BS/EN 16603-34-2014 pdf download.Space engineering Part 34 : Environmental control and life support ( ECLS ).
4.4.2.2.6 Add inert diluent gas to atmosphere
a. Addition of inert diluent gas (for example nitrogen) into the pressurized volume shall be provided at a rate capable of maintaining the atmospheric pressure within the control range.
b. Addition of inert diluent gas (for example nitrogen) into the atmosphere shall be provided at a rate capable of atmospheric restoration after decompression of the habitable volume.
c. When adding inert diluent gas (for example nitrogen) into the atmosphere the levels of anoxic or hypoxic zones in the accessible volume shall be specified.
d. The limits for pressure adjustments, decompression, compression and re-compression shall be specified.
e. Means to manage pressure change rates within the specified limits shall be provided.
4.4.2.2.7 Add oxygen to atmosphere
a. Addition of gaseous oxygen into the atmosphere shall be provided at a rate capable of maintaining the oxygen partial pressure in the accessible volume within the specified range.
b. Addition of gaseous oxygen into the atmosphere shall be provided at a rate capable of restoring the atmospheric condition after decompression of the accessible volume.
C. Addition of oxygen shall not create risk of fire.
4.4.2.3 Control thermal nominal condition
4.4.2.3.1 Maintain thermal nominal condition:
a. The limits of the atmosphere effective temperature in the habitable volume shall be specified.
NOTE The atmosphere effective temperature is a combination of dry bulb temperature, wet bulb
temperature and ventilation.
4.4.2.3.2 Maintain temperature
a. The atmosphere dry bulb temperature in the habitable volume shall be selectable within the operational range.
b. The accuracy for the stabilized dry bulb temperature in the habitable volume shall be specified.
c. Removal of excess sensible heat from the atmosphere or addition of sensible heat into the atmosphere shall be provided at a rate capable of maintaining the atmosphere temperature within the specified range.
d. The points of measurement for the dry bulb temperature shall be representative for the habitable volume situation.
4.4.2.3.3 Maintain atmosphere humidity
a. The range for the atmosphere relative humidity in the habitable volume shall be specified.
b. The range for the atmosphere dew point in the pressurized volume shall be specified.
NOTE Relative humidity is in relation to human comfort evaluation; dew point limits are intended to prevent condensation. Both measurements indicate the water vapour content of the atmosphere.
4.4.2.3.4 Monitor atmosphere humidity
a. The range and the accuracy to monitor the atmosphere relative humidity in the habitable volumes shall be specified.
b. The range and accuracy of the atmosphere dew point temperature to be monitored in the pressurized volumes shall be specified.
c. Water vapour shall be removed from or added to the pressurized volume atmosphere at a rate capable of maintaining the specified range.
4.4.2.3.5 Circulate atmosphere
a. Ventilate habitable volume: atmosphere velocities in the habitable volume shall be maintained within the specified air velocity ranges, adapted to total atmospheric pressure situation.
b. Gas velocity ranges can differ between habitable and non-habitable volume.
c. Exchange of atmosphere between pressurized volumes: atmosphere exchange between connected pressurized volumes shall be specified.
d. Monitor ventilation and atmosphere exchange: Location of ventilation and atmosphere exchange monitoring shall be specified.
NOTE Since atmosphere circulation in the habitable volume is intended to maintain thermal nominal condition and atmospheric composition, the previous requirements are included to control of atmosphere circulation.
4.4.2.4 Control oxygen partial pressure
4.4.2.4.1 Maintain oxygen partial pressure
a. The limits for the oxygen partial pressure in the atmosphere of habitable volume shall be specified.
4.4.2.4.2 Monitor oxygen partial pressure
a. The range and accuracy to monitor the atmosphere oxygen partial pressure shall be specified.
4.4.2.4.3 Add oxygen into the atmosphere
a. For adding oxygen into the atmosphere, requirements in 4.4.2.2.7 shall apply.
4.4.2.5 Control carbon dioxide partial pressure
4.4.2.5.1 Maintain low carbon dioxide partial pressure
a. The threshold values for the carbon dioxide partial pressure in the atmosphere of habitable volume shall be specified.
4.4.2.5.2 Remove carbon dioxide from atmosphere
a. Removal of carbon dioxide from the atmosphere shall be provided at a rate capable of maintaining the carbon dioxide partial pressure below the specified threshold value.
4.4.2.5.3 Monitor carbon dioxide partial pressure
a. The range and accuracy for the monitoring of the atmosphere carbon dioxide partial pressure shall be specified.
4.4.2.6 Control carbon monoxide partial pressure
4.4.2.6.1 Maintain low carbon monoxide partial pressure
a. The threshold values for the carbon monoxide partial pressure in the atmosphere of the accessible volume shall be specified.
4.4.2.6.2 Remove carbon monoxide from atmosphere
a. Removal of carbon monoxide from the atmosphere shall be provided at a rate capable of maintaining the carbon monoxide partial pressure below the specified threshold value.
4.4.2.6.3 Monitor carbon monoxide partial pressure
a. The range and accuracy for monitoring the atmosphere’s carbon monoxide partial pressure shall be specified.
4.4.2.7 Control trace gases and odour.BS/EN 16603-34-2014 pdf download.