The vacuum tube in a CRT can implode if it is broken or punctured. The surrounding air will rush violently into the unsealed vacuum in the CRT, spraying broken glass in every direction. Color CRTs may contain mercury or other potentially toxic materials.
Instructions. Build a hearth for a fireplace that is 16 inches deep, according to This Old House writer Harry Sawyers. This is the standard requirement for municipalities and homeowner associations. The hearth should also extend a minimum of eight inches on either side of the fireplace.
One frequently overlooked aspect of sizing a kitchen sink is the depth of the sink. Sinks start out at a depth of 8 inches and can get as deep as 12 or 15 inches for specialty sinks. Deep sinks can hold more dishes for busy cooks, but they can also be difficult to reach the bottom of for shorter homeowners.