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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 865 records · Page 48
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Comprehensive Performance Calibration Guidance for Perovskites and Other Emerging Solar Cells

Emerging photovoltaic (PV) technologies (e.g., organic, perovskite, and solution processed quantum dot) have attracted remarkable attention with the rapid growth of their efficiencies, and their transition toward commercialization. Accurate and reliable efficiency measurements of these PV technologies are crucial, yet much more complicated than for conventional PV technologies due to the former's pronounced dynamic responses to changes in measurement conditions (e.g., current–voltage (I–V) scan rate and preconditioning) and their susceptibility to degradation. Adjustments to the measurement procedures are therefore necessary so that a reproducible “steady state” is reached during measurement. Furthermore, given the small size of many emerging cells, inappropriate device area definition and solar simulator setup can lead to measurement errors. Here, comprehensive efficiency calibration guidance is offered for emerging solar cells, including area measurement; spectral irradiance translation to standard test conditions; and steady-state electrical performance. The necessity of reporting steady-state efficiency is justified with a statistical performance comparison between conventional and steady-state I–V scans over hundreds of cells the group has received globally for efficiency certifications. The procedures described here do not require specialized measurement instrumentation; what matters most are changes to the measurement protocols. These described changes aim to enable better comparisons between reported efficiencies.

14 SOLAR ENERGY↗
DOE OSTI2019

Quantitative guidance for efficient vertical flow measurements at the sediment–water interface using temperature–depth profiles

Upward discharge to surface water bodies can be quantified using analytical models based on temperature–depth (T-z) profiles. The use of sediment T-z profiles is attractive as discharge estimates can be obtained using point-in-time data that are collected inexpensively and rapidly. Previous studies have identified that T-z methods can only be applied at times of the year when there is significant difference between the streambed–water interface and deeper sediment temperatures (e.g., winter and summer). However, surface water temperatures also vary diurnally, and the influence of these variations on discharge estimates from T-z methods is poorly understood. For this study, synthetic T-z profiles were generated numerically using measured streambed interface temperature data to assess the influence of diurnal temperature variations on discharge estimation and provide insight into the suitable application of T-z methods. Results show that the time of day of data collection can have a substantial influence on vertical flux estimates using T-z methods. For low groundwater discharge fluxes (e.g., 0.1 m d -1 ), daily transience in streambed temperatures led to relatively large errors in estimated flow magnitude and direction. For higher discharge fluxes (1.5 m d -1 ), the influence of transient streambed temperatures on discharge estimates was strongly reduced. Discharge estimates from point-in-time T-z profiles were most accurate when the uppermost point in the T-z profile was near the bed interface daily mean (two time periods daily). Where temperature time series data are available, daily averaged T-z profiles can produce accurate discharge estimates across a wide range of discharge rates. Seasonality in shallow groundwater temperature generally had a negligible influence on vertical flow estimates. Finally, these findings can be used to plan field campaigns and provide guidance on the optimal application of T-z methods to quantify vertical groundwater discharge to surface water bodies.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

A Metric Space with LCOE Isolines for Research Guidance in wind and hydrokinetic energy systems

This paper introduces a new Metric Space to guide the design of advanced wind energy systems and hydrokinetic energy converters such as tidal, ocean current and riverine turbines. The Metric Space can analyse farms that combine different or identical turbines and stand-alone turbines. The first metric (M1) of the space considers the efficiency of the turbines in the farm, which is also proportional to the specific power per swept area at a given wind/water velocity (W/m 2 ). The second metric (M2) describes the specific rotor area per unit of mass of the turbines (m 2 /kg). Both metrics depend on the primary design characteristics of the turbines, such as swept area, system size and mass, materials and efficiency, and are independent at first from external characteristics, such as atmospheric and ocean site conditions, cost of materials and economic factors. Combining both metrics, and for a given set of external characteristics, the resulting Metric Space M2/M1 displays the Levelized Cost of Energy (LCOE) standards as isolines. This graphical representation provides a quick understanding of the cost and state of the technology. It also offers a practical guidance to choose the research tasks and strategy to design advanced wind and hydrokinetic energy systems. The paper applies the new Metric Space to several case studies, including large and small onshore wind turbines, floating and bottom-fixed offshore wind turbines, downwind rotors, multi-rotor and hybrid systems, airborne wind energy systems, wind farms and tidal energy converters.

