American National Standards Institute Research Articles

Ultralow energy photoacoustic microscopy for ocular imaging in vivo.

.Significance: The development of ultralow energy photoacoustic microscopy (PAM) on the clinically relevant pigmented rabbit eye model paves a road toward translation of the emerging PAM technology in ophthalmology clinics.Aim: Since the eye is particularly vulnerable to laser damage, we aim to develop an ultralow energy PAM system to significantly improve the laser safety of PAM by increasing the sensitivity of the system and reducing the incident laser energy for imaging.Approach: A multichannel data acquisition circuit with two-stage signal amplification was specially designed, which, in combination with the application of 3 by 3 median filter in the spatial domain, significantly improved the signal-to-noise ratio of the PAM system. The safety of this system was validated by histopathology, fluorescein angiography, and fundus photography.Results: Experiments performed on pigmented rabbits demonstrated that, when using this ultralow energy PAM system, satisfactory image quality can be achieved in the eye with an incident laser fluence that is only 1% of the American National Standards Institute safety limit. Fundus photography, fluorescein angiography, and histopathology were performed after the imaging procedure, and no retinal or ocular damage was observed.Conclusions: The proposed ultralow energy PAM system has excellent safety and holds potential to be developed into a clinical tool for ocular imaging.

ANSI/ASSP Z9.14-2020 Testing and Performance-Verification Methodologies for Biosafety Level 3 (BSL-3) and Animal Biosafety Level 3 (ABSL-3) Ventilation Systems.

The American National Standards Institute has approved the revised standard ANSI/ASSP Z9.14-2020, "Testing and Performance-Verification Methodologies for Biosafety Level 3 (BSL-3) and Animal Biosafety Level 3 (ABSL-3) Ventilation Systems"; the revision was published on March 31, 2020. ANSI/ASSP Z9.14-2020 focuses on performance verification of engineering controls related specifically to ventilation system features of BSL-3/ABSL-3 facilities. The revised standard has been enhanced to include new definitions; new guidance for developing corrective action plans and performing verification of conformance to regulations, appendices, risk assessment matrices, and checklists dedicated to performing a facility risk assessment; and numerous updates to the original content.

What Does Language Have to Do With It? The Impact of Age and Bilingual Experience on Inhibitory Control in an Auditory Dichotic Listening Task.

Purpose The purpose of the current study was to examine inhibition of irrelevant information in younger and older English monolingual and Spanish-English bilingual adults. Method Sixty-one participants divided into four groups: 15 younger English monolinguals, 16 younger Spanish-English bilinguals, 15 older English monolinguals, and 15 older Spanish-English bilinguals participated in this study. Younger participants were 18-25 years of age, and older participants were 47-62 years of age. Bilingual participants had learned Spanish from birth and began learning English by the age of 3 years old (SD = 3.1). All participants had hearing thresholds of < 25 dB HL from 250 to 4000 Hz, bilaterally (American National Standards Institute [ANSI], 2004) and were right-handed. Inhibition was measured using a forced-attention dichotic consonant vowel listening task with a prime stimulus and the Simon task, a nonverbal visual test. Results Younger participants were better able to inhibit the irrelevant auditory and visual stimuli and modulate their attention according to the instructions that they were given compared to the older participants. However, no significant differences in inhibition performance or attention modulation were evidenced between the monolingual and bilingual groups in any of the dichotic listening conditions or on the Simon task. Conclusions No significant differences in performance on an auditory or a visual test of inhibition of irrelevant information was evidenced between the monolingual and bilingual participants in this study. These findings suggest that younger and older adult, early balanced Spanish-English bilinguals may not exhibit an advantage in the inhibition of irrelevant information compared to younger and older adult English monolinguals.

Comparing the performance of ultralight folding manual wheelchairs using standardized tests

