초록 ▼

Two layers of flexible material, each of which is resistant to the passage of fluids and microbes, include spacers between them, and are hermetically sealed, for maintaining reduced atmospheric pressure in the space between them. Open cell foam supported in the space is compressed by the layers unti

Two layers of flexible material, each of which is resistant to the passage of fluids and microbes, include spacers between them, and are hermetically sealed, for maintaining reduced atmospheric pressure in the space between them. Open cell foam supported in the space is compressed by the layers until one of the layers is torn, upon which the resulting increase in atmospheric pressure in the space allows the foam to resile, increasing the space between the layers as a warning to the user of the break. An electric switch which is responsive to pressure change is in communication with the space to also signal a warning of the break.

대표청구항 ▼

A septic barrier covering consisting of: a first layer of flexible material, said first layer being resistant to passage of water, air and microbes through said first layer, a second layer of flexible material, said second layer being resistant to passage of water, air and microbes through said seco

A septic barrier covering consisting of: a first layer of flexible material, said first layer being resistant to passage of water, air and microbes through said first layer, a second layer of flexible material, said second layer being resistant to passage of water, air and microbes through said second layer, means for spacing, supported between said first and second layers for spacing said second layer from said first layer, said first and second layers having space between them resulting from said means for spacing, said first and second layers being hermetically sealed for maintaining reduced atmospheric pressure in said space between said first and second layers, and outside said space (70, 156) between said first and second layers, said covering including; a hollow expandable patch (26, 132, 158, 262) on said first layer, compressible means (54, 158, 250) mounted in said hollow expandable patch for indicating an increase in reduced atmospheric pressure between said first and second layers, in passageway communication with said space between said first and second layers.