Healthy Water Summit Public Swimming Pools, Spas, and Water Parks June 30, 2009

Transcription

1 Healthy Water Live Webcast Public Swimming Pools, Spas, and Water Parks June 30, :00 am 12:00 pm 1 Healthy Water Live Webcast Public Swimming Pools, Spas, and Water Parks Program Developers This program is provided by the University of South Florida Center for Leadership in Public Health Practice through a grant supplied, in part, by the Public Health Training Center Program, Health Resources and Services Administration, U.S. DHHS. This course was developed in collaboration with the Michigan Public Health Training Center, University of Michigan School of Public Health, Office of Public Health Practice and the Florida Department of Health, Environmental Health Division, Bureau of Water Programs. 2 Healthy Water Live Webcast Public Swimming Pools, Spas, and Water Parks Program Overview 8:05 am Course Introduction 8:15 am Healthy Swimming Pool Water 9:15 am Waterborne Disease Epidemiology 10 minute break 10:15 am Swimming Pool Inspection Priorities 11:15 am Swimming Pool Rules and Regulations 11:55 am Course conclusion and summary 12:00 pm Course end 3 1

2 BASICS OF POOL DESIGN AND HYDRAULICS Healthy Water Live Webcast- Public Swimming Pools, Spas, and Water Parks 4 Basics of Pool Design and Hydraulics Robert F. Foster, P.E. Mark Pabst Department of Health Bureau of Water Programs 400 West Robinson St., Suite S-532 Orlando, FL (407) Basics of Pool Design and Hydraulics All Public Swimming Pools are designed in accordance with Chapter 64E-9, Florida Administrative Code Copies of the Code may be downloaded at This presentation will cover Types of Pools, Appurtenances of Pools, System Hydraulics and Process Chemistry 6 2

3 Basics of Pool Design and Hydraulics Types of Pools The following slides depict several of the Types of Swimming Pools and Water Features that are permitted by the Florida Department of Health 7 Typical Skimmer Pool Typical Open Gutter Pool 3

4 Open Gutter Pool Simple Skimmer Pool Pool with Deck Level Perimeter Overflow 4

5 Zero Entry Pool with Interactive Features Zero Entry Pool with Interactive Features Swimming Pool with Slides 5

6 Typical Spa Pool Interactive Water Feature (Note Height of Sprays) Water Activity Pool with Slide 6

7 River Ride Pool (Portion) Basics of Pool Design and Hydraulics Pool System Hydraulics All Pools Must have an Overflow of Surface Water and a Main drain at the deepest point for underflow Surface Water contains most of the biological contamination in a pool and must be treated and disinfected Main drain flow is needed to assure good recirculation and to carry away heavy contaminants 20 Basics of Pool Design and Hydraulics Basic Pool Discharge Flows Overflow Pool Main Drain 21 7

8 Basics of Pool Design and Hydraulics Piping Design Pressure Piping is designed for a maximum flow velocity of 10 feet per second (fps) in the pipe Suction Piping is designed for a maximum flow velocity of 6 fps Gravity Flow piping is designed for a maximum flow velocity of 3 fps 22 Basics of Pool Design and Hydraulics Maximum Flow (gpm) Various Pipe Sizes Pipe Size 3 fps 6 fps 10 fps Basics of Pool Design and Hydraulics Main Drains All Main Drain Gratings in Florida must be designed to have a maximum flow velocity through their open area of 1.5 feet per second This applies to existing drains and new ASME A compliant drains that are installed in compliance with federal law You can figure the maximum flow through a main drain by multiplying open area (in square inches) by 4.7 The result is in gpm 24 8

9 Pool Main Drain (Note: Not VGB Compliant) Basics of Pool Design and Hydraulics Pool Pumps Most Pool Systems (and F.A.C. Code) require that pumps be sized for 60 ft. TDH (exception: Vacuum DE pumps sized for 50 ft. TDH) Using the flow velocities given before and reasonable pipe runs, this usually works There may be cases where the design engineer sized a pump for higher head capacity 26 Basics of Pool Design and Hydraulics Pool Pumps A conservative rule of thumb, if you don t have a pump curve, is that a pump will pump approximately 50 gpm per horsepower This may be adjusted by the Service Factor of the motor 27 9