Objective To evaluate ultralight folding manual wheelchairs (UFMWs) in order to produce comparative data on their strength, durability, stability and cost–benefit, and to determine progress of wheelchairs by comparing these results to results of past studies. Design Engineering testing using American National Standards Institute (ANSI) and Rehabilitation Engineering and Assistive Technology Society of North America (RESNA) standards. Setting Laboratory testing of UFMW stability, and static, impact and fatigue strength performance with three devices using ANSI/RESNA standardized tests. Participants The three wheelchair models were the TiLite Aero X (Permobil, Lebanon, TN), Sunrise Medical Quickie 2 (Fresno, CA) and Ki Mobility Catalyst 5 (Stevens Point, WI). Interventions ANSI/RESNA standardized tests. Main outcome measures Mass and critical measurements, static stability, static strength, impact strength, fatigue strength and cost analysis. Results The ultralight folding wheelchairs continued to outperform their lightweight and rigid framed counterparts. According to these data, the quality of ultralight wheelchairs has not declined over the past 10 years. The Ki Catalyst did not pass strength and durability testing, while the TiLite Aero X and Sunrise Medical Quickie 2 surpassed these tests. Conclusions This result exemplifies the need for ongoing research to identify whether wheelchairs satisfy ANSI/RESNA testing requirements and highlights the importance of creating a resource data set. This is particularly important when numerous other wheelchairs fail to meet minimum ANSI/RESNA requirements. Implications for Rehabilitation Folding frame wheelchairs offer benefits such as transportability and convenience that may benefit certain wheelchair users, assuming their durability is sufficient and they provide similar benefits vs. other wheelchair construction. Previous studies have shown that folding wheelchairs perform meet the minimum requirements of standardized testing, and it is important to see if durability has increased, decreased or remained the same over the years. Other wheelchair types have remained stagnant with respect to durability and are less likely to meet the minimum durability requirements. Durable devices will improve a wheelchair user’s quality of life by reducing downtime while waiting for repairs, and also reduce the likelihood of injury due to component failure.

Book Reviews

Presents a review of the book, "The Cambridge Handbook of Technical Standardization Law: Further Intersect ions of Public and Private Law (Contreras, J.L., Ed.). This book on technical standardization law is one of the more timely books available in this area. It in fact a continuation of the previous book by the same editor covering technical standardization law from the perspective of competition, antitrust, and patents. However, in this volume 2 of the book, the focus is on the intersections of public and private laws with respect to standardization. It surveys how today’s standardization is affected by both the public and private laws across the United States and Europe. This book is useful for researchers, practitioners, post-graduate students, lawyers, judges, policy makers, and most importantly to all those who are involved in communication standardization activities in any capacity. The main feature of this book is that it gives examples of standards that are currently in practice. For instance, throughout the book, the discussion revolves around standardization bodies such as the European Telecommunications Standards Institute (ETSI), the American National Standard Institute (ANSI), the International Standards Organization (ISO), the Internet Engineering Task Force (IETF), the British Standards Institute (BSI), and the International Telecommunications Union (ITU). Additionally, this book covers copyright and trademark issues with respect to communication protocols, standards, and technologies such as HTML, XML, HTTP, Bluetooth, Wi-Fi, and USB. On top of this discussion, one of the unique features of this book is its coverage of open standards and government policies for their adoption, both in the United- States and Europe. Overall, however, this book is a good reference book for courses on telecom policy, cyber ethics and laws, and standardization laws. In simple words, it is important to investigate how international trade law, copyright, trademarks, certifications, and legal frameworks influence private standardization activities, more particularly in the context of the networked economy and broadly in the communications sector.

A Review of United States Arboricultural Operation Fatal and Nonfatal Incidents (2001–2017): Implications for Safety Training

The objective of this study was to identify and quantify the hazards present during arboricultural operations. The Occupational Safety and Health Administration Fatality and Catastrophe incident database and other Bureau of Labor Statistic sources were analyzed for arboricultural operation incidents within the 17-year period from 2001 through 2017. There were 865 fatal and 441 nonfatal incidents reviewed from this period. The leading four fatal incidents, from the largest to the smallest number of fatalities, were climber falls, workers struck by a falling tree, workers making indirect contact with an electric current, and workers struck by a falling branch. Climber falls were also the leading incident for severe nonfatal injuries, followed by ground workers struck by a falling branch, workers struck by a chain saw, and falls by aerial device operators. The American National Standards Institute Z133 American National Standard for Arboricultural Operations—Safety Requirements establishes safety requirements and recommendations for arboricultural operations in the United States. It addresses common hazard sources and has guidelines to avoid, eliminate, or reduce them. Safety training programs should emphasize the most common hazard sources for fatal and nonfatal incidents and follow the ANSI Z.

