www.epa.gov/research technical BRIEF INNOVATIVE RESEARCH FOR A SUSTAINABLE FUTURE Testing and Evaluation of the Solstreme™ X35 ™ Portable UV Water Treatment Unit Introduction The U.S. Environmental Protection Agency's (EPA's) Homeland Security Research Program (HSRP) identifies and tests portable water treatment technologies that can be utilized for water disinfection and decontamination operations in support of emergency response. Optimally, the equipment should be easy to use by emergency responders, should be easy to transport in a standard pick-up truck (48 by 60 inches) (English units are used throughout this report except for light intensity and dosage units) and should not require a forklift for loading or off-loading. EPA does not provide any endorsement of these technologies. The Solstreme™ X35 ™ultraviolet (UV) germicidal water treatment unit first appeared on the market as a commercial product in 2013. The Solstreme X35 unit uses a patented microwave-actuated electrodeless lamp technology to provide UV disinfection. The electrodeless lamps can be run at higher power levels than electrode-based lamps, allowing them to produce greater amounts of UV light. Electrode-based lamps conform to the National Sanitation Foundation (NSF) Standard 55 "Class A" Rated UV systems specifications, which require operation at a minimum UV light dosage of 40 mJ/cm2 (millijoules/cm2), which is equivalent to 40 mW-sec/cm2 (intensity [milliwatts/cm2] x sec) (USEPA, 2003). The manufacturer expects the electrodeless Solstreme X35 unit operating under optimal conditions to deliver an equivalent total dosage of up to 1,700 mW-sec/cm2 (NeCamp, 2008). However, the design of the X35 unit makes it difficult to verify the dosage. The Solstreme X35 manufacturer has developed conversion tables to correlate the flow rate and power settings (1 through 5) to UV dosage. See Appendix 1. The Solstreme X35 unit was originally designed for use in developing countries that are without access to dependably safe water supplies. The unit was made to be portable (approx. 75 lbs) for delivery to remote communities and to treat any form of raw water that has been treated with adequate pre filtration (50 to 100 microns). The unit uses a patented process and materials to focus the UV waves such that doses as high as 120 mJ/cm2 can be achieved with this compact size unit. The unit is locally supported by the Solstreme company in Cincinnati, Ohio. The X35 unit as tested by EPA costs approximately $15,000 with another $1000 needed for sampling equipment and install and set up. The lamp life is three years. Initial Solstreme X35 unit testing against Bacillus globigii at EPA's T&E Facility, June 2015 The Solstreme X35 unit was initially tested against Bacillus globigii, a surrogate for Bacillus anthracis, in June 2015 at EPA's Test and Evaluation (T&E) Facility in Cincinnati, Ohio. The testing was done on the 3-inch line drinking water distribution system simulator (DSS), which consists of approximately 1200 June, 2017 EPA/600/S-17/383 Page 1 ------- feet of piping. Tap water from the Greater Cincinnati Water Works (GCWW) is pumped through the DSS where contaminants can be injected. See USEPA, 2009, for a complete description of the DSS. This experiment was conducted using a flow rate of 8 gallons per minute (gpm) through the DSS. Chlorinated tap water enters the T&E Facility directly from the GCWW distribution system and flows into a 1,000- gallon tank located on the floor of the facility. The water is then pumped to an elevated 750-gallon storage tank and gravity-fed to the DSS. The water from the 750 gallon tank was injected with over 10 million colony forming units (CFU) of B. globigii as it exited the DSS and was plumbed directly into the Solstreme X35 unit as shown in Figure 1. The lamp intensity during the time frame that the slug passed through the unit ranged from 55-64 Solstreme units (SU). Solstreme Units (SU) were derived by the