Updated on January 3, 2024


Created on August 27, 2015



WaterGuard is a dilute sodium hypochlorite solution used as a point-of-use treatment for household drinking water.

Tested By
  • Center for Disease Control (CDC)
Content Partners


Product Description

WaterGuard (also know as Sur’Eau in French-speaking regions) is a household chemical water treatment method distributed by Population Services International (PSI). This point-use water treatment is a controlled chlorine dosing method. It does not require the level of monitoring or use of complex equipment like traditional gas systems. WaterGuard is part of the Safe Water System (SWS), a water quality intervention program to be used in collaboration with safe water storage, and behavioral change communication. Correct use of the product in combination with SWS has shown to reduce diarrheal disease incidence in users by 22-85%.

Target SDGs

SDG 6: Clean Water and Sanitation

SDG 3: Good Health and Well-Being

Market Suggested Retail Price


Target Users (Target Impact Group)


Distributors / Implementing Organizations

The PSI is the major community distributor. Partnerships with PATH (funded by the Bill and Melinda Gates Foundation & CDC), the University of Malawi in conjunction with CDC, Pan American Health Organization (PAHO) and World Health Organization (WHO), have also facilitated distribution and implementation of the product.

Competitive Landscape

Manufacturing/Building Method

The product is listed as locally manufactured, details on the manufacturing process are not discussed.

Intellectural Property Type


User Provision Model

Users are most likely to purchase WaterGuard from their local supermarket, pharmacy, or street vendors. In some rural areas, users can contact WaterGuard's community sales agents to obtain the product.

Distributions to Date Status

WaterGuard bottles have been distributed worldwide in WASH intervention strategies. The number of products distributed to date is unknown but is estimated to be over 1,000,000s with 30,000 units delivered to Monrovia, Liberia in 2012 alone.

Active Chemical and concentration (%)

Sodium Hypochlorite, 1.25%



Dosing method: Batch or flow-through


Dosing method: Automatic or manual


Dosing quantity

3mL (1 cap) per 20L for water >30NTU

6mL (2 caps) per 20 L for water >100NTU

Contact time (min)

30 mins

Target free disinfectant residual (mg/L)

2 mg/L

Bacteria reduction

2 log (E. coli)

Virus reduction

2 log (enteroviruses)

Protozoa reduction

3 log (E. Histolytica, G. Lambilia, Cryptosporidium.)

Heavy metals and/or arsenic reduction


Treatment lifespan (days)

7 days if treated water is stored in a narrow neck container with a tight fitting.

Maximum recommended influent turbidity level (NTU)

>100 NTU

Design Specifications

The water treatment product is made from sodium hypochlorite, 12.5% diluted to 1.25% by weight. The 150mL standard bottle is suggested to serve a family’s water needs for approximately a week. The cap is used for measuring doses, with one cap referred to as a single dose. A cap of WaterGuard 3mL is added to 20L of water >30NTU, in a container with a tight-fitting lid. The container is agitated and left for 30min for sanitation to complete. Two caps are required for water with high turbidity levels (>100NTU), with pre-filtration methods recommended before the addition of WaterGuard.

Product Schematics

Technical Support

PSI has an info-graphic showing the appropriate use of this product. Users may also refer to the Safe Water Training Manual for Village Health Teams, created by PSI Uganda and UNICEF.

Replacement Components

Not applicable


Sodium hypochlorite degrades over time. Studies have found that in ideal conditions, chlorine concentration significantly decreases. Products of original concentration 13% sealed, at 80F, away from direct sunlight, were found to decrease in concentration to 8% over 75 days. This should be taken into account when treating water. Users must consult Federal, State, and Local regulations for disposal.

Manufacturer Specified Performance Parameters

This water treatment is designed to remove 99.9% of bacteria.

Vetted Performance Status

Testing performed by the CDC determined a 22-84% reduction in diarrhea incidence. Field use in rural Tanzania has found a 95.4% TTC reduction after water was treated with WaterGuard.


The product should be used as per dosage guidelines. The maximum use limit must not exceed 84mg/L. This product should not be mixed directly with any other chemical. Microbiological effectiveness is limited by turbidity of the raw water. The effectiveness of WaterGuard decreases proportionately to turbidity levels. WaterGuard is unable to effectively treat raw water with turbidity levels greater than 100NTU. The use of chlorine water treatment is hazardous if incorrectly monitored. Trihalomethanes (THMs) are formed in drinking-water as a result of chlorination of organic matter present in raw water supplies. High concentrations of these compounds are linked to a variety of health issues such as cancer and reproductive issues. The World Health Organisation advises THM levels in drinking water to be kept as low as possible. The point-of-use chlorination of water in Kenya has shown compliance with WHO THM guideline values.