17 WIND ENERGY↗
DOE OSTI2023

Factors Influencing Propensity for Stress Relaxation Cracking in Inconel® Alloy 740H® and Practical Guidance for Applications

Inconel® alloy 740H® (UNS N07740) was the first age-hardenable nickel-based alloy approved by the ASME Boiler & Pressure Vessel Code for use in pressure-boundary applications. In recent years, advanced energy systems such as supercritical CO2 power cycles have utilized alloy 740H in large demonstration projects driven by the requirement for higher fluid temperatures and pressures. Stress relaxation cracking (SRxC) following post-weld heat-treatment (PWHT), also known as strain age cracking (SAC), has been identified in a limited number of weldments during these industrial builds resulting in focused research to further clarify factors influencing this cracking tendency. This paper will summarize some of the findings from shop and field fabrication leading to successful welds and characteristics of observed SRxC. Laboratory experiments supported by microstructural characterization will be presented to highlight the importance of variables such as strain, material starting condition, and PWHT temperatures. Finally, the results will be summarized within the context of practical guidance for industry to successfully weld the material in boiler, heat exchanger, and piping applications.

14 SOLAR ENERGY↗
DOE OSTI2016

Fusion of CT Angiography or MR Angiography with Unenhanced CBCT and Fluoroscopy Guidance in Endovascular Treatments of Aorto-Iliac Steno-Occlusion: Technical Note on a Preliminary Experience

AimTo evaluate the feasibility of image fusion (IF) of pre-procedural arterial-phase CT angiography or MR angiography with intra-procedural fluoroscopy for road-mapping in endovascular treatment of aorto-iliac steno-occlusive disease.Materials and MethodsBetween September and November, 2014, we prospectively evaluated 5 patients with chronic aorto-iliac steno-occlusive disease, who underwent endovascular treatment in the angiography suite. Fusion image road-mapping was performed using angiographic phase CT images or MR images acquired before and intra-procedural unenhanced cone-beam CT. Radiation dose of the procedure, volume of intra-procedural iodinated contrast medium, fluoroscopy time, and overall procedural time were recorded. Reasons for potential fusion imaging inaccuracies were also evaluated.ResultsImage co-registration and fusion guidance were feasible in all procedures. Mean radiation dose of the procedure was 60.21 Gycm2 (range 55.02–63.75 Gycm2). The mean total procedure time was 32.2 min (range 27–38 min). The mean fluoroscopy time was 12 min and 3 s. The mean procedural iodinated contrast material dose was 24 mL (range 20–40 mL).ConclusionsIF gives Interventional Radiologists the opportunity to use new technologies in order to improve outcomes with a significant reduction of contrast media administration.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Balloon-Occluded Antegrade Transvenous Sclerotherapy to Treat Rectal Varices: A Direct Puncture Approach to the Superior Rectal Vein Through the Greater Sciatic Foramen Under CT Fluoroscopy Guidance

Rectal varices occur in 44.5 % of patients with ectopic varices caused by portal hypertension, and 48.6 % of these patients are untreated and followed by observation. However, bleeding occurs in 38 % and shock leading to death in 5 % of such patients. Two patients, an 80-year-old woman undergoing treatment for primary biliary cirrhosis (Child-Pugh class A) and a 63-year-old man with class C hepatic cirrhosis (Child-Pugh class A), in whom balloon-occluded antegrade transvenous sclerotherapy was performed to treat rectal varices are reported. A catheter was inserted by directly puncturing the rectal vein percutaneously through the greater sciatic foramen under computed tomographic fluoroscopy guidance. In both cases, the rectal varices were successfully treated without any significant complications, with no bleeding from rectal varices after embolization.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2016

Intraarticular Sacroiliac Joint Injection Under Computed Tomography Fluoroscopic Guidance: A Technical Note to Reduce Procedural Time and Radiation Dose