10 Various Types of Pool Pumps Basics of Pool Design and Hydraulics Pool Filters There are two basic types of Pool Filters: Vacuum and Pressure You can always tell a vacuum filter because you can see the filter elements in the collector tank. Each type of filter has at least three possible filter media types: Diatomaceous earth (DE), cartridge, and sand Following are some pictures of various filter types 29 Sand Filters 10

11 Pressure DE Filters Vacuum DE Filters Pressure Cartridge Filters 11

12 Basics of Pool Design and Hydraulics Design Review Pool Construction Plan review checklist includes: Pool finish (impervious, slip-resistant, non-toxic, light in color) Pool size- 1 gpm transient, 0.75 gpm non-transient, 180 minute minimum turnover Shape and configuration (15 foot rule) Depth and No Diving markings Placement of steps and ladders (every 75 feet, one at each end, one at deep point if not at the end wall) 34 Basics of Pool Design and Hydraulics Design Review (Cont.) Ladder Design (cross-braced, proper height) Step design (treads at least 10 inches, risers no more than 10 inches, dark tile step edges per code, handrail in deck and bottom step and inches above deck and steps) Floor slopes (Between 1:10 and 1:40) and continuous Four foot wide deck sloped 2-4% away from pool, impervious and slip-resistant 35 Basics of Pool Design and Hydraulics Design Review (Cont.) Placement of gutters/skimmers, main drains, return inlets Piping is designed so that Flow is 100% through Gutters and 100% through Main Drain (or 60% through skimmers if applicable) Floor and wall return inlets and piping designed and located per code Placement of vacuum fittings Shower on deck within 20 feet 36 12

13 Basics of Pool Design and Hydraulics Design Review (Cont.) Sanitary facilities within 200 feet (when required) and in compliance for fixture count, floor finish, floor drains, diaper changing tables, hose bibb, etc. Pool Rules Sign per code requirements Pumps provided to supply proper flow Filters appropriately sized for requirements (2 gpm/ft² DE Filter; 15 gpm/ft² sand- 20 gpm/ft² if so rated by NSF; gpm/ft² cartridge Filter) 37 Basics of Pool Design and Hydraulics Design Review (Cont.) Chlorinators provided and NSF approved and sized to inject 6 ppm into return flow (divide flow rate by to get lbs/day required) ph control feeder provided Underwater and overhead lighting as required for night use (0.5 watts/ft² underwater/ 3 foot-candles overhead lighting) 38 Pool Ladder Detail 13

14 Step Detail Project Layout Typical Return Piping 14

15 Typical Pool Piping Diagram Typical Spa Piping Diagram Typical Spa Section View 15

16 Basics of Pool Design and Hydraulics Pool Equipment Must be NSF Approved All pumps, filters and chemical treatment equipment must be certified to be compliant with NSF Standard 50 (either by NSF or another qualified lab You can check whether a product has NSF approval by going to their web site: Click on Product Listings, Pool and Spa Equipment, then the type of equipment 46 Peristaltic Chemical Metering Pump Typical Erosion Chlorinator Hook-up 16

17 Typical Filter Package Units Vacuum DE Filter Grids (Square) Vacuum DE Filter Grids (Round) 17

18 DE Separation Tanks Vacuum Pump on Vacuum DE Filter Filter Tank Showing Auto Level Control and Main Drain/Overflow Control Valves 18

19 Sand Filter & Filter Pump Pressure Sand Filter (Vertical) Cartridge Filters (Compact Style) 19

20 Chemical Feed Pumps and ORP Controller Flowmeter Installation Air Gap to Waste 20

21 Basics of Pool Design and Hydraulics Gravity Flow vs. Direct Suction Florida has required gravity flow of main drains to a collector tank on all swimming pools and wading pools since 1977 Spa pools were allowed to have direct suction with an air vent line between 1984 and 1993 Vacuum filters are Always gravity flow Following are some filter configurations that you are likely to encounter 61 Typical Pre 1977 Direct Suction Pool Surge Tank Pump To Pool Pool Filter Main Drain Typical 1950 s Pool with Overflow Going to Waste To Waste Pump To Pool Pool Filter Main Drain 21