All‐Fluorescence White Organic Light‐Emitting Diodes Exceeding 20% EQEs by Rational Manipulation of Singlet and Triplet Excitons

AbstractWhite organic light‐emitting diodes (WOLEDs) composed of conventional fluorophores possess color purity, low efficiency roll‐off, and rare metal absence, but suffer from theoretical limits due to the lack of triplet utilization. Due to the different diffusion distance for singlets and triplets, multiple Förster resonance energy transfer (FRET) channels can be adequately built up. Herein, besides the complementary component, a blue fluorescence layer, hosted by pure hydrocarbon material SF4‐TPE, is put forward as the spatial exciton manipulating layer to rationally allocate singlets and triplets to the corresponding channels. Hence, singlets are captured by the blue fluorophore, diffused triplets subsequently undergo energy resonance between the blue fluorophore and green assistant, and up‐conversion effect for eventual emission from the yellow fluorophore. Owing to the utilization of singlets and triplets, all‐fluorescence WOLEDs exhibit high efficiency exceeding 20%, with slight efficiency roll‐off even under high luminance of 5000 cd cm−2. Moreover, CIE coordinates can be surrounding and precisely inside the American National Standard Institute (ANSI) quadrangles, as well as outstanding color stability (ΔCIE‐(x, y) within (0.001, 0.012)) from 300 to 13000 cd cm−2.

Design a three-phase step-down power supply based on ANSI/IEEE standard

An alternating current three-phase step-down power supply design is a system development process that creates an existing three-phase system whereby the primary side of the Y relationship and the secondary side of the Y relationship. The problems in the design of three-phase step-down power supply circuit are the existence of harmonics, losses and unbalance voltage. The power supply test is carried out using no-load and linear load resistance with the value of resistances in range of hundreds ohm. The circuit is tested for resistance number one, resistance number two, resistance number three and resistance number four transformers to obtain a power supply design that meet American National Standards Institute or Institute of Electrical and Electronic Engineering standards. The test results of four transformers in the form of three-phase step-down found that resistance number one and resistance number two type transformers have the lowest copper loss percentage, core loss, voltage THD and low unbalance voltage, so that these power supply can be made according to ANSI/IEEE provisions.

94: Noninvasive instantaneous measurement of neonatal brain oxygenation with light emitting diodes to detect hypoxic-ischemic encephalopathy

We currently use electronic fetal heart rate monitoring as a screening test for fetal hypoxic-ischemic encephalopathy (HIE), and neonates suspected of having HIE at birth are triaged to hypothermia treatment within 6 hours of birth. We have demonstrated the transcranial, instantaneous measurement of superior sagittal sinus oxygen saturation (sO2) in an in vivo neonatal piglet model to detect HIE using functional photoacoustic (fPA) imaging with pulsed laser light generated by a Nd:YAG optical parametric oscillator. Convenience and safety will be improved if brain oxygenation can be measured with a small, inexpensive, light emitting diode (LED) as the light source. Neonatal piglets, aged 3-7-days, were placed under general endotracheal anesthesia with a catheter in the superior sagittal sinus (n=5). Systemic hypoxia was produced by stepwise decreasing fractionally inspired oxygen (FiO2): 100, 21, 19, 17, 15, 14, 13, 12, 11, 10%. At each FiO2, the LED-based fPA imaging system captured a coronal cross-section of the piglet head,(Fig 1a) followed by direct blood sampling. Near-infrared LEDs emitted pulsed light at 690 and 850 nm at 50- to 125-times lower energy level compared to that emitted by the Nd:YAG laser (0.18-0.4mJ vs. 10mJ per pulse). We used an energy density of 0.02-0.05mJ/cm2, well below the American National Standards Institute safety limit in human tissue of 20mJ/cm2. We compared the fPA measurement of superior sagittal sinus sO2 against that measured directly by blood sampling. fPA measurements correlated with direct measurements of sO2 with R2 = 0.68.(Fig 1b) The correlation between the slope (0.94) and y-intercept (4.14%) were very close to ideal positive correlation. The detection precision in the critical sagittal sinus sO2 (< 30%) was confirmed with sensitivity (94.12%), specificity (85.71%), accuracy (89.47%), positive predictive value (84.21%), and negative predictive value (94.74%). LEDs can instantaneously and noninvasively measure superior sagittal sinus sO2 which suggests the feasibility of fetal and neonatal brain monitoring to detect HIE.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Nonlinear Optical Corneal Crosslinking, Mechanical Stiffening, and Corneal Flattening Using Amplified Femtosecond Pulses.

