Design Input 1
| Requirement | Justification |
| Device must be transportable | a) Maximum weight of device is 16 kg b) Device does not exceed dimensions of 109 cm length, 65.5 cm width, and 76 cm height |
| Justification | |
| a) Suggested carrying weight at waist level for women is 16 kg [1]. Women typically can carry less than men so by using the lower weight suggestion a greater portion of the population is included b) Dimensions of device are within average door size of target region [2] and comparable to transportable infant incubators in the US [3] |
|
Design Input 2
| Requirement | Justification |
| Device must support infant weight | Device chamber must support up to 7 lbs |
| Justification | |
| Device has to be able to support the weight of the infant developing inside the incubator without compromising structural integrity and risking user safety. Weight of a premature infant is between 1 - 5lbs and the average weight of a full-term infant is 7lbs [4] | |
Design Input 3
| Requirement | Specification |
| Device must maintain appropriate temperature range | Maintain internal chamber temperature between 36.5°C - 37.5°C |
| Justification | |
| Deviating outside this range may result in hypothermia or fever for the infant user | |
Design Input 4
| Requirement | Specification |
| Device must maintain appropriate humidity | Maintain relative humidity between 60% - 70% |
| Justification | |
| Humidity range specified has been identified appropriate to protect infant skin, maintain body temperature, and prevent water loss [5] | |
Design Input 5
| Requirement | Specification |
| Device must measure/sense incubator internal conditions | a) Sense temperature to ± 0.5°C b) Sense humidity to ± 1% c) Sense battery current charge to ± 1% |
| Justification | |
| Has to ensure that device will be able to provide an accurate measure for the internal conditions that will be showcased to the caregiver | |
Design Input 6
| Requirement | Specification |
| Device must have an audible and visual display/alert system for internal conditions | a) Display parameter and value in plain text b) Red, yellow, and green LED status indicators c) Audible pattern for medium priority (intermittent) and high priority (sustained) alerts |
| Justification | |
| b) Red, yellow, green indicators are commonly understood visual status markers [6] that will draw caregiver attention to display where further details of system intervention needs will allow caregiver to intervene as necessary c) Audible pattern will adhere to internationally accepted sounds and patterns for medical monitoring [7] |
|
Design Input 7
| Requirement | Specification |
| Device must operate at low appropriate sound level | Sound pressure level within the chamber is < 45 dB |
| Justification | |
| American Association of Pediatrics determined > 45 dB as level of concern for newborn hearing development damage [8] |
|
Design Input 8
| Requirement | Specification |
| Device must maintain power supply necessary to operate for duration of use | a) Minimum power necessary for all components b) Minimum duration of use is 2 hrs |
| Justification | |
| Appropriate amount of current must run through each component for device to operate | |
Design Input 9
| Requirement | Specification |
| Device must filter contaminants and airflow through the | a) Minimum filter efficiency of MERV - 14 [9] b) Airflow of six changes per hour [10] - approximately 0.6 m^3/h |
| Justification | |
| a) MERV - 15 is the minimum filtration efficiency stated by NSI/ASHRAE/ASHE Standard | |
Design Input 10
| Requirement | Specification |
| Components of device must be serviceable and replaceable within a reasonable timeframe | a) Must function for at least 2 hrs continuously without intervention b) Function for up to 4 weeks before needing maintenance on system components |
| Justification | |
| a) About 71% of the total population and 72% of women able to bear children live within 2 hours travel distance from the hospital [11], incubator should be able to support infant for duration of travel to next nearest level of care b) Cargo may be backlogged for up to three week, unable to be delivered[12], serviceable parts should sustain until new parts are able to be delivered |
|
[1]What is the maximum weight limit I can lift at work? (n.d.). From https://www.beckettandco.co.uk/manual-handling-faq-weight/ [2]What are the standard door sizes in your country? (2018, October 18). From https://www.doorsdirect.co.za/what-are-the-standard-door-sizes-in-your-country [3]Equipment for the way you operate [Https://storage.googleapis.com/avante/documents/dre_neoglider.pdf]. (n.d.). Louisville: DRE NeoGLIDER. [4]Caring for a premature baby: What parents need to know. (2019, October 31). Retrieved from https://www.healthychildren.org/English/ages-stages/baby/preemie/Pages/Caring-For-A-Premature-Baby.aspx#:~:text=Characteristics%20of%20Babies%20Born%20Premature,kg [5]Glass, L., & Valdez, A. (2021). Preterm Infant Incubator Humidity Levels: A Systematic Review. Advances in neonatal care : official journal of the National Association of Neonatal Nurses, 21(4), 297–307. https://doi.org/10.1097/ANC.0000000000000791 [6]Neonatal guidelines 2022-2024. (2022). Retrieved from https://b-ok.cc/book/23052748/5952b5 [7]Schweber, B. (2020, July 22). How to properly implement audible alarms in medical monitoring. Retrieved from https://www.digikey.com/en/articles/how-to-properly-implement-audible-alarms-in-medical-monitoring [8]Noise: A hazard for the fetus and newborn. (1997). Pediatrics, 100(4), 724-727. doi:10.1542/peds.100.4.724 [9]Ventilation of Health Care Facilities [PDF]. (2020, July 31). Atlanta: ASHRAE. [10]Neonatal guidelines 2022-2024. (2022). Retrieved from https://b-ok.cc/book/23052748/5952b5 [11]This is how far people in Africa have to travel to reach a hospital. (2018, September 26). From https://www.weforum.org/agenda/2018/09/people-across-africa-have-to-travel-far-to-get-to-a-hospital-we-worked-out-how-far [12]Raballand, G., & Oliver, J. (2013, June 26). Why does cargo sit so long in African ports? not just poor infrastructure... poor incentives. From https://blogs.worldbank.org/trade/why-does-cargo-sit-so-long-african-ports-not-just-poor-infrastructure-poor-incentives