The ANSI Safety Standards
copyright 2003- 2008
The American National Standard For Portable Spas
Even the bolts on your car wheels are made to ANSI standards for safety. Without this organization there would be chaos in the engineering and design world on standardizing the engineering we use. Next time you look up a bolt that holds your car together, you will see the ANSI standard followed.
ANSI is composed of engineers, scientist, insurance consultants and safety experts or at least that is what I was told.
The ANSI American National Standard for Portable Spas was developed with the help of the following organizations: American Insurance Services Group, Akron, Ohio, Department of Public Health, American Red Cross, Applied Safety and Ergonomics, Aquasport/Seasonmaster, Aquarius Pools, Aristech Chemical, Baltimore, Maryland County Department of Public Health, Building Officials & Codes Administrators, California State ó Fresno Public Health, Clark County, Nevada Health District, Contra Costa, California County Health, D.J Technology, Davis County, Utah Health Department, Fairfax County, Virginia Health Department, Fibre Tech, Garrett Liner, Horner Equipment of Florida, International Association of Plumbing & Mechanical Officials, Illinois Department of Public Health, Laporte Water Technology, Lithium Corporation of America, Los Angeles County Public Health Department, National Fire Protection Association, National Safety Council, NSF International, National Swimming Pool Foundation, NYC, New York Department of Building, NYC, New York Bureau of Public Health and Engineering, Oregon State Environmental Health, Reidel Environmental Services. Roanoake, Virginia City Health Department, Sta-Rite Industries, Sunco Pool Company, State of Washington Drinking Water Operations, U.S. Department of Health, U.S. Consumer Product Safety Commission, U.S. HUD ó Construction Standards, Underwriters Laboratories (UL) , University of California ó Berkley, University of Washington School of Public Health, Washoe, Nevada, County Department of Health, Weld, Colorado County of environmental Health, Whatcomb, Washington County Health Department, Witte and Associates, Yale University, School of Medicine, YMCA Fredreick Coundy , MD.
Let's see! Which one of those organizations would you not want to follow for the safety of your spa?
Below is a sample of some of the design
issues I believe are not always being followed and my commentary after
each one. The quotes are from the ANSI American National Standard for
Under Article III of the ANSI/NSPI American National Standard for Portable spas:
I do not consider a shell that is not capable of standing up without the use of foam as "accepted structural engineering practices". I have found that when these spas leak in a cold climate, the foam structure breaks down as the water freezes and presses into the foam. Also as foam ages it breaks down, so the "starting strength" vs. the "ending strength" are two different things.
I have also found that these spas are not safe to work on while finding leaks. I think that OSHA should take a look at this.
The normal procedure for finding leaks in a full foam spa involves crawling under the spa while it is up on blocks, full of water and running, then start digging the foam out, while you follow the water back into the foam. The problem with that is: as you remove the foam you are also removing the structure, thus making the spa unsafe to be underneath. We do no allow our service guys to dig out full foam spas made this way because of the structural weakness of the design.
The only safe way is not the fastest way to find the leak.
I have talked with service people all
across the US and most of them "hate to fix leaks" in these structural
Under Article III of the ANSI/NSPI American National Standard for Portable spas also states:
In order to protect the spas equipment from freezing during a power outage, GFCI or breaker tripping, or any mechanical/electrical failure, the equipment must not be exposed to the cold outside air in any way. The only spas that do that are thermally closed in design. This design also allows the residual heat from the spa water to transfer into the equipment and plumbing area.
So, the only spas with sufficient, designed
in "freeze protection" are thermally closed spas.
Under Article V of the ANSI/NSPI American National Standard for Portable spas also states:
5.0 CIRCULATION SYSTEMS
5.1.1 The system shall be designed to turn over the entire spa water capacity at a minimum of once every hour.
Do the math: A 7 GPM ( maximum) tiny circ
pump in a 500 gallon spa does not turn over the water once every hour.
At 5 GPM it
Under Article VI of the ANSI/NSPI American National Standard for Portable spas also states:
6.1.1 All filter elements, media and other components which require servicing shall be accessible for inspection, removal and repair, and shall be installed in accordance with the filter manufacturers instructions.
Sounds simple enough, but the filter manufacturers guidelines are not being followed. For one thing, a standard of 1 gallon per minute for each square foot of filter fiber has been the standard for a PRESSURE side filter and .75 gallons per minute for each square foot of filter fiber is standard on a SUCTION side filter system. In a commercial pressure filter the standard is about .40 GPM per minute for each square foot of filter fiber.