PurposeWe have shown that nonlinear optical corneal crosslinking (NLO CXL) and stiffening can be achieved in ex vivo rabbit corneas using an 80-MHz, 760-nm femtosecond (FS) laser, however the required power was beyond the American National Standard Institute limit. The purpose of this study was to test the efficacy of amplified FS pulses to perform CXL to reduce power by increasing pulse energy.MethodsA variable numerical aperture laser scanning delivery system was coupled to a 1030-nm laser with a noncollinear optical parametric amplifier to generate 760 nm, 50 to 150 kHz amplified FS pulses with 79.5-μm axial and 2.9-μm lateral two-photon focal volume. Ex vivo rabbit corneas received NLO CXL, and effectiveness was assessed by measuring collagen autofluorescence (CAF) and mechanical stiffening. NLO CXL was also performed in 14 live rabbits, and changes in corneal topography were measured using an Orbscan.ResultsAmplified pulses (0.3 μJ) generated significant CAF that increased logarithmically with decreasing scan speed; achieving equivalent CAF to UVA CXL at 15.5 mm/s. Indentation testing detected a 62% increase in stiffness compared to control, and corneal topography measurements revealed a significant decrease of 1.0 ± 0.8 diopter by 1 month (P < 0.05).ConclusionsThese results show that NLO CXL using amplified pulses can produce corneal collagen CXL comparable to UVA CXL.Translational RelevanceNLO CXL using amplified pulses can produce corneal CXL comparable to UVA CXL, suggesting a potential clinical application in which NLO CXL can be used to perform personalized crosslinking for treatment of refractive errors and keratoconus.

Effect of correlated colour temperature and illuminance levels on user’s visual perception under LED lighting in Taiwan

This study aimed to utilise the characteristics of light-emitting diode (LED) lighting, including the adjustable correlated colour temperature (CCT) and illuminance levels, to evaluate the effects of various CCT and illuminance level combinations on visual perception and their patterns under different lighting conditions. Five white light balances with different CCTs were created together with four levels of illuminance. Based on the patterns of visual perception, when the CCT increased with the illuminance levels, the participants’ visual perception changed from dim, boring, and sleepy to intense, vivid, energetic, and bright. As the CCT decreased, the participants gradually perceived the lighting as warm and relaxing. As illuminance levels increased, dim and unpleasant feelings progressively changed to bright and pleasant ones. The study attempted to identify lighting combinations that can respond to different psychological needs and can be used as a guide in the future design of lighting equipment. Practitioner summary: Appropriate lighting conditions could aid individuals in increasing the quality of life. This study conducted an experiment to evaluate the effects of various correlated colour temperature and illuminance level combinations on visual perception by using LED lighting. The results showed the effect of the different lighting combinations on the visual perception of the participants. Abbreviation: LED: light-emitting diode; CCT: correlated colour temperature; K: Kelvin; lx: Lux; CIE: Commission Internationale de l’Eclairage; ANSI: American National Standards Institute

Performance evaluation of a natural based adhesive derived from Irvingia wood species kernel extracts on wood panel production

Irvingia seed kernels have been identified as potential raw materials for a wide range of applications such as biodiesel, cosmetics, perfume, and soap. As a result, the Irvingia wood species is earmarked for domestication globally in order to commercially exploit these potential benefits. This study investigated the physical and mechanical properties of experimental panels made with pine (Pinus elliottii) wood particles, using modified Irvingia gabonensis (IG) and Irvingia wombolu (IW) extracts as a binder. The mean values of modulus of rupture (MOR) and modulus of elasticity (MOE) for the panels produced with this Irvingia-based adhesive were 5.8 and 1251 MPa, respectively. These values are within the minimum requirement for MOR and MOE (5.5 and 1034 MPa, respectively) for panel grade 1-L-1 as specified by the American National Standards Institute A208.1. The results from the study show that Irvingia kernel extracts may be considered as a potential environmentally friendly adhesive for wood composite manufacture.

Use of an Application to Verify Classroom Acoustic Recommendations for Children Who Are Hard of Hearing in a General Education Setting.

Purpose Classrooms including children who are hard of hearing (CHH) may be modified to manage noise and reverberation and improve speech perception. Little is known about the acoustic characteristics of contemporary general education classrooms that include CHH compared to classrooms of typical peers. We proposed the following research questions about the acoustic environment of general education classrooms including CHH: (a) How reliable are acoustic measurements collected using an iOS device, application, and external microphone? (b) What proportion of classrooms meet the American National Standards Institute's standards for unoccupied noise levels and reverberation? Method A smartphone application was used to measure sound levels, reverberation, and clarity for 164 general education classrooms including CHH. Linear mixed models were used to examine the following: (a) reliability of acoustic measures made using an application and external microphone and (b) predictors of sound levels, reverberation, and clarity for elementary classrooms including CHH. Results Results indicate the application reliably measures classroom acoustics. Classrooms exceeded the American National Standards Institute's recommended noise levels, but met reverberation time guidelines. Grade; heating, ventilation, and air conditioning status; and room volume predicted classroom acoustics. Conclusions As a screening tool, the application was shown to be effective in reliably measuring reverberation and classroom noise levels. The high levels of noise in unoccupied classrooms indicate a need for increased use of noise abatement strategies and the use of remote-microphone systems, especially in classrooms where noise levels cannot feasibly be reduced. Using an application may be a cost-effective method for monitoring important acoustic features that impact children's ability to understand speech in the classroom.

