‘Alarm fatigue’ is a term which refers to the problems experienced by healthcare providers (HCP) in critical care which are related to the excessive occurrence of alarm signals (auditory or visual) which can lead to important alarms being missed [[6], [7],8,13]. Reasons for missed alarms include excessive not-clinically-actionable alarms, the sheer noise and disruption caused by the way alarms typically sound, and problems of confusion between alarms which might be misunderstood, or simple masking (acoustic occluding) of one alarm by another [3]. Alarms are needed for patient monitoring and helpful in identifying early signs of a developing problem. It is worth to take steps to reduce the likelihood of mistakes due to alarms in the critical care environment (i.e., intensive care units, emergency rooms, operating theatres). The target is to ensure all alarms that are needed are functioning, true (i.e., actionable), audible (unmasked by other alarms going off at the same time), and actionable (i.e., confusion is kept to a minimum). Below, we will elaborate more on five selected target areas that healthcare providers in critical care can benefit from: [...]

Perceived acoustic environments, or soundscapes, of intensive care units (ICUs) can be stressful for patients. We developed an approach to enhance ICU soundscapes with soundscape interventions. Compositions of Natural, Human, or Technological sounds were designed to establish three types of sonic ambiances: Comfortable, Pleasurable, or Stimulating. The objective was to investigate the approach's effectiveness in a real-world ICU environment. In a controlled experiment conducted in a single-patient, sound-proofed ICU room, 26 healthy participants were exposed to simulated ICU soundscapes, including patient monitor alarm sounds and mechanical ventilator sounds. Nine soundscape interventions were played via speakers. Perceived pleasantness and eventfulness of resulting soundscapes and experienced pleasure and arousal of listeners were evaluated with questionnaires. Physiological indicators of stress were measured using electrocardiograms (ECGs). Pleasurable and Stimulating interventions significantly increased perceived pleasantness and eventfulness when introduced to the simulated ICU soundscape. Comfortable interventions had no significant effect, suggesting that Pleasurable and Stimulating ambiances better aligned with participants’ needs relative to the simulated soundscape. It emphasized the need to tailor ICU interventions to the preexisting acoustic environment and sound-related needs of listeners, such as comfort, distraction or reassurance. Participants reported positive emotional states while listening to the soundscape interventions, indicative of positive listener experiences. Preliminary insights regarding changes in heartrate variability hinted that soundscape interventions could potentially contribute to reduced stress levels. The effectiveness of interventions depended on their featured sound categories, highlighting the importance of personalization. Overall, our approach was found effective, showing promise for creating listener-centric, restorative soundscapes during ICU stays.

While developments in medical device technology improve clinical monitoring by incorporating more sensitive features, they also lead to high ICU noise levels due to the increased number of alarms. This study seeks to understand the effect of critical alarms from various medical devices, such as patient monitors, infusion pumps, and mechanical ventilators, on overall sound pressure levels and existing noise metrics in the Adult ICU of Erasmus Medical Center. The study was conducted for ten days, during which two patients were admitted, and their usual care routines were maintained. A calibrated class II sound level meter was positioned above the patient’s head to continuously record acoustical data in one of the single-patient ICU rooms. Acoustic parameters, including LAf, LCPeak, LAeq, were measured, and alarm logs were retrieved from the alarm management database. Patient monitor alarms were also analyzed by severity, as different alarms have distinct acoustic characteristics. Initial findings indicate that equivalent sound pressure levels exceed recommended thresholds, however, with only a limited contribution of alarms. Future research should focus on a more comprehensive and human-centered acoustic characterization of this critical environment, so that relevant associations between health outcomes and sound environment can be made.

In an earlier study, we explored the intersection between human perception of sound, Machine Listening, and their potential societal and environmental impact with experts in computer science, art and philosophy, design, and ethics. As a follow-up work, we explored SoundAI applications through two MSc design student projects at TU Delft on the topics of building cultural bonds by generating new community soundscapes and increasing awareness on biodiversity by focussing on other-than-human noise sensitivity. This paper presents these two use cases with societal, environmental, and ethical considerations, and suitable AI techniques. The proposed applications manifest themselves as promoting accessibility, environmental awareness, and community well-being while mitigating ethical risks in privacy and ownership. These two design explorations allow us to imagine early AI applications for sound with their opportunities and limitations. It is our intention that SoundAI responds to the real needs of individuals, natural habitats, and other species to make a positive societal and environmental impact.

