Noise may cause hearing damage and delayed growth and development in newborns in neonatal intensive care units. Hence, it is necessary to reduce noise in these environments. Training and use of visual signs have been investigated as the interventional strategies with the aim of reducing noise level and exposure in neonatal intensive care units. This quasi-experimental study (before and after design) was conducted in the NICU of Birjand University of Medical Sciences Hospital (BUMSH NICU). According to ISO9612 standard, equivalent and maximum noise level in the NICU was measured by a calibrated sound level meter TES model 1358C at various stations during different shifts. Subsequently, the training and visual signs (flags and posters) were utilized as the interventions and SPSS version 18 was used for data analysis. The average equivalent and maximum noise level were calculated between 43.5–69.2 and 55.3–79.2 dBA, respectively, which is above the standards recommended by the American Academy of Pediatrics (AAP). Staff conversation, equipment and alarms were among the main sources of noise pollution. The equivalent noise level showed meaningful reduction before and after the interventions (personnel training and visual signs usage) at night. Noise in our NICU was greater than the recommended sound levels of 45 dBA. However, training and visual signs interventions seemed effective in reducing noise levels, particularly during the night shift. Since conversation was identified as the main noise source, future research is recommended to determine personality traits in healthcare professionals and promote a culture of silence.

噪音可能会导致新生儿重症监护病房的听力受损，并延缓新生儿的生长发育。因此，有必要减少这些环境中的噪声。为了减少噪音和降低新生儿重症监护室的暴露水平，已经研究了视觉标志的训练和使用作为干预策略。这项准实验研究（设计之前和之后）是在Birjand医学大学医院的重症监护病房（BUMSH NICU）中进行的。根据ISO9612标准，在不同的班次中，通过校准的声级计TES型1358C在不同的工位上测量了NICU中的等效和最大噪声水平。随后，将培训和视觉标志（旗帜和海报）用作干预措施，并使用SPSS 18版进行数据分析。平均等效声级和最大噪声级分别在43.5–69.2和55.3–79.2 dBA之间计算，高于美国儿科学会（AAP）推荐的标准。员工交谈，设备和警报是噪声污染的主要来源。当晚干预（人员培训和视觉标志使用）前后，等效噪声水平显示出有意义的降低。我们的重症监护病房中的噪音大于建议的45 dBA声级。但是，培训和视觉信号干预似乎可以有效降低噪音水平，尤其是在夜班期间。由于谈话被确定为主要的噪声源，因此建议进行进一步的研究以确定医疗保健专业人员的人格特质并促进沉默文化。