Innovation Drives Iron Pipe Joint Technology

The United States recently celebrated its centennial year of standards for engineering products. Today's American National Standards Institute (ANSI) dates to 1918, and in collaboration with AWWA, it and other organizations produced a standard for iron pipe in 1926. This and other standards for products and processes are major reasons North America has the finest municipal water systems in the world.

Stepwise shock compression of aluminum at room and elevated temperatures

With the aim of expanding the measurable range of high-rate deformation, experiments were conducted in which AD1 aluminum [A199.3 under the international classification and AA1135 in the USA (American National Standards Institute)] was subjected to stepwise shock compression at both room temperature and in the range of 498–530 °C. Measurements of the width of the plastic shock waves revealed that the anomalous thermal hardening at strain rates exceeding 105 s−1 is maintained upon increasing the deformation up to at least 6.5%. The hysteresis during shock compression and unloading cycles of the elastic–plastic body was analyzed. The results indicated that determination of the stress states behind the plastic shock wave utilizing this method requires higher than usual measurements and calculation accuracies.

High-resolution multimodal photoacoustic microscopy and optical coherence tomography image-guided laser induced branch retinal vein occlusion in living rabbits

Joint high-resolution multimodal photoacoustic microscopy (PAM) and optical coherence tomography (OCT) was developed to improve the efficiency for visualizing newly developed retinal neovascularization (RNV) and to monitor the dynamic changes of retinal vein occlusion (RVO) in living rabbits. The RNV and RVO models were created in New Zealand rabbits by Rose Bengal laser-induced RVO. Dual modalities imaging equipment, including color fundus photography, fluorescein angiography (FA), OCT, and PAM, was used to image and assess the changes of retinal vasculature. In vivo experimental results exhibited that not only the treatment boundaries and the position of the occluded vasculature but also the structure of individual RNV were markedly observed using PAM platform with great resolution and high image contrast. The laser light energy of 80 nJ was used to induce photoacoustic signal, which is approximately half the energy of the American National Standards Institute safety limit. A cross-sectional structure of RNV was identified with the OCT modality. Furthermore, vibrant transformations in the RNV and the retinal morphology were examined at different times after laser occlusion: days 4, 28, 35, 49, and 90. PAM revealed high contrast and high resolution vascular imaging of the retina and choroid with amplified penetration depth. Through the present custom-built imaging system, both RNV and RVO can be reconstructed and observed in two and three dimensions. A unique dual modality A unique dual modality PAM and OCT can help precisely visualize and distinguish individual microvessels, microvessel depth, and the surrounding anatomy. Thus, the proposed multimodal ocular imaging platform may offer a potential equipment to enhance classification of microvasculature in a reliable and proficient manner in larger rabbit eyes.

Invasive Validation of Antares, a New Algorithm to Calculate Central Blood Pressure from Oscillometric Upper Arm Pulse Waves.

Background: Antares is an algorithm for pulse wave analysis (PWA) by oscillometric blood pressure (BP) monitors in order to estimate central (aortic) blood pressure (cBP). Antares aims to enable brachial cuff-based BP monitors to be type II-devices, determining absolute cBP values independently of potential peripheral BP inaccuracies. The present study is an invasive validation of the Antares algorithm in the custo screen 400. Methods: We followed entirely the 2017 ARTERY protocol for validation of non-invasive cBP devices, the 2013 American National Standards Institute, Inc./Association for the Advancement of Medical Instrumentation/International Organization for Standardization (ANSI/AAMI/ISO) 81060-2 and 2018 AAMI/European Society of Hypertension (ESH)/ISO validation standard protocols. In total, 191 patients undergoing cardiac catheterization were included, of which 145 patients entered analysis. Invasive cBP recordings were compared to simultaneous non-invasive cBP estimations using the Antares algorithm, integrated into an oscillometric BP monitor. Results: Mean difference between invasive and non-invasively estimated systolic cBP was 0.71 mmHg with standard deviation of 5.95 mmHg, fulfilling highest validation criteria. Conclusion: Antares is the first algorithm for estimation of cBP that entirely fulfills the 2017 ARTERY and AAMI/ESH/ISO validation protocols. The Antares algorithm turns the custo screen 400 BP monitor into a type II-device. Integration of Antares into commercially available BP monitors could make it possible to measure PWA parameters in virtually every practice in future.