manufacturer. Conversion tables are provided by the manufacturer in Appendix 1 for 5 average UV dosages. With an optimal flow rate of 8 gpm and an observed Solstreme reading of 55 to 64, the dosage of 158 rmJ/ sq cm corresponds to a destruction percent of 99.999 or a 5- log reduction based upon MS2 coliphage inactivation. Table 1 summarizes the results from the B. globigii analysis of water samples collected during this study. The average concentration of B. globigii from the inlet samples collected was approximately 23 million CFU/100 mL Individual inlet concentrations were compared to the outlet concentrations in order to compute the log reduction values shown in Table 1. The results indicate that the X35 unit was very effective (up to 6.9-log reduction) at inactivating B. globigii which was better than the Appendix 1 tables based upon MS2 coliphage inactivation predicted. Table 1: Bacillus globigii Disinfection and UV Exposure Time (Based on Exposure to the Solstreme™ X35 Unit) SAMPLE ID (Exposure time) Average Solstreme™ X35 Inlet B. globigii concentration CFU per 100 mL Solstreme™ X35 Outlet B. globigii concentration CFU per 100 mL Log reduction Pretest/baseline 0.00E+00 0.00E+00 - 10 minutes 2.33E+07 1.37E+02 5.2 15 minutes 2.33E+07 6.00E+01 5.6 20 minutes 2.33E+07 1.05E+02 5.3 25 minutes 2.33E+07 2.60E+01 6.0 30 minutes 2.33E+07 3.00E+00 6.9 Figure X, Solstreme™ X35 ™ unit set up at EPA's T&E Facility (vertical cell). June, 2017 Page 2 ------- Experiment Design at Idaho National Lab Based upon the promising results of the Solstreme X35 unit testing at the T&E facility in Cincinnati, EPA decided to test the X35 unit on a full-scale replica of a drinking water distribution system, the water security test bed, at the Idaho National Laboratory. This Idaho water security test bed (WSTB) experiment was designed to assess the ability of a portable disinfection unit to treat a large volume of water contaminated with B. globigii spores. When disinfectant is added to contaminated water, it reacts with the microbes, but also with other impurities in the water. So the demand on the disinfection agent by other impurities must be met, and there must be a sufficient residual disinfectant concentration to effectively treat the microbial contaminants. The water in the lagoon contained dirt and sediment from the surrounding area, as well as algae. The dirt and algal growth created a disinfectant demand in the water and rendered the water "dirty." The X35 unit was tested along with 4 other technologies for the ability to treat this dirty water contaminated with spores. The effectiveness of the Solstreme™ X35 unit was evaluated by sampling water contaminated with B, globigii spores before it entered the unit, before treatment began, and then after disinfection to determine the treatment effectiveness. The concentration of spores in the influent (or before treatment began) was then compared to the concentration in the effluent (after treatment). The matrix water for the X35 unit experiment was pumped from the lagoon into a 2,000-gallon flexible bladder tank. The spores were added to the filled bladder tank, which contained a mixing pump to ensure a continuous stream of B. globigii spores were provided to the treatment unit (Figure 2). Bacillus globigii Mixing Pump Feed Lines to Mix Ports Solstreme™ X35 Feed Pump Figure 2. Inlet bladder tank and mixing. Figure 3 shows a schematic depiction of how the mixing pump was connected to the bladder to perform mixing along with the inlet and outlet ports. June, 2017 Page 3 ------- Mixing Port Inlet Port from Lagoon Mixing Port Mixing Bladder (10.5' x 14.5') Mixing Port Outlet Port to Mixing Pump Feed Port Mixing Pump AOP and Solstreme Pump Figure 3. Schematic depiction of the inlet bladder tank mixing process. (Source: U.S. EPA. 2016. Testing large volume water treatment and crude oil decontamination using the Water Security Test Bed at the Idaho National