22 Typical Pre 1993 Spa with Air Vent To Atmosphere Pump To Pool SPA Skimmer Filter Air Vent Main Drain Typical Pressure Filter with Collector Tank Pool Collector Tank Pump Filter Typical Pool with Vacuum Filter To Pool Pool Filter Tank Pump 22

23 Collector tank (with No Valves) Probably Connected to Spa Pool Collector Tank Showing Auto Level Device and Main Drain and Gutter Valves Basics of Pool Design and Hydraulics Spa Design Criteria Timer for Therapy Pump ORP/pH Controller Extra Signage Alarm and sign if Safety Shut-off Switch Installed 69 23

24 Timer Switch & Emergency Cutoff for Spa Pool ORP/pH Controller BASICS OF WATER TREATMENT Healthy Water Live Webcast - Public Swimming Pools, Spas, and Water Parks 72 24

25 Basics of Water Treatment Chemical Parameters for Pools Required / Recommended (Regulated under 64E-9 F.A.C.) Chlorine Bromine ph Range ORP Range Cyanuric Acid Alkalinity Hardness 73 Basics of Water Treatment Chlorine Residuals Swimming Pools Free Chlorine mg/l at outdoor Pools Free Chlorine mg/l at indoor Pools All other types of Pools (Spas, IWF) Free Chlorine mg/l 74 Basics of Water Treatment Bromine Residuals Swimming Pools Free Bromine mg/l at outdoor Pools Free Bromine mg/l at indoor Pools All other types of Pools (Spas, IWF) Free Bromine mg/l 75 25

26 Basics of Water Treatment ph Range Effectiveness of chlorine is ph-dependent (at 68 F/20 C): ph % HOCl % OCl % 2.5% % 7.5% % 20.7% % 45.2% % 72.3% % 89.2% Handbook of Chlorination and Alternative Disinfectants, 3rd Edition, Geo. Clifford White, Basics of Water Treatment Oxidation-Reduction Potential (ORP) millivolts Required to be installed and maintained at all new Spas, Wading Pools, & Interactive Water Features* (*IWF - defined as no standing water over / in feature when not in operation) 77 Basics of Water Treatment Cyanuric acid (Stabilizer) Maximum for swimming pools 100 mg/l 40 mg/l recommended maximum Maximum level for spa pools 40 mg/l for existing spa Feeding chlorinated isocyanurates disinfectants is prohibited in new spas, wading pools & IWF. Existing isocyanurate feeders on these types must be replaced with non isocyanurate chlorinators, with ph adjustment feeders by June 01,

27 Basics of Water Treatment Alkalinity Recommended range mg/l Calcium Hardness Recommended range mg/l 79 27

28 28

29 29

30 Basics of Water Treatment Any Questions? 90 30

31 BASICS OF WATER SAMPLING AND TESTING Healthy Water Live Webcast- Public Swimming Pools, Spas, and Water Parks 91 Basics of Water Sampling and Testing Sampling Methodology: Collecting Water Samples Representative Samples: 18 inches below surface Away from return & dead spots Plastic sample container - not glass Test away from pool area 92 Basics of Water Sampling and Testing Sampling Methodology (cont.) Proper sample volume Hold at eye level Proper light Northern horizon 93 31

32 Basics of Water Sampling and Testing More Testing Techniques Never interchange reagents Use the correct amount of reagent NEVER USE FINGERS! Test immediately after sampling not necessary to wait to let hot samples cool Wait one turnover after treatment before testing again 94 Typical Chlorine & ph testing Equipment DPD Titration Testing More accurate High and low levels Accuracy to 0.2 ppm Easily observed end point opink to clear 32