Sounds can evoke various emotional reactions based not only on their acoustic properties but also on their perceived meanings. Hyperacusis is a condition in which individuals experience heightened sensitivity to everyday sounds, often resulting in anxiety, fear, and avoidance behaviors. The concept of soundscape—an individual’s subjective experience of the acoustic environment, combined with the appraisal theory provides insights for understanding the emotional roots of these behaviors. To support behavioral transformation, persuasive gamification offers a promising approach for designing effective and engaging interventions. By incorporating soundscapes into game world, such interventions can help individuals gradually acclimate to distressing sounds in a controlled and interactive way. This study aims to develop a design guideline for persuasive gamified interventions targeting hyperacusis listeners. We first integrated insights from literature and map hyperacusis behavior patterns based on appraisal processes. Semi-structured interviews with seven domain experts then inform six key design considerations: understanding hyperacusis listeners, entry points into the game world, the use of soundscapes as game elements, in-game coping strategies, the transfer effect to real-world behaviors, and ethical concerns.

Soundscape is a recent notion, complementary to environmental noise control. It regards the total auditory experience of the acoustic environment based on descriptors ranging from pleasant to annoying, and from eventful to uneventful. This approach is used outdoors, but indoors too, for example in offices and hospitals. In Intensive Care Units (ICUs) many specific dominant sounds are prevalent; not only permanently active medical equipment such as ventilators, dialysis machines, but also alarms, and conversations by staff members. In such cases a special instance of the soundscape tool is required. The current work focuses on the processing and analysis of 24h long acoustic sets of sound data, collected continuously in the Adult ICU at Erasmus Medical Center. In addition to standard noise metrics like equivalent, peak sound levels and statistical indices, this research explores alternative measures such as restorative periods, fast rises, traffic noise index (TNI) and more metrics based on distributional variables. By adapting metrics from the realm of environmental noise to the ICU context, this work aims to provide a more comprehensive characterization of the acoustic environment. These insights will also facilitate relationships with qualitative soundscape descriptors to be collected in later stages of the project.

This paper addresses the integration of sound into product design and engineering. Recognizing a gap in design education, the study focuses on introducing product design and engineering students to the principles of product sound design (PSD). By means of interviews with experts and literature research, a three-level framework is developed, addressing product features, object composition, and environmental context. This framework can assist students in understanding how engineering decisions influence sound perception at the product level, how material and structural choices affect sound at the object level, and how environmental factors shape the overall auditory experience. The framework served as the foundation for conceptualizing Les Sons, an educational software tool that mirrors these levels in its architecture. Les Sons supports students in exploring and modifying product acoustics through component and material selection. The paper stresses the role of tools like Les Sons for product sound design education, in order to practice and enhance collaboration and shared understanding in multidisciplinary contexts.

Alarm fatigue describes the desensitization, reduced alarm response, and negative emotions experienced by ICU nurses due to the excessive number of alarms generated by patient monitoring systems. Although alarms are intended to prompt action, high numbers of non-actionable alarms undermine nurse responsiveness and pose risks to patient safety. This study builds on previous research of the authors exploring the characteristics of ICU nurses as users of the system, system features of patient monitors, and alarm load across different ICU types. In this study, we synthesized previous findings into research insights. We conducted a multi-disciplinary workshop using a sound-driven design approach with diverse stakeholders, including ICU nurses, doctors, industry experts, designers, and researchers. Previous research insights were used to stimulate discussion and develop design directions aimed at mitigating alarm fatigue and supporting ICU nurse needs. The outcomes of this workshop produced actionable solution bundles that consolidate previous insights and introduce novel approaches, offering a holistic and collaborative perspective to mitigating alarm fatigue.

In Intensive Care Units (ICUs), excessive non-human and human sounds cause behavioural and psychological problems in patients and reduce professionals' job satisfaction and performance. Rather than relying solely on quantitative (psycho/acoustic) metrics, their combination with qualitative data (soundscape descriptors) provides the most reliable method to assess this context, as it considers the perceived environment. Moreover, sound event detection (SED) and classification techniques enhance the reliability of the assessment model. However, they also raise ethical concerns regarding vulnerable patients' rights. Therefore, the development of audio data ethics is essential for designing research strategies that strike a balance between patients' rights and research effectiveness. This study aims to define audio data ethics based on expert interviews and outline the basics of a tool to identify and assess risks for mitigation strategies. Results indicate that quantitative and qualitative data present minimal ethical risks, but audio recording for event identification poses significant ones. Managing these risks helps prevent patient re-identification, discrimination, and mistrust in research. The results will be validated in an ICU.