Laboratory. EPA/600/R-161/126) For the Solstreme X35 unit, a target inlet concentration of greater than 106 spores/100 mL (or 104 spores/mL) was prepared using the inlet bladder tank and mixing pump shown in Figure 3. The water was then pumped to the treatment unit. The X35 unit was tested for 5.5 hours. Pre-treatment and post- treatment water samples for B. globigii analysis were collected at the same time. Idaho Field Testing of the Solstreme™ X35 Unit In 2015, the large volume disinfection study using Solstreme X35 unit, was performed at the WSTB at the Idaho National Laboratory in Scoville, Idaho. The X35 unit setup is depicted in Figure 4. June, 2017 Page 4 ------- Electrodeless Lamp/Flow cell Water Inlet \ x Water Outlet Figure 4. Solstreme™ X35 UV unit and effluent bladder tank (blue object in front of the UV system), The baseline water sample (BWS) for B. globigii concentrations (BWS-0 through BWS-6, time points over a 5.5-hour duration) were collected from the inlet and outlet of the system simultaneously using the grab sampling technique in 100-mL sterile sample bottles with a 10 mg sodium thiosulfate tablet. The sodium thiosulfate was used to eliminate any remaining chlorine in the samples so the true cell density of the bacteria could be enumerated. The BWS sampling ports at both inlet and outlet of the system were opened, and the water was drained for 15 seconds prior to collection of the sample. Idaho Field Test Results for Solstreme™ X35 Unit Testing The Solstreme X35 unit disinfects water through UV light only. Figure 5 shows the X35 unit's influent spore density (blue bars) and the density of spores in the treated effluent (orange bars). Influent and effluent samples were taken simultaneously, so the difference between the bars at each time point represents the amount of spore inactivation taking place, or log reduction (green line) at that point in time. The influent spore density, over the course of the experiment, was approximately 1.6* 105 CFU/ml. This was a positive finding since a consistent influent concentration was desired over the course of the experiment. The effluent spore densities from the Solstreme X35 unit consistently decreased as the experiment progressed. A corresponding increase in spore log reduction over the course of the experiment was also observed. After discussing this finding with the X35 unit's manufacturer, a possible reason for this increase in disinfection performance emerged. The X35 unit's UV output is higher at higher temperatures. Over the course of the experimental period (from early morning to mid-afternoon), the air and lagoon water temperature at the test site increased from 12° to 28 C and from 15° to 25 C, respectively. It should be noted that no free-chlorine residual was detected in the water. Figure 6 shows the log reduction data from Figure 5 plotted against the output intensity from the Solstreme X35 unit over the course of the experiment. The X35 unit's output intensity is a unitless measure of the UV output derived by the manufactured called Solstreme Units (SU). Typically, for an electrode-based UV bulb, the intensity is measured in mill watts per square centimeter (mW/cm2). June, 2017 Page 5 ------- However, the electrodeless design of the X35 unit does not allow for direct conventional radiometer- based UV intensity measurements. Figure 6 provides an indirect measure of the UV intensity based on achievement of 3.5- to 4-log inactivation of B. globigii spores in lagoon water with —11 to 13 NTU turbidity (pH of approximately 7.5). This turbidity was higher than the initial X35 unit's testing against Bacillus globigii at T&E facility in 2015, which was well below 1 NTU. See EPA Wastewater technology fact sheet EPA 832-F-99-064 The increase in output intensity of the Solstreme X35 unit in Figure 6 is perhaps due to the increase in water temperature over the course of the experiment. In the future, it may be beneficial to add a heating element