Firm's role on the project: Conduct a two phased sound study to identify ways to decrease noise.
In healthcare settings, noise negatively effects patients and staff, and yet healthcare environments are notoriously noisy places. For St. Mary’s Hospital, creating a quieter experience was a main goal. As part of their Cardiac Care Unit addition to their existing hospital, Kahler Slater completed a two-phased Sound Study to help identify ways to decrease noise.
The first phase of the Sound Study was a multi-strategy approach to inform the flooring selection. There was a preconception that carpet would be the better choice because of sound absorption. The research team conducted a literature review, a comparative review of product manufacturers’ information and conducted field observations (recording noise levels and sources) of an existing inpatient unit. The researchers conducted more than 20 hours of field observations and collected over 50 hours of noise level data. They were measured at three different locations and the sound sources were categorized.
The study found peak and average noise levels exceeded the guidelines set by the World Health Organization. Peak levels measured 73dB, compared to the recommended levels of 40 dB during the day and 35 dB at night. A wide range of sound sources were observed– alarms, equipment moving through corridors, conversations, and many other sounds that contributed to excess noise on the unit.
Based on these findings, architectural solutions were designed to mitigate noise sources on the new unit, including locating family lounges and elevators separate from patient care areas, providing sound barriers between all patient walls, locating ice machines and printing devices in rooms, and using acoustic materials above corridor charting stations. Behavioral and operational strategies were also recommended to help implement a Culture of Quiet. Vinyl flooring was ultimately selected, which reduced the need for daily vacuuming among other benefits.
A year after occupancy of the new unit, Kahler Slater completed the post occupancy phase of the Sound Study, which included submission to St. Mary’s Hospital’s Institutional Review Board. The process is very intensive to ensure patient privacy is protected during the research. This phase including 30 hours of field observations in which sound levels were measured and 96 sound sources were observed. Sound levels and sources were compared to the levels and sources of the existing unit. They had different acuity levels, which was a limitation of the study, however there was a reduction in noise occurrences in three of the highest sound sources from the first study: noises related to the elevators, the ice machine and the vacuum. HCAHPS scores are currently 13.5% above the national average in quietness at night at St. Mary’s Hospital.