| Roll | Atmosphere Type | Notes |
| 1 | Managed Atmosphere | Has lived in a domed city, star base, etc, because external atmosphere is unbreathable. Conditions within the protected environment are carefully controlled and monitored to maximize favourable factors. There is a fairly good cance that the atmosphere is maintained at a pressure significantly below 760mm Terran standard. This minimizes the effects of a sudden decompression from blowouts. |
| 2-3 | Low Pressure | Pressure under 500mm. Will have expanded lung capacity and can breathe effectively when oxygen pressure in the lungs is as low as 40mm IPP. When atmospheric pressure exceeds 1000mm excessive fatigue will occur. |
| 4-5 | Low Pressure w/ contaminants | As above, except there are significant concentrations of dust or toxic gases. 4) Will evidence greater tolerances of such contaminants than normal for off-planet types of the same or similar races. Or 5) lives in a managed atmosphere is highly skilled in the use of breathing aparatus, protective clothing and recognition of hostile conditions and has some minor tolerance of outside conditions. |
| 6-13 | Standard Pressure | Pressure of 500mm to 1000mm. |
| 14-15 | Standard Pressure w/ contaminants | 14 / 15 as, 4 / 5 above. |
| 16-17 | Moderately High Pressure | Pressure up to 2000mm. Low pressure atmospheres are not particularly comfortable, and fatigue may set in quickly in low oxygen environments. |
| 18 | Moderately High Pressure w/ contaminants | Have a 50% chance of higher tolerance levels to contaminants. |
| 19 | High Pressure | Pressures in excess of 2000mm. Low pressure atmospheres are distinctly disagreeable, while standard atmospheres are not comfortable. There is a 75% chance of contaminants, and a 50% chance for higher tolerance levels. |
| 20 | Exotic atmospheres | Very unusual concentrations of constituent atmospheric gases occur on the home world. There is a 50% chance that you are adapted to these conditions. |