to the X35 unit's influent water line to bring water to a temperature between 25° to 30°C and a pre-filter to reduce the disinfection demand in the water. Increased disinfection may be due to hydroxyl radical formation due to photolysis of the water with higher temperature. The influence of air and water temperature on disinfection performance merits further investigation. l.E+06 £ l.E+05 D Li. JJ ii l.E+04 2.0 _l 1.0 0.0 ( -• 3 S 10 IS 20 25 30 Solstreme Intensity (unitless) June, 2017 Page 6 ------- Figure 6. Spore log reduction for Solstreme™ X35 UV unit treatment vs. UV output intensity. Solstreme™ X35 unit output intensity is a proprietary, unitless measure of UV intensity. Table 2 contains a summary of the Solstreme X35 unit's performance results from Idaho. The X35 unit performed well in the field where log reductions of 3.5 to 4.0 were observed. The X35 unit achieved an average spore log reduction of 3.7, with log removal increasing from 3.0 to 4.0 over the course of the 5.5 hr. experiment. This increase could have been due to the increase in temperature experienced during the daylight hours elevating the UV output/efficiency and leading to greater disinfection. Two thousand gallons of water were treated during the experimental run. However, due to the differences discussed above, it did not achieve the over 6-log reduction observed at the T&E facility lab setting. For the full report on the performance of the Solstreme™ X35 unit and three other water treatment technologies at the Idaho National Lab, please see USEPA, 2016. Table 2. Mobile Water Treatment Unit Performance Summary Water Treatment Technology Tested Capital Cost Average Log Reduction Volume Treated (gal) Flow (gpm) Performance Summary Solstreme™ X35 (UV) $15,000 3.5 to 4.0 2,000 5 Stable, immediate disinfection, easy to transport and set up. X35 testing against Escherichia coli at T&E Since EPA had previously determined the performance of the Solstreme X35 unit in the lab and in the field against Bacillus globigii, the researchers decided to challenge the X35 with another bacterial contaminant, Escherichia coli, at the T&E facility in 2017. This experiment was also conducted using a flow rate of 8 gallons per minute (gpm) through the DSS. As with the previous B. globigii study at T&E, chlorinated tap water entered the T&E Facility directly from the GCWW distribution system and flowed into a 1,000-gallon tank located on the floor of the facility. The water was then pumped to an elevated 750-gallon storage tank, and gravity-fed to the DSS. Prior to and during the entire test, the contents of the 750-gallon storage tank were dechlorinated using sodium thiosulfate. The sodium thiosulfate solution was continually pumped into the storage tank using a chemical feed pump. This was done to prevent the E. coli from being killed by the residual chlorine from Cincinnati tap water, which would have confounded the results for the X35 unit's inactivation testing. Complete dechlorination through the DSS was confirmed by continuous online readings from a Hach® CI-17 free-chlorine analyzer (Hach, Loveland, CO) and grab samples analyzed by the Hach DPD (N,N diethyl-1,4 phenylenediamine sulfate) method. The E. coli was injected into the dechlorinated water exiting the 750-gallon tank and was plumbed directly into the X35 unit as previously shown in Figure 1. The flow of E. co//'-contaminated water through the Solstreme X35 unit was maintained at 8 gpm using an inline control valve and rotameter combination. The observed lamp intensity during the injection period ranged from 65-74 Solstreme units. The manufacturer supplied conversion tables in Appendix 1 provide a dosage value of 210 mJ/cm sq. based on an optimal flow rate of 8 gpm at observed intensities of 65 to 74 SU. The average UV dosage of 210 mJ/cm sq. corresponds to a destruction percent of 99.9999 or a 6-log reduction based upon MS2 coliphage inactivation. (See Appendix 1) June, 2017 