Sample dish and compressed gas microbial test unit

1. A sample dish, comprising:

a base extending in a direction along a longitudinal axis between opposed first and second surfaces and extending radially outward in a direction orthogonal to the longitudinal axis, the base comprising an outer periphery extending between the opposed first and second surfaces, an opening extending through the base between the opposed first and second surfaces, and an inner periphery extending between the opposed first and second surfaces and defined by the opening;

an outer side wall at the outer periphery of the base, the outer side wall extending from the first surface of the base in a direction along the longitudinal axis;

an inner side wall at the inner periphery of the base, the inner side wall extending from the first surface of the base in a direction along the longitudinal axis; and

at least one channel at the second surface of the base, the at least one channel extending between the outer periphery and the inner periphery.

2. The sample dish of claim 1 , wherein the opening and inner side wall are concentric with the outer periphery.

3. The sample dish of claim 1 , wherein the at least one channel extends from the outer periphery to the inner periphery.

4. The sample dish of claim 3 , wherein the at least one channel extends linearly from the outer periphery to the inner periphery.

5. The sample dish of claim 1 , wherein the first surface of the base, the outer side wall, and the inner side wall form a receptacle configured to hold a microbial growth substrate.

6. The sample dish of claim 5 , further comprising at least one partition wall extending from the first surface of the base in a direction along the longitudinal axis, the at least one partition wall arranged to divide the receptacle into two or more sub-regions.

7. A microbial test unit, comprising:

a housing extending along a longitudinal axis between a first end and a second end, the housing defining an internal cavity configured to contain a sample dish;

an outlet passing through the housing at the second end of the housing;

a cuff extending along the longitudinal axis into the internal cavity from the outlet, the cuff being an open-ended member configured to extend through an opening of the sample dish and provide fluid communication between the internal cavity and the outlet; and

a plurality of ribs projecting into the internal cavity along the longitudinal axis, each of the plurality of ribs extending between the cuff and an inner surface of the housing, each of the plurality of ribs configured to mate with a respective channel of the sample dish.

8. The microbial test unit of claim 7 , wherein each of the plurality of ribs radially extends from the cuff to the inner surface of the housing.

9. The microbial test unit of claim 8 , further comprising a flow channel provided between respective ones of the plurality of ribs, the flow channel radially extending between the cuff and the inner surface of the housing.

10. The microbial test unit of claim 9 , wherein the cuff comprises an opening configured to provide fluid communication between the flow channel and the outlet.

11. A microbial test system, comprising:

the microbial test unit of claim 7 ; and

a sample dish, comprising:

a base extending in a direction along the longitudinal axis between opposed first and second surfaces and extending radially outward in a direction orthogonal to the longitudinal axis, the base comprising an outer periphery extending between the opposed first and second surfaces, an opening extending through the base between the opposed first and second surfaces, and an inner periphery extending between the opposed first and second surfaces and defined by the opening;

an outer side wall at the outer periphery of the base, the outer side wall extending from the first surface of the base in a direction along the longitudinal axis; and

an inner side wall at the inner periphery of the base, the inner side wall extending from the first surface of the base in a direction along the longitudinal axis.

12. The microbial test system of claim 11 , wherein:

the sample dish comprises a plurality of channels at the second surface of the base, each of the channels extending between the outer periphery and the inner periphery, each of the channels configured to mate with a respective one of the plurality of ribs.

13. The microbial test system of claim 12 , wherein

the microbial test unit further comprises a flow channel provided between respective ones of the plurality of ribs, the flow channel radially extending between the cuff and the inner surface of the housing;

the second surface of the base collectively forms a passage with the flow channel; and

the cuff comprises an opening configured to provide fluid communication between the passage and the outlet.

14. The microbial test unit of claim 7 , wherein:

the internal cavity comprises a decompression region for decompressing compressed gas input to the internal cavity and a sampling region in fluid communication with the decompression region for containing the sample dish, the decompression region and the sampling region defining a flow path through the internal cavity;

an inlet is at the first end of the housing proximate the decompression region;

the outlet is proximate the sampling region; and

the cuff extends along the longitudinal axis into the sampling region from the outlet, the cuff configured to provide fluid communication between the sampling region and the outlet.

15. The microbial test unit of claim 14 , wherein each of the plurality of ribs radially extends from the cuff to the inner surface of the housing.

16. The microbial test unit of claim 15 , further comprising a flow channel provided between respective ones of the plurality of ribs, the flow channel radially extending between the cuff and the inner surface of the housing.

17. The microbial test unit of claim 16 , wherein the cuff comprises an opening configured to provide fluid communication between the flow channel and the outlet.

18. A microbial test system, comprising:

the microbial test unit of claim 14 ; and

a sample dish, comprising:

a base extending in a direction along the longitudinal axis between opposed first and second surfaces and extending radially outward in a direction orthogonal to the longitudinal axis, the base comprising an outer periphery extending between the opposed first and second surfaces, an opening extending through the base between the opposed first and second surfaces, and an inner periphery extending between the opposed first and second surfaces and defined by the opening;

an outer side wall at the outer periphery of the base, the outer side wall extending from the first surface of the base in a direction along the longitudinal axis; and

an inner side wall at the inner periphery of the base, the inner side wall extending from the first surface of the base in a direction along the longitudinal axis.

19. A microbial test system, comprising:

a microbial test unit, comprising:

a housing extending along a longitudinal axis between a first end and a second end, the housing defining an internal cavity configured to contain a sample dish;

an outlet passing through the housing at the second end of the housing; and

a cuff extending along the longitudinal axis into the internal cavity from the outlet, the cuff being an open-ended member configured to extend through an opening of the sample dish and provide fluid communication between the internal cavity and the outlet; and

a sample dish, comprising:

a base extending in a direction along the longitudinal axis between opposed first and second surfaces and extending radially outward in a direction orthogonal to the longitudinal axis, the base comprising an outer periphery extending between the opposed first and second surfaces, an opening extending through the base between the opposed first and second surfaces, and an inner periphery extending between the opposed first and second surfaces and defined by the opening;

an outer side wall at the outer periphery of the base, the outer side wall extending from the first surface of the base in a direction along the longitudinal axis; and

an inner side wall at the inner periphery of the base, the inner side wall extending from the first surface of the base in a direction along the longitudinal axis.

20. The microbial test system of claim , wherein:

the internal cavity comprises a decompression region for decompressing compressed gas input to the internal cavity and a sampling region in fluid communication with the decompression region for containing the sample dish, the decompression region and the sampling region defining a flow path through the internal cavity;

an inlet is at the first end of the housing proximate the decompression region;

the outlet is proximate the sampling region; and

the cuff extends along the longitudinal axis into the sampling region from the outlet, the cuff configured to provide fluid communication between the sampling region and the outlet.