A fluid analysis apparatus for containing and analyzing a fluid sample, said fluid analysis apparatus comprising: a cell body assembly having first and second distinct portions (15, 16) in fluid communication with one another, each of said first and second portions (15, 16) having respective first and second ends (22, 24; 32, 34), with respective first ends (22, 32) of said first and second portions (15, 16) being operably disposed in spaced facing relationship with one another, said first portion including a fluid sample inlet bore, a first fluid sample outlet bore, and a radiant energy inlet bore, and said second portion including a fluid sample analysis chamber in axial operable alignment with said radiant energy inlet bore of said first portion, and a second fluid sample outlet bore in operable alignment with said first fluid sample outlet bore, the analysis chamber being defined by an axial bore axially extending through said second portion from said first end to said second end thereof; a first resilient gasket interposed between said first ends (22, 32) of said first and second portions (15, 16), said first resilient gasket including a first radiant energy aperture in operable alignment with said radiant energy inlet bore of said first portion and said fluid sample analysis chamber of said second portion, a second fluid sample outlet aperture in operable alignment with respective said first and second fluid sample outlet bores (28, 38) of said first and second portions (15, 16), and a fluid sample transfer groove extending from a fluid sample inlet portion of said first resilient gasket that is in axial operable alignment with said fluid sample inlet bore of said first portion to said first radiant energy aperture, the fluid analysis apparatus being characterised in that a radiant energy guiding member is disposed in said fluid sample analysis chamber and forms a tube radially disposed about a central axis thereof, the radiant energy guiding member being formed from substantially transparent materials, and in that said fluid sample transfer groove extends only partially through a thickness dimension of said first resilient gasket such that incoming radiant energy does not leak into a side wall of the radiant energy guiding member, and in that said thickness dimension is selected to define a desired transfer zone dimension based on a calculated amount of radiant energy loss in passing through the first radiant energy aperture, wherein the resilient gasket is formed from a substantially opaque material. a cell body assembly having first and second distinct portions (15, 16) in fluid communication with one another, each of said first and second portions (15, 16) having respective first and second ends (22, 24; 32, 34), with respective first ends (22, 32) of said first and second portions (15, 16) being operably disposed in spaced facing relationship with one another, said first portion including a fluid sample inlet bore, a first fluid sample outlet bore, and a radiant energy inlet bore, and said second portion including a fluid sample analysis chamber in axial operable alignment with said radiant energy inlet bore of said first portion, and a second fluid sample outlet bore in operable alignment with said first fluid sample outlet bore, the analysis chamber being defined by an axial bore axially extending through said second portion from said first end to said second end thereof; a first resilient gasket interposed between said first ends (22, 32) of said first and second portions (15, 16), said first resilient gasket including a first radiant energy aperture in operable alignment with said radiant energy inlet bore of said first portion and said fluid sample analysis chamber of said second portion, a second fluid sample outlet aperture in operable alignment with respective said first and second fluid sample outlet bores (28, 38) of said first and second portions (15, 16), and a fluid sample transfer groove extending from a fluid sample inlet portion of said first resilient gasket that is in axial operable alignment with said fluid sample inlet bore of said first portion to said first radiant energy aperture, the fluid analysis apparatus being characterised in that a radiant energy guiding member is disposed in said fluid sample analysis chamber and forms a tube radially disposed about a central axis thereof, the radiant energy guiding member being formed from substantially transparent materials, and in that said fluid sample transfer groove extends only partially through a thickness dimension of said first resilient gasket such that incoming radiant energy does not leak into a side wall of the radiant energy guiding member, and in that said thickness dimension is selected to define a desired transfer zone dimension based on a calculated amount of radiant energy loss in passing through the first radiant energy aperture, wherein the resilient gasket is formed from a substantially opaque material.