本powerpoint演示文稿首先简要概述了全球卫生挑战，并展示了一张地图，显示了千年发展目标的相对规模 根据 到2015年所需的安装数量。在重新思考卫生问题时，提出了alterna窝，即并排挖掘两个坑，并使用一个坑直到填满，然后切换到第二个坑。第二年结束后，第二个使用过的坑（坑2）将几乎满。是时候再次改变立场了。坑1的内容物现在将变成腐殖质。清空1号坑的内容物，并与花园土壤按同等比例混合，用于种植蔬菜。 或者将其储存在袋子中以备将来使用。

This powerpoint presentation begins by providing a brief overview of the global sanitation challenge and a map is presented showing the relative size of the MDG sanitation target for each country based on the number of installations required through to 2015. Rethinking sanitation, the Fossa alterna is presented, of digging two pits, side-by-side, and using one until full, then switching to the second pit. After the end of the second year the second used pit (pit 2) will be almost full. The time has come to change sides again. The contents of pit 1 will now have changed into humus. Empty the contents of pit 1 and mix in equal proportions with garden soil and use to grow vegetables. Alternatively store for future use in bags.