About Manholes & Odor Control Inserts in General
Some History for you:
The first manhole covers were actually
slabs of stone or pieces of wood that gave people the opportunity to
inspect covered ditches which conveyed sewage. This probably was in use for many
centuries…… approximately 3500 BC to 1750s AD. (Also, there were lots of ditches
not covered!) The Cloaca Maxima was one of the world's earliest
sewagesystems. Constructed in ancient Rome in order to drain local
marshes and remove the waste of one of the world's most populous cities, it
carried the effluent to the River Tiber which ran beside the city. It was
accessed from the side by tunnels not top openings.
The first top openings for sewers were called "Lamp holes" and their purpose was
(with some sort of light source) to look down into the sewer and see if it was
flowing. Further it provided a ventilation point for the sewer as it was early
recognized that sewers needed to breathe.
Cast Iron frames and covers were developed in the early 1800’s. The modern
manhole insert is a 1900s development and today several styles are offered. The
term “Manhole” was originally a seafarer’s term for the 24” diameter passageways
between decks on wooden sailing ships
The tubs (actual insert) are made of ABS, HDPE, or Stainless Steel.
Our OdorKnocker™ unit is made of 18 Gauge 304 Stainless Steel which is
hydraulically pressed to shape from a single sheet of SS. We do not weld as
welds may be weakened by the action of H2S. Our pressed unit has three (3)
reinforcing ribs as part of the bottom shape and it will stand a load test of
3000lbs or more. Some non SS units are known to break up from traffic vibrations
and actually fall into the sewer & block the flow.
The types of media being offered with units are Carbon, Oxidizing Granules,
Impregnated Granules, and our OdorKnocker™ iron based media which does not just
absorb H2S but actually converts it to Iron Pyrite or "Fools Gold" and is non-
hazardous at any point.Also, a MSDS is ALWAYS
furnished with our units
