The production and transport of liquid and gaseous hydrocarbons have always been the object of studies to improve technologies and procedures, as they involve large volumes and high-value goods. There are several procedures, rules and regulations applied to the measurement of fluid flow, but its applicability may involve significant operating costs. The balance between requirements and costs led to the use of gauge pressure transmitters instead of absolute pressure gauges and assuming a constant atmospheric pressure value for parameterization of compensation algorithms. This solution simplifies the calibration process but can potentially impact measurement uncertainties because atmospheric pressure is not constant. This work quantifies these impacts and concludes that, for gas systems operating below 2000 kPa, the use of absolute pressure transmitters or the incorporation of in-line atmospheric pressure gauges is recommended. Above this value, the effects of atmospheric pressure variation do not have as much impact, but even in these cases the final uncertainty estimate of the measured gas volume must consider this source of additional uncertainties.

液态和气态碳氢化合物的生产和运输一直是改进技术和程序的研究对象，因为它们涉及大量和高价值的货物。有多种程序、规则和规定适用于流体流量的测量，但其适用性可能涉及大量运营成本。需求和成本之间的平衡导致使用表压变送器而不是绝对压力表，并假设一个恒定的大气压力值用于补偿算法的参数化。该解决方案简化了校准过程，但可能会影响测量的不确定性，因为大气压力不是恒定的。这项工作量化了这些影响并得出结论，对于在 2000 kPa 以下运行的气体系统，建议使用绝对压力变送器或结合在线大气压力表。高于此值，大气压力变化的影响不会有太大影响，但即使在这些情况下，测量气体体积的最终不确定性估计也必须考虑这个额外的不确定性来源。