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.
Iâve been saying for years that I needed to do something about our mantel. Only 7 inches deep, to be exact! If you are someone who likes to decorate your mantel with each season, then you understand why this is such a problem. You canât put much on only 7 inches!