Complementary Technical Systems

If the water turbidity is greater than 30NTU, 2 caps must be used. Preliminary filtration using a cloth is recommended before adding WaterGuard. If NTU is greater than 100NTU alternative treatments should be used, as WaterGuard is ineffective at these levels.

Academic Research and References

Luoto, et al. 2011, What point-of-use water treatment products do consumers use? Evidence from a randomized controlled trial among the urban poor in Bangladesh, PLoS One; 6(10): e26132

Reller et al., 2001, Cholera Prevention With Traditional and Novel Water Treatment Methods: An Outbreak Investigation in Fort-Dauphin, Madagascar, Vol91, No.10

Tersagh, I, et al., 2015. Efficacy of Water Guard Disinfectant as a Domestic Stored Water Treatment Method in Makurdi Metropolis. Research Journal of Environmental Sciences, 9: 364-369.

Mohamed, H., et al, 2015, Point-of-use chlorination of turbid water: results from a field study in Tanzania, Journal of Water and Health, 13 (2): 544-552.

Yohanna, L., and Mashauri, D., 2008, Potential Use of WaterGuard as a disinfectant for domestic water use Tanzania Journal of Engineering and Technology 31(2): 62-69

Lule JR., et al. 2005, Effect of home-based water chlorination and safe storage on diarrhea among persons with human immunodeficiency virus in Uganda. American Journal of Tropical Medicine & Hygiene. 2005;73(5):926?933.

H. Mohamed, T. Clasen, R. M. Njee, H. M. Malebo, S. Mbuligwe, and J. Brown, “Microbiological effectiveness of household water treatment technologies under field use conditions in rural Tanzania,” Trop. Med. Int. Health, vol. 21, no. 1, pp. 33–40, 2016.

E. Hood, “Tap water and trihalomethanes: Flow of concerns continues,” Environ. Health Perspect., vol. 113, no. 7, pp. A474–A474, 2005

D. S. Lantagne, B. C. Blount, F. Cardinali, and R. Quick, “Disinfection by-product formation and mitigation strategies in point-of-use chlorination of turbid and non-turbid waters in western Kenya,” J. Water Health, vol. 6, no. 1, pp. 67–82, 2008.

P. Makutsa et al., “Challenges in implementing a point-of-use water quality intervention in rural Kenya,” Am. J. Public Health, vol. 91, no. 10, pp. 1571–1573, 2001.

“Where We Work?:,” PSI, 18-Sep-2021/ Available: https://www.psi.org/where-we-work/

“Water Disinfection with Chlorine and Chloramine,” Cdc.gov, 18-Nov-2020. Available: https://www.cdc.gov/healthywater/drinking/public/water_disinfection.html

“P&G purifier of water packets – a simple way to clean water,” Csdw.org. Available: https://csdw.org/pg-purifier-of-water-packets/

“Goal 6,” Sdgs.un.org. Available: https://sdgs.un.org/goals/goal6

“Water, Sanitation and Hygiene?:,” PSI, 03-Mar-2020. Available: https://www.psi.org/practice-area/wash/

Alnap.org. Available: https://www.alnap.org/system/files/content/resource/files/main/wash-systematic-review.pdf

Fhi360.org. Available: https://hip.fhi360.org/file/21859/PG%20Unit%203.pdf

“Preventing diarrheal disease in developing countries: Proven household water treatment options,” Cdc.gov, 2008. Available: https://www.cdc.gov/safewater/publications_pages/proven.pdf

waponline.com. Available: https://iwaponline.com/jwh/article/13/2/544/28357/Point-of-use-chlorination-of-turbid-water-results

“Global network,” CARE International. Available: https://www.care-international.org/who-we-are/global-network

Compliance with regulations

The product is endorsed by PSI and complies with the South African National Standard 241 Drinking Water Specifications.

Evaluation methods

The manufacturer product cites log 4 removals of bacteria for water treated with WaterGuard. The evaluation criteria primarily are for the removal of E.coli, E. Histolytica, G. Lambilia, Cryptosporidium enteroviruses. Third-party testing is conducted by the CDC.

Other Information

WaterGuard is also available in tab form, the product was previously known as Klorin. This was originally produced by CARE.

Comments from the Community

1 Comment

  1. Emmy says:

    How do i get this water guard locally?

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