Research Article

Comprehensive Risk Assessment of Health-Related Hazardous Events in the Drinking Water Supply System from Source to Tap in Gaza Strip, Palestine

Table 6

Assessment of hazardous events in the drinking water at houses by seven raters.

HazardHazardous eventLikelihood avg (SD)Severity avg (SD)Risk level avg (SD)

MicrobialLow level of disinfection below the recommended limit3.87 (0.98)4.02 (0.92)16.38 (6.93) (very high risk)

Chemical and microbialExcessive algal formations inside of desalinated water storage tank3.62 (1.05)3.82 (1.07)14.82 (6.96) (high risk)

MicrobialThe drinking water tank is not periodically washed with chlorine and soap2.07 (1.25)2.32 (1.42)6.48 (7.24) (medium risk)

Chemical, physical, and microbialHand washing is not practiced before filling the drinking water storage tank2.33 (1.25)1.74 (0.78)4.91 (4.47) (low risk)

MicrobialThe desalinated water storage tank made of opaque plastic2.27 (1.37)1.47 (0.68)4.15 (4.34) (low risk)

MicrobialWater discontinuity or stored for an extended period inside the desalinated water storage tank2.27 (0.88)1.47 (0.70)3.74 (3.18) (low risk)

MicrobialThe area around drinking water storage tank is unclean and has an animal or birds access1.39 (0.93)1.56 (2.23)3.28 (5.51) (low risk)

ChemicalThe desalinated water storage tank made of corrosive metal1.37 (0.92)1.51 (1.23)3.17 (5.49) (low risk)

Chemical and microbialDesalinated water is mixed with nondesalinated water1.46 (0.80)1.58 (1.01)3.08 (4.02) (low risk)

MicrobialDrinking water storage tank is sited close to a toilet1.33 (0.89)1.42 (1.10)2.85 (5.28) (low risk)

Chemical, physical, and microbialPresence of foreign objects inside of desalinated water storage tank1.38 (0.73)1.50 (0.95)2.74 (3.65) (low risk)

Chemical, physical, and microbialThe cap of the desalinated water tank is absent or partially opened1.38 (0.73)1.46 (0.86)2.61 (3.34) (low risk)

MicrobialChildren get drinking water directly from the tank tap by their mouths1.30 (0.88)1.31 (0.89)2.46 (4.70) (low risk)

MicrobialThe drinking water storage tank is leaking1.19 (0.67)1.25 (0.83)2.03 (3.74) (low risk)

MicrobialThe drinking water storage container sited at ground level1.20 (0.74)1.15 (0.58)1.80 (3.23) (low risk)

MicrobialSpilled water accumulates around the drinking water storage tank1.18 (0.65)1.14 (0.49)1.66 (2.47) (low risk)

Chemical and microbialThe water storage tank used to store other liquids other than desalinated water1.09 (0.46)1.14 (0.70)1.56 (2.86) (low risk)

ChemicalA high level of overdosing of treatment chemicals (such as chlorine)1.01 (0.09)1.01 (0.12)1.03 (0.27) (low risk)

Risk level = likelihood ∗ Severity