Page 7 ------- Table 3 summarizes the results from the E. coli analysis of water samples collected during this study. The average concentration of E. coli which was injected into the pipe flowing into the Solstreme unit was 5.70E+06 CFU/100 ml_. Individual inlet concentrations were compared to the outlet concentrations in order to compute the log reduction values shown in Table 3. The results indicate that the X35 unit was very effective (consistent 6-log reduction) at inactivating E. coli which was the response predicted from the MS2 coliphage tables in appendix 1. Table 3: Summary of Escherichia coli Disinfection Results (based on exposure to the Solstreme™ X35 unit) SAMPLE ID Solstreme™ X35 unit's Inlet E. coli concentration CFU per 100 mL Solstreme™ X35 unit's Outlet E. coli concentration CFU per 100 mL Log reduction Pretest/baseline 0.00E+00 0.00E+00 - 15 minutes 6.13E+06 0.00E+00 6 30 minutes 6.87E+06 0.00E+00 6 45 minutes 6.87E+06 0.00E+Q0 6 60 minutes 2.91E+06 0.00E+00 6 Testing of the UVLS 1000 unit against Escherichia coli at T&E In 2017, the inventor and patent holder of the Solstreme X35 unit contacted EPA about a prototype next-generation Solstreme X35 unit to be sold as the UVLS-1000 unit. This unit is capable of treating Figure 7. Solstreme™ X35 UVLS-1000 Device (Horizontal Cell). Figure 8. Solstreme™ X35 UVLS-1000 Unit. drinking water at a flow rates of up to 20 gallons per minute with the approximate same weight and shape as the X35 unit per the manufacturer. This prototype unit also has the ability to operate at seven different UV power levels. The Solstreme™ X35 UVLS-1000 unit used in this evaluation at the T&E Facility had two different configurations - one with the UV cell in the horizontal position and the other with the UV cell in the vertical position (Figures 7 and 8). The effect of air pockets and bubbles in the flow cell can reduce decontamination efficiency so the flow cell can be oriented horizontally or vertically. June, 2017 Page 8 ------- Five test runs were made with the UVLS-1000 unit at two flow cell configurations (horizontal and vertical) and two power settings (1 and 7) with various flow rates from 5 to 11 gpm as shown in Table 4. Throughout the tests, as the B. globigii slug was passing through the device, the UV intensity of the prototype unit was recorded. Table 4 presents the observed UV intensity range (in SU units) for each test during the time period that the slug was passing through the device. Results of T&E testing of UVLS 1000 Table 4 summarizes the results from the B. globigii analysis of water samples collected during these tests. Individual inlet concentrations were compared to the corresponding outlet concentrations in order to compute the log reduction values. Samples were taken prior to injection and, 5, 10 and 15 min after injection. The baseline or prior sample does not return to zero for tests 2, 3 ,4, and 5 because the line was just flushed between tests and the residual B. globigii requires higher concentrations of chlorine to return to zero. Table 4: Summary of Bacillus globigii Disinfection Results for Solstreme™ X35 UVLS-1000 Unit Configuration SAMPLE ID Flow Rate, gpm Power Level UV Intensity Range (mJ/sq cm) Unit's inlet B. globigii concentration CFU/100 mL Unit's outlet B. globigii concentration CFU/100 mL Log reduction Horizontal Test 1 11 1 128-139 Cell 1-1 (background) 0.0E+00 0.0E+00 - 1-2 (5 min) 6.3E+07 1.0E+04 3.8 1-3 (10 min) 6.4E+07 8.2E+03 3.9 1-4 (15 min) 6.4E+06 3.4E+02 4.3 Test 2 8 1 122-132 2-1 (background) 1.7E+04 5.0E+01 2.5 2-2 1.4E+08 5.6E+03 4.4 2-3 2.0E+08 6.8E+03 4.5 2-4 2.6E+08 3.1E+03 4.9 Test 3 5 1 130-140 3-1 (background) 1.9E+04 0.0E+00 4.3 3-2 6.3E+07 1.0E+03 4.8 3-3 7.3E+08 3.1E+03 5.4 3-4 4.9E+08 3.0E+03 5.2 Vertical Test 4 5 7 185-203 Cell 4-1 (background) 2.7E+03 0.0E+00 3.4 4-2 1.7E+07 1.3E+03 4.1 4-3 2.6E+07 1.8E+03 4.2 June, 2017 Page 9 ------- Configuration SAMPLE ID Flow Rate, gpm Power Level