PurposeA technique for computed tomography fluoroscopy (CTF)-guided intraarticular (IA) sacroiliac joint (SIJ) injection was devised to limit procedural time and radiation dose.MethodsOur Institutional Review Board approved this retrospective analysis and waived the requirement for informed consent. Overall, 36 consecutive diagnostic or therapeutic IA SIJ injections (unilateral, 20; bilateral, 16) performed in 34 patients (female, 18; male, 16) with a mean age of 45.5 years (range 20–76 years) under CTF guidance were analyzed, assessing technical success (i.e., IA contrast spread), procedural time, and radiation dose.ResultsAll injections were successful from a technical perspective and were free of serious complications. Respective median procedural times and effective doses of SIJ injection were as follows: unilateral, 5.28 min (range 3.58–8.00 min) and 0.11 millisievert (mSv; range 0.07–0.24 mSv); and bilateral, 6.72 min (range 4.17–21.17 min) and 0.11 mSv (range 0.09–0.51 mSv).ConclusionsGiven the high rate of technical success achieved in limited time duration and with little radiation exposure, CTF-guided IA SIJ injection is a practical and low-risk procedure.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

Percutaneous Biopsy of Retrobulbar Masses: Anatomical Considerations and MRI Guidance

PurposeObtaining adequate tissue from retrobulbar masses remains a challenge. To this end, a new method of retrobulbar mass biopsy using MRI guidance is presented.Materials and MethodsTwo patients (7- and 71-year-old male) with indeterminate retrobulbar masses underwent bioptic and cytological samplings using MR-compatible 18G and 20–22G needles, and multi-planar MR fluoroscopy. An inferior approach was taken to avoid injury to the optic nerve and ophthalmic arteries.ResultsThe two biopsies were completed without complication. The core biopsy resulted in a final diagnosis, whereas the cytological sampling was non-diagnostic.ConclusionPercutaneous MR-guided retrobulbar mass biopsy proved to be feasible and safe in the two cases described in this report.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2018

Whole-Gland Prostate Cancer Cryoablation with Magnetic Resonance Imaging Guidance: One-Year Follow-Up

PurposePatients who develop prostate cancer after prior abdominal perineal resection are poor surgical candidates, and have limited treatment options. Therefore, our goal is to present results from a single institutional experience of four patients who underwent whole gland MRI-guided cryoablation with a history complicated by prior abdominoperineal resection.Materials and MethodsFour MRI-guided cryoablative treatments (mean age 64, range 59-69 years) for primary and locally recurrent prostate adenocarcinoma were retrospectively reviewed in patients with prior abdominal perineal resection for colorectal cancer (3) and juvenile polyposis (1). Average prostate volume prior to ablation was 23 cc, with an average PSA of 5.6 ng/mL. For each gland, 7-10 cryoprobes were placed approximately 0.5 cm apart in the prostate gland under MRI guidance by a transperineal approach with 3-4 freeze-thaw cycles performed. Each patient had follow up imaging and PSA measurements out to 12 months post ablation.ResultsAll four patient’s PSA dropped below 0.1 ng/mL at 3-6 month post-ablation and remained at these levels at 12 months. Three of the 4 patients had PSA measurements to 33 months post-ablation, with no evidence of recurrence. No patient developed urinary incontinence due to the whole gland cryoablation.ConclusionWith all four patients in our study having undetectable PSAs 12 months post ablation, and with no patient developing urinary incontinence due to the cryoablation, MRI-guided cryoablation appears to be a promising treatment option in patients who are poor surgical candidates due to prior pelvic surgery and/or radiation.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2018

Image Fusion Guidance with Pre-procedural CT with Real-Time Fluoroscopy for Adrenal Venous Sampling

PurposeTo assess the effectiveness of image fusion guidance (IF) with pre-procedural computed tomography (CT) with intraprocedural fluoroscopy for adrenal venous sampling (AVS).Materials and MethodsAVS before and after ACTH stimulation including bilateral segmental sampling of effluent tributaries was performed in 62 patients with IF. A 3D volume rendering image, including adrenal glands and veins extracted from previously obtained contrast-enhanced CT images, was manually registered to the real-time X-ray fluoroscopy. The technical success rates, procedure time, radiation exposure, and volume of contrast medium used were compared with 49 patients who underwent AVS without IF.ResultsNo significant differences in the technical success rates with and without IF were observed (98.4 vs. 91.8% for the right adrenal veins, p = 0.168, and 98.4 vs. 100% for the left adrenal veins, p = 1.000). The procedure time with IF was significantly shorter than that without IF (95.6 ± 18.8 vs. 108.4 ± 20.0 min, p = 0.001). The total dose-area product with IF was significantly lower than that without IF (43.1 ± 30.7 vs. 72.2 ± 45.3 Gy cm{sup 2}, p < 0.001). The contrast medium volume used with IF was significantly lower than that without IF (54.6 ± 21.9 vs. 65.7 ± 27.6 mL, p = 0.020).ConclusionsAlthough the contribution to improving the technical success rates was small in our study, IF can effectively reduce procedure time, radiation exposure, and volume of contrast medium during AVS.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Image Fusion Guidance for In Situ Laser Fenestration of Aortic Stent graft for Endovascular Repair of Complex Aortic Aneurysm: Feasibility, Efficacy and Overall Functional Success