Developing an In-House Biological Safety Cabinet Certification Program at the University of North Dakota.

Biological safety cabinets (BSCs) are the primary means of containment used in laboratories worldwide. To ensure the proper functioning of BSCs, they need to be certified annually, at a minimum, per National Sanitation Foundation (NSF)/American National Standards Institute Standard 49. A common problem most organizations face is that in many instances, the technicians who certify the cabinets are not accredited by the NSF. Additionally, in states or regions that do not have local NSF accredited field certifiers, it takes weeks to get a service request completed, thereby delaying the research work of the laboratory. Moreover, in such instances, the cost associated with cabinet certification and repair can be very high. This led the Office of Safety at the University of North Dakota to do a thorough cost-benefit analysis of developing an in-house BSC certification program. After completing the training and testing requirements for the NSF's advanced accreditation program, the BSC certification program was initiated on campus. The identified benefits led to the initiation of a program in both local and regional capacity for repair, maintenance, and certification of BSCs, and the university's experiences were shared with other universities. By developing an in-house BSC certification program, the University of North Dakota was able to reduce wait times associated with service repairs, reduce costs, and generate revenue for the department. Furthermore, this led to improved hands-on training programs related to BSC use in laboratories working with biohazardous agents.

Identification of hydrogen flammability in steam generator compartment of OPR1000 using MELCOR and CFX codes

Abstract The MELCOR code useful for a plant-specific hydrogen risk analysis has inevitable limitations in prediction of a turbulent flow of a hydrogen mixture. To investigate the accuracy of the hydrogen risk analysis by the MELCOR code, results for the turbulent gas behavior at pipe rupture accident were compared with CFX results which were verified by the American National Standard Institute (ANSI) model. The postulated accident scenario was selected to be surge line failure induced by station blackout of an Optimized Power Reactor 1000 MWe (OPR1000). When the surge line failure occurred, the flow out of the surgeline was strongly turbulent, from which the MELCOR code predicted that a substantial amount of hydrogen could be released. Nevertheless, the results indicated nonflammable mixtures owing to the high steam concentration released before the failure. On the other hand, the CFX code solving the three-dimensional fluid dynamics by incorporating the turbulence closure model predicted that the flammable area continuously existed at the jet interface even in the rising hydrogen mixtures. In conclusion, this study confirmed that the MELCOR code, which has limitations in turbulence analysis, could underestimate the existence of local combustible gas at pipe rupture accident. This clear comparison between two codes can contribute to establishing a guideline for computational hydrogen risk analysis.

Wireless Coexistence Testing in the 5 GHz Band with LTE-LAA Signals.

Exploiting unlicensed spectrum bands for cellular communication is a rapidly embraced trend by industry stakeholders. Accordingly, the specifications of Long Term Evolution (LTE) were extended in Release 13 to allow unlicensed spectrum operation, also known as LTE-Licensed Assisted Access (LAA). LTE is widely adopted, and there is a potential for significant coexistence impact of LTE-LAA on users of unlicensed spectrum including wireless medical devices, whether adopters of the new technology or incumbents. Therefore, work was initiated to revise and update the American National Standards Institute (ANSI) C63.27 standard for evaluation of wireless coexistence. This paper details the experimental work conducted at the Electromagnetic Compatibility and Wireless Laboratory, U.S. Food and Drug Administration, to investigate the use of LAA signals for wireless coexistence testing. A software defined radio platform was deployed to generate realistic LAA signals and measure the wireless coexistence impact on the LAA communication link. The equipment under test (EUT) used IEEE 802.11ac as an example incumbent technology in the 5 GHz band. The standardized radiated anechoic chamber method was used for testing. Results highlight the mutual coexistence impact of LAA in the 5 GHz band and suggest that selecting an LAA signal with the maximum possible channel time occupancy and the highest possible modulation and coding scheme (MCS) yields the most impactful coexistence situation on both the EUT and the LAA system.