Meyer-Falcke A, Rack R, Eichwede F, Jansing P J
Institute of Occupational Medicine, Düsseldorf, Germany.
Eur J Anaesthesiol. 1994 Sep;11(5):407-11.
The minimum and maximum sound pressure levels (Lmin, Lmax) were measured, and the energy equivalent sound pressure level (Leq) and the impulse rated Leq (LAlm) were ascertained in the surgical intensive care unit and the anaesthetic and recovery room. Frequency analyses were also made of the noise from various pieces of equipment. The LAlm was never below 60 dB(A)--the wake-up threshold in man--comprising strong narrow-band impulses with Lmax more than 100 dB(A) primarily from instrument alarms. When several instruments were alerted at the same time, a broad-band noise resulted which was based on their various spectral peaks. Whilst the maximum sound level of the technical equipment was high, it was surpassed by avoidable background noise caused by the staff (e.g. falling bucket lid: 94.7 dB(A)). No relationship was found between acoustic parameters and intended type of anaesthesia or surgery. Sound level was low in dangerous situations and high during routine work.
测量了最小和最大声压级（Lmin、Lmax），并在外科重症监护病房以及麻醉和恢复室确定了能量等效声压级（Leq）和脉冲额定Leq（LAlm）。还对各种设备发出的噪声进行了频率分析。LAlm从未低于60 dB（A）（人体唤醒阈值），主要由仪器警报产生的Lmax超过100 dB（A）的强烈窄带脉冲组成。当多个仪器同时发出警报时，会产生基于其不同频谱峰值的宽带噪声。虽然技术设备的最大声级很高，但工作人员造成的可避免背景噪声（如掉落的桶盖：94.7 dB（A））超过了该声级。未发现声学参数与预期的麻醉或手术类型之间存在关联。危险情况下声级较低，日常工作期间声级较高。