Objective: To evaluate feasibility, efficacy and overall functional success of image fusion guidance during laser-assisted in situ fenestration of aortic stent graft (LISFAS) for endovascular repair of complex aortic aneurysm (complex-EVAR) in a prospective study. Methods: Between September 2016 and July 2018, 20 patients were included and treated with LISFAS for complex-EVAR. Aortic aneurysms were either para-renal (n = 15) or thoraco-abdominal (n = 5) with 57 mm [first quartile: 54; third quartile: 68] median aneurysm diameter in 69 years [68;78] patients. All interventions were performed using the same angiographic system and 3D image fusion software for overlying pre-intervention CTA on per-intervention 2D fluoroscopy with cone-beam CT images to display target vessels ostia. Results: LISFAS for complex-EVAR with image fusion was performed in all patients, and no endovascular intervention required conversion to an open aortic repair. LISFAS of all target vessels was feasible in 18 patients (90%); 48 fenestrations out of 50 were performed successfully. Two fenestrations failed for renal arteries in two patients. Median ischemic times were as follows: 34 min [25;43] for superior mesenteric artery; 69 min [56;83] for left renal artery; 73 min [36;102] for right renal artery; and 93 min [89;96] for the celiac trunk. Median intervention and fluoroscopy times, iodinated contrast volume and X-ray exposure were 180 min [150;180], 74 min [64;87], 80 mL [59;113] and 338 Gy.cm{sup 2} [259;495], respectively. Efficacy was found in 17 patients (85%) on one-week follow-up CTA: Two patients had type 1 and 3 endoleaks, respectively, that were successfully embolized. Overall functional success was 90%. Median hospitalization stay was 9 days [8, 17]. The 30-day safety analysis was 90% (n = 2 deaths) owing to an undetermined cause and to bowel ischemia after low flow in intensive care unit. Conclusions: LISFAS using image fusion was feasible, efficient and overall functionally successful for complex-EVAR in this preliminary study.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Assessment of Interfraction Patient Setup for Head-and-Neck Cancer Intensity Modulated Radiation Therapy Using Multiple Computed Tomography-Based Image Guidance