These are the "engineering" standards expressed by different filter manufacturers.
To recognize a pressure system from a suction side, the suction side has open filter cartridges that you can simply lift out. It is much more convenient for the spa owners. A pressure side filter uses a "canister" to hold the filter and you have to turn off the pump to remove the filter media for cleaning. There is usually a "lock ring" to unscrew and a lid to lift off. If you are a smart spa filter engineer, you will put in a bypass so that when the water volume exceeds the filter media, the pump still functions according to the pump manufacturers instructions. A non bypass filtering system is simply a very poor design.
Placing 60 Square feet of filter fiber on a 60 Gallon per minute pump does not follow these "manufacturers' "instructions."
There are two problems with that design. 1/ as the filters get dirty the jet pressure drops, and 2/ If the filters are not kept very clean, the pump will suffer from some level of inefficient operation, from simply just working too hard, to suffering from cavitation ( water turns to vapor under a high vacuum and literally will beat the pump to death).
If you do not design the filter system around the pump manufacturers' instructions, the pump can be working too hard, and not operating in the most optimal conditions. It can overwork and have a shortened life, by simply working out of normal operating ranges.
In the trade, we talk about the pump's operating in the "sweet spot". That means the water flow, pressure and amp draw is well within the pump manufacturers' parameters ("instructions")
Under Article VIII of the ANSI/NSPI American National Standard for Portable spas also states:
8.0 RETURN INLETS AND SUCTION OUTLETS
8.2.2 A minimum of two (2) suction outlets shall be provided for each pump and the suction outlet system, separated by a minimum of three feet (3) [91.44 cm] or located on two (2) planes; i.e., one (1) on the bottom and one (1) on the vertical wall, or two (2) separate vertical walls. These suction outlets shall be plumbed such that the water is drawn through them simultaneously through a common line to the pump.
This is about a simple as "apple pie". You can change the spices in the pie, but you can't leave out the "apples and the crust". You must, by these rules of safety, separate the suction inlets and have two on each jet pump. The fittings have to be ANSI/NSPI and UL safety suction fittings as well. Read the article on wood tub suctions for more clarification.
12.0 HEATER AND TEMPERATURE REQUIREMENTS
12.3.2 Water Temperature Limiting Controls: Water
temperature limiting controls shall comply with ANSI/UL 1563 "Standard
Hot Tubs, Spas and Associated Equipment". The water temperature
the heater return outlet shall not exceed 122°F [50°C].
This seems pretty straight forward, except that the largest
hot tub manufacture on earth has a thermal high limit switch calibrated
much higher than this. The purpose of the high limit is to
protect, the bathers from super hot water entering the spa vessel from
the heater. If you have a
240 Volt, 6,000 Watt, heaters it is impossible for the water to exit
heater at less than 122 degrees with a tiny circulation pump. So,
you cannot have a 240 volt 6,000 watt heater on many spas according to
safety standard. If the filter clogs up, the little child
on the outlet of the heater in the floor of the spa will have scalded
(the reason for the safety limit in the first place).
When that tiny circulation pump was first used it was on a 115
volt 1500 Watt heater, which is inadequate for cold climates. At
3 GPM they
still had problems with the high limit at 121 degrees tripping.
121 Degree "Hi-Limit Switch" was the standard because it keeps the
below the specified 122 degrees in the ANSI Standard. As the
spas progressed and started using larger heater, this company was left
the dark ages with cold tubs. In order to compete, they started
the same tiny amount of water flow on a 6,000 Watt heater. Some
the early versions had a 151 degree F high limit on the heater.
you ever get a chance, and want to see how hot that is, stick your
in 151 degree F water, and tell me if you could stand it?
Most all of the problems relating to this company is due to
the 100% no bypass filtering and the tiny circ pump, the two major
selling points they use. These spas should be outlawed, until
they conform to the ANSI standard. Any spa that touts a 24 hour
circulation pump, and a 6000 Watt heater, you better check to see what
the circulation rate is. The minimum for safety is 18 gallons per
minute according to my testing. When
you start with a flawed engineering, then try to build on it, it just
worse. Avoid all spas that use a tiny pump, less than 18 gallons
minute on a high Watt heater. That takes care of about 20 brands
I know of, including all the major ones from Southern California.
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