Intensive care nurses are regularly exposed to loud sounds, but it is crucial to understand which sounds they consciously perceive during their shifts. This study, conducted in the Adult ICU at Erasmus Medical Center in the Netherlands, used a mixed-method approach to explore nurses’ auditory experiences. Over three weeks, the researchers continuously measured sound levels in patient rooms, nurse stations, and a corridor, focusing on morning shifts. Additionally, a context mapping study was conducted, by which nurses documented sound sources using portable audio recorders, arranged them on a timeline, and provided interpretations in semi-structured interviews. The findings indicate that nurses primarily hear environmental sounds and are particularly sensitive to alarm sounds during transitions. Their interpretation of ICU sounds varies based on their tasks, with both positive and negative appraisals. This suggests that ICU environments can be optimized by organizing sound events to better align with nurses’ clinical needs. Understanding the sounds nurses consciously notice and react to can help improve working conditions and patient care. By refining acoustic environments, hospitals can reduce unnecessary noise while ensuring that critical alarms remain effective, ultimately supporting both staff efficiency and patient well-being in intensive care settings.

Sound-driven design has roots in the history of Critical Alarms Lab (TU Delft) and emerged as a response to designers' need to tackle complex societal problems that cannot be solved by designing sounds only. In previous research, we discovered four different design approaches (designing THE, WITH, AGAINST sound FOR) and their corresponding problem (sonic, experiential, technical, and cultural) and solution (creative, integrative, mitigative, and purposeful) spaces. As such, we developed the ecologically-relevant TWAF framework to further understand the underlying mechanisms of sound-driven design. In this paper, we use the framework to demonstrate how different approaches are needed to holistically address complex issues when sound poses a societal threat or an opportunity for design especially in the healthcare context to improve the quality of the acoustic environment and listener experiences. With the case study in sound-driven design for healthcare, we demonstrated that sound-driven design shifts sound from being a by-product of the environment to an intentional, meaningful, and integrated experience enhancing well-being, sonic culture and quality of life.

We explored the underpinnings of providing positive listener experiences for intensive care unit (ICU) patients with compositions of added sounds. Our objective was to derive an approach to such interventions based on soundscape perception and need fulfillment. In one study, we gathered qualitative empirical data about imagined soundscapes where nine fundamental needs were fulfilled. Hierarchical clustering and thematic analysis showed that imagined soundscapes clustered into four types of sonic ambiances, i.e., affective connotations with soundscapes: Comfortable, Pleasurable, Motivating, or Stimulating ambiances. We derived four design parameters to achieve these ambiances with sound compositions: eventfulness, sonic ambiance qualities, narrative structure, and sound distribution. A sound artist was asked to use these parameters to create sound compositions. In a listening experiment, we examined their effects on the perceived pleasantness and eventfulness of soundscapes and on listeners' experienced pleasure and arousal. Soundscapes were perceived as pleasant with varying eventfulness in line with our structured approach. We found a strong correlation between pleasantness and with listener's pleasure and a moderate correlation between eventfulness and with listener's arousal. Finally, we suggested that in future research, three sonic ambiance types should be considered rather than four. Concluding, we showed that our need-driven approach could form a promising way to support ICU patients.

Intensive Care Unit (ICU) nurses are burdened by excessive number of false and irrelevant alarms generated by patient monitoring systems. Nurses rely on these patient monitoring systems for timely and relevant medical information concerning patients. However, the systems currently in place are not sensitive to the perceptual and cognitive abilities of nurses and thus fail to communicate information efficiently. An efficient communication and an effective collaboration between patient monitoring systems and ICU nurses is only possible by designing systems sensitive to the abilities and preferences of nurses. In order to design these sensitive systems, we need to gain in-depth understanding of the user group through revealing their latent individual characteristics. To this end, we conducted a survey on individual characteristics involving nurses from two IC units. Our results shed light on the personality and other characteristics of ICU nurses. Subsequently, we performed hierarchical cluster analysis to develop data-driven nurse profiles. We suggest design recommendations tailored to four distinct user profiles to address their unique needs. By optimizing the system interactions to match the natural tendencies of nurses, we aspire to alleviate the cognitive burden induced by system use to ensure that healthcare providers receive relevant information, ultimately improving patient safety.

The sound-driven design approach foregrounds the human-centred sonic, experiential and cultural aspects of listening. However, addressing the temporal and context-dependent nature of sound in multi-stakeholder, collaborative design projects is a challenging activity. Ideation methods are used to generate solutions to a design problem. During idea generation, participants use their creative cognition to generate ideas in quantity, quality, variety, and originality. If this collaboration is managed effectively, a group outperforms its members. We present Soundstorm, a collaborative card game to sensitise group-work in sound-driven generative design sessions. A pilot evaluation using a protocol study with 18 participants showed the potential of Soundstorm in facilitating iteration among team members. The study highlights the importance of putting effort and attention into preparing participants for productive generative sessions.