Purpose: Various image guidance systems are commonly used in conjunction with intensity modulated radiation therapy (IMRT) in head-and-neck cancer irradiation. The purpose of this study was to assess interfraction patient setup variations for 3 computed tomography (CT)-based on-board image guided radiation therapy (IGRT) modalities. Methods and Materials: A total of 3302 CT scans for 117 patients, including 53 patients receiving megavoltage cone-beam CT (MVCBCT), 29 receiving kilovoltage cone-beam CT (KVCBCT), and 35 receiving megavoltage fan-beam CT (MVFBCT), were retrospectively analyzed. The daily variations in the mediolateral (ML), craniocaudal (CC), and anteroposterior (AP) dimensions were measured. The clinical target volume-to-planned target volume (CTV-to-PTV) margins were calculated using 2.5Σ + 0.7 σ, where Σ and σ were systematic and random positioning errors, respectively. Various patient characteristics for the MVCBCT group, including weight, weight loss, tumor location, and initial body mass index, were analyzed to determine their possible correlation with daily patient setup. Results: The average interfraction displacements (± standard deviation) in the ML, CC, and AP directions were 0.5 ± 1.5, −0.3 ± 2.0, and 0.3 ± 1.7 mm (KVCBCT); 0.2 ± 1.9, −0.2 ± 2.4, and 0.0 ± 1.7 mm (MVFBCT); and 0.0 ± 1.8, 0.5 ± 1.7, and 0.8 ± 3.0 mm (MVCBCT). The day-to-day random errors for KVCBCT, MVFBCT, and MVCBCT were 1.4-1.6, 1.7, and 2.0-2.1 mm. The interobserver variations were 0.8, 1.1, and 0.7 mm (MVCBCT); 0.5, 0.4, and 0.8 mm (MVFBCT); and 0.5, 0.4, and 0.6 mm (KVCBCT) in the ML, CC, and AP directions, respectively. The maximal calculated uniform CTV-to-PTV margins were 5.6, 6.9, and 8.9 mm for KVCBCT, MVFBCT, and MVCBCT, respectively. For the evaluated patient characteristics, the calculated margins for different patient parameters appeared to differ; analysis of variance (ANOVA) and/or t test analysis found no statistically significant setup difference in any direction. Conclusions: Daily random setup errors and CTV-to-PTV margins for treatment of head-and-neck cancer were affected by imaging quality. Our data indicated that larger margins were associated with MVFBCT and MVCBCT, compared with smaller margins for KVCBCT. IGRT modalities with better image quality are encouraged in clinical practice.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Stereotactic Ablative Radiation Therapy for Subcentimeter Lung Tumors: Clinical, Dosimetric, and Image Guidance Considerations

Purpose: Use of stereotactic ablative radiation therapy (SABR) for subcentimeter lung tumors is controversial. We report our outcomes for tumors with diameter ≤1 cm and their visibility on cone beam computed tomography (CBCT) scans and retrospectively evaluate the planned dose using a deterministic dose calculation algorithm (Acuros XB [AXB]). Methods and Materials: We identified subcentimeter tumors from our institutional SABR database. Tumor size was remeasured on an artifact-free phase of the planning 4-dimensional (4D)-CT. Clinical plan doses were generated using either a pencil beam convolution or an anisotropic analytic algorithm (AAA). All AAA plans were recalculated using AXB, and differences among D95 and mean dose for internal target volume (ITV) and planning target volume (PTV) on the average intensity CT dataset, as well as for gross tumor volume (GTV) on the end respiratory phases were reported. For all AAA patients, CBCT scans acquired during each treatment fraction were evaluated for target visibility. Progression-free and overall survival rates were calculated using the Kaplan-Meier method. Results: Thirty-five patients with 37 subcentimeter tumors were eligible for analysis. For the 22 AAA plans recalculated using AXB, Mean D95 ± SD values were 2.2 ± 4.4% (ITV) and 2.5 ± 4.8% (PTV) lower using AXB; whereas mean doses were 2.9 ± 4.9% (ITV) and 3.7 ± 5.1% (PTV) lower. Calculated AXB doses were significantly lower in one patient (difference in mean ITV and PTV doses, as well as in mean ITV and PTV D95 ranged from 22%-24%). However, the end respiratory phase GTV received at least 95% of the prescription dose. Review of 92 CBCT scans from all AAA patients revealed that the tumor was visualized in 82 images, and its position could be inferred in other images. The 2-year local progression-free survival was 100%. Conclusions: Patients with subcentimeter lung tumors are good candidates for SABR, given the dosimetry, ability to localize tumors with image guidance, and excellent local control.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Quality of Intensity Modulated Radiation Therapy Treatment Plans Using a {sup 60}Co Magnetic Resonance Image Guidance Radiation Therapy System