UV Intensity Range (mJ/sq cm) Unit's inlet B. globigii concentration CFU/100 mL Unit's outlet B. globigii concentration CFU/100 mL Log reduction 4-4 6.4E+07 3.4E+03 4.3 Test 5 10 7 195-205 5-1 (background) 1.1E+04 5.0E+00 3.3 5-2 1.2E+07 7.0E+03 3.2 5-3 1.5E+07 5.7E+03 3.4 5-4 1.9E+07 6.4E+03 3.5 As shown in Table 4 , B. globigii spores were present in most of the outlet samples as the B. globigii slug passed through the prototype Solstreme™ X35 UVLS-1000 unit. Comparing inlet and outlet concentrations, the UVLS-1000 unit, in the horizontal position at power level 1, demonstrated a maximum log reduction of 4.3 operating at 11 gpm, 4.9 operating at 8 gpm flow, and 5.4 operating at 5 gpm. In the vertical position at power level 7, the UVLS-1000 unit demonstrated a maximum log reduction of 4.3 operating at 5 gpm and 3.5 operating at a 10 gpm flow. Conclusions The Solstreme™ X35 unit overall was able to consistently disinfect E. coli contamination to over 6 log reductions. The technology was able to consistently inactivate Bacillus globigii spores from 3.5 to 5.0 log reductions at flow rates from 5 to 11 gpm. These positive results warrant further use and testing by emergency response personnel in the field. The X35 unit is light weight and can be transported easily to the site of an emergency response. The unit is easy to use and can be quickly connected to contaminated water and begin disinfection in a self-contained treatment unit. This technology can be operated via standard 120-volt electrical service or a portable generator. The prototype UVLS 1000 unit did not demonstrate improved spore inactivation performance from the Solstreme™ X35 unit previously tested against Bacillus spores at the T&E facility and was only slightly better than the X35 unit tested at the water security test bed in Idaho. The influence of turbidity, air pockets, and water temperature affects disinfection performance and merits further investigation for this particular unit. References NeCamp, D.R. 2008. X-35 Ultraviolet Water Purification system. 'A discussion of X-35 ultraviolet technology and its benefits.' X-3-5 LLC, Cincinnati, Ohio, USA: Solstreme™ X35. Rice, E.W., Adcock, N.J., Sivaganeson, M. and Rose, L.J. 2005. Inactivation of spores of Bacillus anthracis Sterne, Bacillus cereus, and Bacillus thuringiensis subsp. israelensis by chlorination. Applied and Environmental Microbiology, 71 (9):5587-5589. U.S. Environmental Protection Agency (USEPA). 1999. Wastewater technology fact sheet: ultraviolet disinfection. EPA 832-F-99-064 June, 2017 Page 10 ------- U.S. Environmental Protection Agency (USEPA). 2016. Testing large-volume water treatment and crude oil contamination using the EPA water security test bed experiments at the Idaho National Laboratory. EPA/600/R-161/126 U.S. Environmental Protection Agency (USEPA). 2009. Distribution system water quality monitoring: Sensor technology evaluation methodology and results. EPA 600/R-09/076 U.S. Environmental Protection Agency (USEPA). 2003. Ultraviolet disinfection guidance manual. Washington, DC: U.S. EPA. EPA/815/D-03/007 Contact Information For more information, visit the NHSRC Web site at www.epa.gov/homeland-securitv-research Technical Contact: John Hall (hall.iohn@epa.gov) General Feedback/Questions: Kathy Nickel (Nickel.kathy@epa.gov) U.S. EPA's Homeland Security Research Program (HSRP) develops products based on scientific research and technology evaluations. Our products and expertise are widely used in preventing, preparing for, and recovering from public health and environmental emergencies that arise from terrorist attacks or natural disasters. Our research and products address biological, radiological, or chemical contaminants that could affect indoor areas, outdoor areas, or water infrastructure. HSRP provides these products, technical assistance, and expertise to support EPA's roles and responsibilities under the National Response Framework, statutory