原文：“The dryness of the steam is of vital importance to the performance of any steam sterilizer. Excess moisture may cause damp loads in porous materials and uneven temperature distributions in non-porous loads, particularly those containing a large number of small items such as ampoules. When steam is required to be in direct contact with the surface to be sterilized, such as in porous-load sterilizers, sterilising conditions may not be attained if the moisture contained in the steam supply is insufficient to prevent the steam from becoming superheated when expanding into the chamber.”
European Standards require that sterilizers be designed to operate with steam having a dryness value of not less than 0.9 when measured in accordance with the steam dryness test described in Part 3 of this SHTM. For metal loads, the dryness value should not be less than 0.95. In practice, problems are unlikely to occur if the dryness value lies between 0.9 and 1.0, if it is reasonably constant and if the pressure reduction through the final pressure-reducing system is of the order two to one.
译：蒸汽的干度对任何蒸汽灭菌器的性能都是至关重要的。过多的水分可能会导致多孔材料中的湿载荷和非多孔载荷中的温度分布不均匀，特别是那些包含大量小物品(如安瓿)的载荷。当要求蒸汽与待灭菌表面直接接触时，例如在多孔负载灭菌器中，如果蒸汽供应中所含的水分不足以防止蒸汽在膨胀进入腔室时过热，则可能无法达到灭菌条件。
欧洲标准要求灭菌器设计为在干燥值不低于0.9的蒸汽下运行，根据本SHTM第3部分中描述的蒸汽干燥试验进行测量。对于金属负载，干燥值不应低于0.95。在实践中，如果干燥值在0.9和1.0之间，如果它是合理恒定的，并且通过最终减压系统的减压量是2比1的数量级，则不太可能发生问题。
原文：Superheated steam is an unsuitable medium for moist heat sterilization and can cause failure to sterilise, scorching of textiles and paper and rapid deterioration of rubber. Superheat conditions within the load and chamber may result from adiabatic expansion, exothermic reaction or both.
European Standards require that the superheat in free steam at atmospheric pressure should not exceed 25℃C when measured by the superheat test described in Part 3 of this SHTM.
译：过热蒸汽是一种不适合用于湿热灭菌的介质，它会导致灭菌失败、纺织品和纸张烧焦以及橡胶的迅速变质。负载和腔室内的过热状况可能是由绝热膨胀、放热反应或两者同时引起的。
欧洲标准要求，在常压下，通过本SHTM第3部分中描述的过热度测试测量时，洁净蒸汽中的过热度不应超过25℃。
原文：Non-condensable gases (NCGs) are defined as gases which cannot be liquefied by compression under the range of conditions of temperature and pressure used during the sterilization process. Low levels of NCGs contained in steam supplied to sterilizers can markedly affect the performance of the sterilizer and the efficacy of the process, cause chamber overheat and lead to inconsistencies in the performance of air detectors and failure of the Bowie-Dick test (see Part 3). The major NCGs are air and carbon dioxide.
British and European Standards require that sterilizers be designed to operate with steam having a fraction of NCGs not exceeding 3.5% by volume when measured by the method described in the non-condensable gas test (see Part 3).
译：不可冷凝气体(NCGs)被定义为在灭菌过程中使用的温度和压力条件范围内不能通过压缩液化的气体。提供给灭菌器的蒸汽中含有NCGs，会显著影响灭菌器的性能和工艺效率，导致灭菌室过热，并导致空气探测器性能不一致和鲍伊-迪克测试失败(参见第3部分)。主要的NCGs是空气和二氧化碳。
英国和欧洲标准要求灭菌器设计为在不凝性气体测试(见第3部分)中描述的方法测量时，具有不超过3.5%体积的NCGs的蒸汽运行。
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