Purpose: This work describes a commercial treatment planning system, its technical features, and its capabilities for creating {sup 60}Co intensity modulated radiation therapy (IMRT) treatment plans for a magnetic resonance image guidance radiation therapy (MR-IGRT) system. Methods and Materials: The ViewRay treatment planning system (Oakwood Village, OH) was used to create {sup 60}Co IMRT treatment plans for 33 cancer patients with disease in the abdominal, pelvic, thorax, and head and neck regions using physician-specified patient-specific target coverage and organ at risk (OAR) objectives. Backup plans using a third-party linear accelerator (linac)-based planning system were also created. Plans were evaluated by attending physicians and approved for treatment. The {sup 60}Co and linac plans were compared by evaluating conformity numbers (CN) with 100% and 95% of prescription reference doses and heterogeneity indices (HI) for planning target volumes (PTVs) and maximum, mean, and dose-volume histogram (DVH) values for OARs. Results: All {sup 60}Co IMRT plans achieved PTV coverage and OAR sparing that were similar to linac plans. PTV conformity for {sup 60}Co was within <1% and 3% of linac plans for 100% and 95% prescription reference isodoses, respectively, and heterogeneity was on average 4% greater. Comparisons of OAR mean dose showed generally better sparing with linac plans in the low-dose range <20 Gy, but comparable sparing for organs with mean doses >20 Gy. The mean doses for all {sup 60}Co plan OARs were within clinical tolerances. Conclusions: A commercial {sup 60}Co MR-IGRT device can produce highly conformal IMRT treatment plans similar in quality to linac IMRT for a variety of disease sites. Additional work is in progress to evaluate the clinical benefit of other novel features of this MR-IGRT system.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

The dilemma of parotid gland and pharyngeal constrictor muscles preservation—Is daily online image guidance required? A dosimetric analysis

With margin reduction common in head and neck radiotherapy, it is critical that the dosimetric effects of setup deviations are quantified. With past studies focusing on the quantification of positional and volumetric changes of organs at risk (OARs), this study aimed to measure the dose delivered to these the parotid gland (PG) and pharyngeal constrictor muscles (PCMs) using cone beam computed tomography (CBCT). Furthermore, this investigation sought to establish a potential time trend of change in dose delivered to target volumes secondary to ascertaining the need for daily image guidance (IG) to reduce the dose burden to these important OARs. Intensity modulated radiotherapy (IMRT) plans for 5 locally advanced head and neck patients' plans were created and mapped to weekly CBCTs. Each plan was recalculated without heterogeneity correction allowing for dosimetric comparison. Dosimetric endpoints recorded to assess the effect of positional variation were as per ICRU 83 and included D{sub 95} and D{sub 98} for the target volumes, mean dose (MD) and V{sub 30} {sub Gy} for the PGs, and V{sub 50} {sub Gy} and MD for the PCMs. Results were deemed statistically significant if p < 0.05. No significant time trends were established for these OARs. A significant decrease in V{sub 50} {sub Gy} was observed for all PCMs (p < 0.001) on all CBCTs relative to the original plan. Regarding target volumes, a highly significant decrease in MD (MD = 20 Gy, CI: −20.310 to −19.820) in D{sub 98} of the high-dose planning target volume (PTV [70 Gy]; PTVD{sub 98%} = 70 Gy) for case 3 was found (p ≤ 0.001). A nonpredictable, yet significant dosimetric effect was found. A clinically acceptable balance must be achieved between OAR dosimetry and target coverage as can be achieved by frequent IG.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2014

Review of LCA studies of solid waste management systems – Part II: Methodological guidance for a better practice

Highlights: • We perform a critical review of 222 LCA studies of solid waste management systems. • We analyse the past LCA practice against the ISO standard and ILCD Handbook guidance. • Malpractices exist in many methodological aspects with large variations among studies. • Many of these aspects are important for the reliability of the results. • We provide detailed recommendations to practitioners of waste management LCAs. - Abstract: Life cycle assessment (LCA) is increasingly used in waste management to identify strategies that prevent or minimise negative impacts on ecosystems, human health or natural resources. However, the quality of the provided support to decision- and policy-makers is strongly dependent on a proper conduct of the LCA. How has LCA been applied until now? Are there any inconsistencies in the past practice? To answer these questions, we draw on a critical review of 222 published LCA studies of solid waste management systems. We analyse the past practice against the ISO standard requirements and the ILCD Handbook guidelines for each major step within the goal definition, scope definition, inventory analysis, impact assessment, and interpretation phases of the methodology. Results show that malpractices exist in several aspects of the LCA with large differences across studies. Examples are a frequent neglect of the goal definition, a frequent lack of transparency and precision in the definition of the scope of the study, e.g. an unclear delimitation of the system boundaries, a truncated impact coverage, difficulties in capturing influential local specificities such as representative waste compositions into the inventory, and a frequent lack of essential sensitivity and uncertainty analyses. Many of these aspects are important for the reliability of the results. For each of them, we therefore provide detailed recommendations to practitioners of waste management LCAs.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