requirements, and Homeland Security Presidential Directives. June, 2017 Page 11 ------- Appendix 1. Table A1. Prototype Solstreme™ X35 ™ ULVS-1000 Unit's Calculated Dosages Based on MS2 Coliophage Inactivation U V Treatment Data Calculated * Date Time Sample Description Flow Rate (GPM) Observed Intensity (SU) Intensity (mW/cm2) Exposure (sec) Dosage (mJ/cm2) Log Reduction Horizontal Configuration Power Level 1 ll-Jul-17 10:40 Outlet 1-1 Background Sample - treated/ no BG 11.0 137 177 2.18 386 0 ll-Jul-17 11:44 Outlet 1-2 UV Treated - BG 11.0 128 165 2.18 360 3.8 ll-Jul-17 11:46 Outlet 1-3 UV Treated - BG 11.0 130 168 2.18 367 3.9 ll-Jul-17 11:51 Outlet 1-4 UV Treated - BG 11.0 133 172 2.18 375 4.3 ll-Jul-17 12:55 Outlet 2-1 Background Sample - treated/ no BG 8.0 131 169 3.00 507 2.5 ll-Jul-17 14:03 Outlet 2-2 UV Treated - BG 8.0 125 161 3.00 483 4.4 ll-Jul-17 14:08 Outlet 2-3 UV Treated - BG 8.0 125 161 3.00 483 4.5 ll-Jul-17 14:13 Outlet 2-4 UV Treated - BG 8.0 122 157 3.00 471 4.9 12-Jul-17 9:56 Outlet 3-1 Background Sample - treated/ no BG 5.0 139 179 4.80 859 4.3 12-Jul-17 11:34 Outlet 3-2 UV Treated - BG 5.0 131 169 4.80 811 4.8 12-Jul-17 11:37 Outlet 3-3 UV Treated - BG 5.0 130 168 4.80 806 5.4 12-Jul-17 11:40 Outlet 3-4 UV Treated - BG 5.0 131 169 4.80 811 5.2 Vertical Configuration Power Level 7 18-Jul-17 10:09 Outlet 4-1 Background Sample - treated/ no BG 5.0 203 262 4.80 1257 3.4 18-Jul-17 11:44 Outlet 4-2 UV Treated - BG 5.0 189 244 4.80 1170 4.1 18-Jul-17 11:49 Outlet 4-3 UV Treated - BG 5.0 186 240 4.80 1152 4.2 18-Jul-17 11:54 Outlet 4-4 UV Treated - BG 5.0 185 239 4.80 1146 4.3 18-Jul-17 13:25 Outlet 5-1 Background Sample - treated/ no BG 10.0 202 261 2.40 625 3.3 18-Jul-17 14:20 Outlet 5-2 UV Treated - BG 10.0 195 252 2.40 604 3.2 18-Jul-17 14:25 Outlet 5-3 UV Treated - BG 10.0 195 252 2.40 604 3.4 18-Jul-17 14:30 Outlet 5-4 UV Treated - BG 10.0 197 254 2.40 610 3.5 Intensity and dosage computations are based on Solstreme's testing with MS2 Coliophage. Bg, Bacillus globigiT, gpm, gallons per minute; UV, ultraviolet Units: mJ/cm2, millijoules/square centimeter; mW/cm2, milliwatts/sqare centimeter; sec, seconds of exposure in device; SU, Solstreme Units; June, 2017 Page 12 ------- Table A2. Manufacturer Supplied Log Reduction Conversion Table for Solstreme Units (SU) Versus Max Flow at 5 Dosage Settings Based on MS-2 Coliphage Inactivation. Optimal Flow Rate ¦ GPM EHffilZEEl Flow Intensity {X35 Seal*} Rate 6 1.0 9 1.5 12 2 0 15 2,5 18 3.0 21 3.5 24 4.0 26 4.5 29 50 32 5.5 35 6.0 38 65 41 70 44 7,5 47 8.0 50 85 52 9.0 55 9,5 58 10.0 61 10.5 64 110 67 115 70 120 73 12 5 76 13.0 78 135 81 14 0 84 14 5 87 150 MS2 Collophagc Ina ctivation Guidelines Destruction % X35 Unit Dosage 99.99 126 99 999 158 99 9999 210 99.99999 264 99.999999 310 UV Dosage 158 UV Dosage 210 UV Dosage 264 Safety Factor 0.1 Safety Factor 0.1 Safety Factor 0.1 Intensity (X35 Scalo) Flow Rate (GPM) Intensity (X35 Scale) Flow Rato (GPM) Intensity (X3S ScaIo) 13 Flow Rate (GPM) [ 1.0 8 1,0 10 10 11 1.5 15 1.5 19 1.5 15 2.0 20 2.0 25 2.0 19 25 25 2.5 31 2 5 22 3.0 29 3.0 37 3.0 26 3 5 34 3.5 43 3.5 29 40 39 4.0 49 4.0 33 4.5 44 4.5 55 4.5 37 5.0 49 5.0 61 5,0 40 5.5 53 5.5 67 5.5 44 6.0 58 6.0 73 6.0 48 6,5 63 6 5 79 6.5 51 7.0 68 7.0 85 7.0 55 75 73 7.5 91 7.5 58 8,0 77 8.0 97 8.0 62 8.5 82 8.5 103 8.5 66 9.0 87 9.0 109 9.0 69 9.5 92 9 5 115 9.5 73 10.0 97 10.0 121 10.0 77 10 5 102 105 128 10.5 80 11,0 106 110 134 11.0 84 115 111 11.5 140 11 5 87 120 116 12,0 146 12.0 91 125 121 12.5 152 12.5 95 130 126 130 158 130 98 13.5 130 13,5 164 13.5 102 140 135 14 0 170 14.0 106 14 5 140 145 176 14.5 109 150 145 15.0 182 15 0 im-irrrfEH ES3JEHS1MKH1 Flow Intensity (X3S Scale) Rate 15 1 0 22 1 5 29 20 36 2.5 43 30 50 35 57 4.0 64 4.5 72 50 79 5.5 86 6.0 93 6.5 100 7.0 107 7.5 114 8.0 121 8.5 128 9.0 135 9 5 143 10.0 150 10.5 157 11.0 164 11.5 171 120 178 12 5 185 13.0 192 13.5 199 140 207 14.5 214 150 June, 2017 Page 13 ------- |