Intensive care units (ICUs) are the ultimate socio-technological environments known for their loud sound levels. Alarms, noise produced by patient support devices, loud conversations, physical interactions with tools and the environment in general contribute collectively to a sound quality generally perceived as low. This paper reports the results from a study conducted inside the old and new ICUs at Erasmus Medical Center, Rotterdam, the Netherlands. Sound level measurements have been collected continuously for three weeks in several matching rooms inside the old and new ICUs at full operational level at a one-year distance from one another. The results support the idea that changes in architectural layout, procedures, and culture have contributed to a significant decrease of the measured sound levels across all daily shifts, both inside patient rooms and in the nurse stations. We further discuss the results in light of a series of contextual considerations that emerged from interviews with healthcare providers (i.e., nurses and intensivists) who actively worked in both the old and the new ICU.

The hospital soundscape is known for high noise levels and a perception of chaos, leading to concerns about its impact on patients, families, professionals, and other hospital staff. This study investigates the relationship between sound, Annoyance, and sleep quality in a multi-patient neurology ward. A mixed-methods approach was employed. Interviews were conducted with medical staff (n = 7) to understand their experiences with sound. Questionnaires and sleep tracking devices (n = 20) assessed patient sleep quality and Annoyance caused by sound events. In addition, listeners (n = 28) annotated 429 nighttime audio recordings to identify sound sources and rate Annoyance level, which we considered the key emotional descriptor for patients. Over 9,200 sound events were analysed. While snoring, a patient-generated sound dominated the nighttime soundscape and was highly rated for Annoyance, and staff-generated sounds such as speech and footsteps were found to contribute more to accumulated Annoyance due to their extended duration. This study suggests that patient sleep quality can be improved by focusing on design interventions that reduce the impact of specific sounds. These might include raising awareness among staff about activities that might produce annoying sounds and implementing strategies to mitigate their disruptive effects.

Exterior vehicle sounds have been introduced in electric vehicles and as external human–machine interfaces for automated vehicles. While previous research has studied the effect of exterior vehicle sounds on detectability and acceptance, the present study takes on a different approach by examining the efficacy of such sounds in deterring people from crossing the road. An online study was conducted in which 226 participants were presented with different types of synthetic sounds, including sounds of a combustion engine, pure tones, combined tones, and beeps. Participants were presented with a scenario where a vehicle moved in a straight trajectory at a constant velocity of 30 km/h, without any accompanying visual information. Participants, acting as pedestrians, were asked to hold down a key when they felt safe to cross. After each trial, they assessed whether the vehicle sound was easy to notice, whether it gave enough information to realize that a vehicle was approaching, and whether the sound was annoying. The results showed that sounds of higher modeled perceived loudness, such as continuous tones with high frequency, were the most effective in deterring participants from crossing the road. The tested intermittent beeps resulted in lower crossing deterrence than continuous tones, presumably because no valuable information could be derived during the inter-pulse intervals. Tire noise proved to be effective in deterring participants from crossing while being the least annoying among the sounds tested. These results may prove insightful for the improvement of synthetic exterior vehicle sounds.

There is an increased awareness of how the quality of the acoustic environment impacts the lives of human beings. Several studies have shown that sound pollution has adverse effects on many populations, from infants to adults, in different environments and workplaces. Hospitals are susceptible environments that require special attention since sound can aggravate patients' health issues and negatively impact the performance of healthcare professionals. This paper focuses on Neonatal Intensive Care Units (NICU) as an especially sensitive case representing a hostile acoustic environment in which healthcare professionals have little awareness of how unwanted sounds impact the perceived quality of the soundscape. We performed a semi-systematic review of scientific literature on sound assessment studies in NICU from 2001. A thematic analysis was performed to identify emerging themes that informed the analysis of 27 technological solutions for the assessment of sound quality in indoor and outdoor environments. Solutions were categorized by functions and evaluation methods and grouped according to the characteristics of the design components, i.e., acquisition, computation, and communication strategies. Results highlight a lack of solutions to assess the qualitative characteristics of indoor environments such as NICU and forecast the footprint that different sound sources have on the indoor soundscape. Such solutions are urgently needed to empower healthcare professionals, and especially nurses, to actively modify and prevent the negative impact of unwanted sounds on NICU and critical care soundscape.

Psychological needs of users as a basis for design are at the core of design practice, yet the importance of fundamental human needs when designing soundscapes has not been studied specifically. This paper investigates the relationship between nine fundamental human needs and the affective qualities and categories of soundscapes. In a free-labeling survey study, we collected descriptions of imagined sound environments for the fulfilment of the needs, as well as ratings of the perceived affective quality of these environments. We found that needs were associated with pleasant soundscapes, while their eventfulness varied. ‘Human’ sounds were a common category for each of the nine needs considered in this study, but systematic variations of the categories were found dependent on the need. Results suggest that designing categorically different soundscapes dependent on the users’ needs will have beneficial effects.