Acoustics + Vibration

Healthcare Acoustics

Essential Advice for Healthcare Designers and Owners

5 THINGS TO KNOW....

Acoustic considerations in the FGI guidelines go well beyond sound isolation. In fact, the core section of the FGI Guidelines for Hospitals that addresses acoustic design (1.2-6.1), includes criteria for:

FGI also touches on alarm fatigue, sound masking, helipad noise, and a range of other requirements. Each consideration warrants some assessment, and their impacts are rarely independent of one another.

In the Hospital Guidelines alone, the terms noise, acoustics, speech privacy, and vibration appear an additional 250 times outside of the core acoustic design sections. Solutions to address these considerations can impact early design decisions, such as building siting and massing, unit layouts, and staff workflow. During later design phases, noise and vibration solutions often affect interior finishes, interior assemblies, façade constructions, and building systems. These design approaches require deliberate and early coordination among caregivers, facility managers, and the design team.

While the FGI Guidelines provide a comprehensive framework to address acoustic considerations in a healthcare setting, they are nonetheless guidelines. Like any aspect of architectural design, criteria and regulations are goalposts – they are not a substitute for good design. The correct solution to achieve a set of criteria will be shaped by exceptions, design constraints, existing conditions, construction phasing, institutional preferences, budget, flexibility, and innumerable other factors. Making wise choices in these situations requires a firm understanding of the underlying impact that design decisions have on patients and caregivers.

Patient outcomes and privacy are paramount when addressing acoustics in a healthcare environment. However, it’s important to understand the impact that excessive noise can have on families and caregivers. In many cases, family members are spending considerable time in waiting rooms, patient rooms, and amenity spaces, patiently awaiting news about a loved one. They are likely under incredible stress, and exposure to excessive noise and overheard conversations only adds to their anxiety. Commotions and unfamiliar institutional noises can have the same effect.

Meanwhile, caregivers, who are working some of the most stressful jobs imaginable, can also be affected by excessive noise. Chronic noise exposure generates repeated stress responses, which lead to fatigue and reduced performance; this is true even for caregivers who otherwise thrive in a high-pressure healthcare setting. Additionally, noise in a clinical setting increases the risk of medical errors. Examples include a caregiver missing critical bioacoustics cues from patients or mishearing spoken instructions from a coworker.

Finally, environmental noise emitted by healthcare facilities can negatively impact the surrounding community. With these considerations in mind, it’s critical to consider the acoustic environment from the perspective of patients, families, caregivers, and the community.

In today's shifting healthcare landscape, providers must deal with increasingly complex facilities, new delivery models, and mounting industry pressures.

Financial Pressure: The acoustic environment directly impacts HCAHPS scores and online ratings, which affect hospital funding.
Staff Shortages: Excessive noise adds unnecessary stress to overworked caregivers.
Expanding Compliance Requirements:
- Modern healthcare facilities are being designed to comply with sustainability requirements in LEED, WELL, and other programs that contain acoustic performance and commissioning requirements.
- Cutting-edge procedures and equipment are leading to increasingly stringent vibration requirements in ORs, imaging suites, and clinical labs.
Outpatient Care: Healthcare providers are increasingly pushing care to community-based outpatient facilities.
- Facilities are being retrofitted into buildings that weren’t designed to accommodate healthcare acoustics.
- Noise from ambulances, increased traffic, helicopters, and rooftop equipment are problematic for nearby residential properties.

These acoustic considerations impact the immediate success of the project and can offer long-term benefits for healthcare systems.

Be wary of published sound isolation ratings for headwalls and other packaged systems. Whenever possible, seek out the original test report that describes the conditions under which the stated performance was achieved. Manufacturers will often test headwalls with outlet backers, additional insulation, interstitial layers, acoustic sealant, and minimal service penetrations. It quickly becomes clear that many of these provisions involve:

A. Non-standard product options

B. Installation procedures that aren't practical to implement across several hundred patient rooms

C. Unrealistic field conditions

Further, these ratings often only apply to the system’s main service panels. The headwalls are often coupled with poorly sealed infrastructure plenums located above the plane of the ceiling tile. These issues are especially challenging for patient rooms separated by back-to-back headwalls.

Armed with more realistic expectations for the headwall’s acoustic performance, you can decide what other supplemental provisions might be needed. These may include sound masking, selected headwall enhancements, additional insulation, barrier materials, or interstitial layers of wallboard.

Some of the most critical decisions regarding acoustics are made during a project’s earliest stages. For example, the cost and complexity of solutions to address existing noise from rail lines, roadways, airports, and industrial land uses can be dramatically impacted by the building’s siting and massing. The same is true for environmental noise emitted by the healthcare facility, such as rooftop equipment, louvers, helipads, and emergency vehicles.

Meanwhile, carefully considered building layouts and workflows will locate noise-sensitive spaces at an appropriate distance from noise-generating spaces. Typical areas of concern typically include public areas, mechanical rooms, rehab gyms, and kitchens. By avoiding problematic adjacencies, designers can sidestep the need for expensive and complex provisions for sound isolation.

These acoustic considerations require thoughtful coordination with a multitude of competing requirements, which are often critical. However, while acoustics may not be the deciding factor, it pays to understand how these design decisions will affect the need for supplemental acoustic solutions. So, while early consideration of a building’s massing and layout may not avoid all problematic adjacencies, it allows the team to carry an appropriate budget to address known issues.

Still want to learn more? Here's a bonus tip:

Sound Transmission Class (STC) is one of the most familiar acoustic metrics in the AEC industry and one of the primary metrics in the FGI guidelines. It is a single number rating that summarizes the sound isolation of a single building element under ideal laboratory conditions. Critically, STC ratings do not consider how an assembly performs in the field:

The composite isolation of an assembly made up of multiple constructions (e.g. a partition with a door, window, headwall, etc.)
Sound that may bypass the assembly via the floor, ceiling, or curtain walls.
Field conditions that may degrade the element’s acoustic performance (e.g. penetrations and airtightness)
How the transmitted sound reacts with the acoustic environment on each side of the assembly.
Whether transmitted sound is actually audible, disruptive, or intelligible (in the case of speech). This factor is primarily determined by building system noise levels or sound masking systems.

A single number rating is simply not able to take all of these considerations into account. Closer analysis is required to ensure assemblies will perform as expected and provide a peaceful and private environment for patients, caregivers, and families.

Want to learn more? Auxia Design offers an AIA HSW accredited course on Healthcare Acoustics and many other topics.