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Figure 13.1
Design criteria governing low flush-volume WC performance |
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Vaal Potteries cistern, produced in South Africa. The ceramic cistern was adopted for the site trials due to the fire risk caused by candles placed on a plastic cistern and also as no indigenous manufacture of sanitary fittings exists in Botswana and Lesotho. The plastic and ceramic cistern fitted bowls (termed the Mark III and 'field' Mark III WC, respectively) were compared with the original Twyfords BS1213 WC (termed Mark 0) for flush volumes between 3 and 9 litres, as shown in Figures 13.3 and 13.4. |
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Figure 13.3 illustrates the 0.85 specific gravity multiple ball test. The Mark III WCs performed similarly, and even at 3 litres |
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Figure 13.2
Bowl performance for solid and fluid contamination performance |
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