillover spas. If pool white goods manufacturers would make high volume overflow systems, even some of these situations could be handled without drains - of course they sell to pool builders not homeowners and so the ignorant bliss just spreads like kudzu on the side of the highway.

During visit to a very large dolphin exhibit I asked the technician about drains in the tank, “we use overflows for all filtration water. Our mammals don’t understand to stay away from drains and it can trap them underwater where they will drown.”

wow, what if we had that sort of respect for mammals of the two-legged type.

My little girl is safe. Tomorrow she will celebrate her 13th birthday and we will have cake and ice cream. We will sing happy birthday, complete with candles. She will do what is natural when she blows those candles out.

Unlike many pool builders and health officials across the country, she understands, she knows EXACTLY, why she can’t suck them out. She also knows why drains in pools should be optional.

I am VERY proud of her.

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