33 Basics of Water Sampling and Testing Question: My test results indicate there is no chlorine in the pool, but I know there is. Why does this happen? Answer: If the chlorine is high, usually over 10 ppm, the DPD reagent may partially or totally bleach out, resulting in a false-low or zero chlorine reading. Add one drop of DPD #2 to your sample. If the pink color appears briefly, the water has a high chlorine level. As a second check, rinse out the test cell, add five drops each of DPD #1 and DPD #2 THEN add a few drops of the water to be tested. If you see pink, the chlorine level is high. 97 False DPD Bleaching of reagents ppm at normal ph oless intense o Colorless Basics of Water Sampling and Testing Q: My sample turns cloudy when I add DPD #1. Will the test still work? A: Yes. A sample usually turns cloudy when DPD #1 is added to water with high levels of hardness that precipitated out as calcium and/or magnesium salts. The cloudiness will not affect your test results and should disappear when you add DPD #2. To avoid cloudiness entirely, add the sample water to a test cell already containing 5 drops each of DPD #1 and DPD #

34 Basics of Water Sampling and Testing Q: Why aren t my free and total chlorine reading different when I know I have chloramines in the water? A: A small amount of DPD #3 was probably left in our test cell from a previous test. 100 Basics of Water Sampling and Testing Q: Can I use a chlorine comparator to test a bromine-sanitized pool? A: Yes. DPD undergoes the same chemical reaction with bromine as with chlorine, but the color intensities iti produced are different. If a chlorine comparator is used to test a brominesanitized pool, multiply the result by 2.25 to determine mg/l bromine. 101 Basics of Water Sampling and Testing ph Usual test method is measurement by a chemical indicator. phenol red indicator is in the range appropriate for pools & spas. Phenol red is yellow at 6.8, orange at 7.6, and red at 8.4. The color developed is caused by the proportions of yellow and red in solution

35 Basics of Water Sampling and Testing Q: Why do I sometimes get a blue/purple color instead of a yellow-to-red color when using phenol red indicator? A: High chlorine level in the pool (usually over 10 ppm) is interfering with the test. To eliminate, add 1 drop of chlorine neutralizer (thiosulfate, part of the alkalinity test) before adding the indicator solution. 103 Basics of Water Sampling and Testing Total Alkalinity Testing Titration Neutralize halogen o Sodium thiosulfate Measure the buffering o Using an acid titrant o Count the drops to end point o Calibration factor

36 Total Alkalinity Testing Starting End point Basics of Water Sampling and Testing Q: When I add my total alkalinity reagent I get a yellow endpoint instead of a red endpoint. Has the reagent gone bad? A: No. Your reagent is producing a yellow endpoint due to an excess of chlorine in the sample. Add an extra drop of thiosulfate reagent to the sample to remove the chlorine interference. 107 Total Alkalinity Testing High halogen False end points 36

37 Calcium Hardness Testing Step 1 Step 2 Raise ph Color indicator Basics of Water Sampling and Testing Q: I got a purple endpoint instead of a blue endpoint when I did a hardness test. What happened? A: There are metal ions interfering with the test, most likely copper ions from algaecides, pipes, or even the water itself. To avoid this problem, add five or six drops of titrant to the sample before adding the buffer and indicator, then proceed normal with the test. Always include the number of drops of titrant added at the beginning of the test when counting the total number of drops required to reach endpoint

38 Basics of Water Sampling and Testing Q: Since a drop-count test is all about seeing a color change, how can I be certain I ve reached the true endpoint of a reaction? A: A treated sample will show a mixture of the original color and the endpoint color as the titrant is added until the endpoint is reached. (For instance you will see both pink- and blue-colored water in your sample midway through a hardness test.) Add one more drop of titrant after the endpoint to be certain the color change was permanent. 112 Reaching True End Point Titrate Cyanuric Acid Test (Turbid metric) Amount of solid particles Scattering of light o Reagent reacts o Causing turbidity o Obscures black dot in tube 38

39 Basics of Water Sampling and Testing Q: What is the shelf life of my reagents? A: There is no simple answer because storage conditions play a major role in determining the freshness of any reagent. We prepare our liquid reagents to remain fresh for at least one year from the date of manufacture. It is best to replace your reagents seasonally. 115 Basics of Water Sampling and Testing Care of Test Kit Tighten Caps Store properly o Out of light o 36 F and 85 F Store away from all chemicals Discard frozen reagents 116 Basics of Water Sampling and Testing Any yquesto Questions? s