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Fuel-burning small engines have the potential to emit dangerous and potentially lethal concentrations of carbon monoxide when used in poorly ventilated environments. The North Carolina Office of the Chief Medical Examiner investigated seven cases from 2013 to 2020 involving lethal carbon monoxide from small internal combustion engines. Evaluation of percent carboxyhemoglobin saturation was determined in these case studies as ratios of carboxyhemoglobin to reduced hemoglobin, using HP 8453 and Agilent 8454 UV-Visible Spectrophotometers (Agilent Technologies, Santa Clara, CA, USA). Sources of carbon monoxide included a pressure washer, a propane-powered forklift, an inboard engine boat, a motorcycle, propane and kerosene heaters, and home-use generators. It was demonstrated during a death investigation that the Dräger X-am 2000 electrochemical gas monitor often used by first responders, falsely reacted to acetylene gas, initially misleading investigators to the source of the carbon monoxide. Educating first responders about not only the hazards of these unexpected carbon monoxide sources, but the limitations of their equipment, is a valuable goal of disseminating complete medical examiner case information. The details of these cases will educate first responders, the forensic science community, and public health leaders on potential small engine sources of carbon monoxide in death investigations, responder safety, and the limitations of portable air quality monitoring equipment during death investigation. [ABSTRACT FROM AUTHOR]

Pollutants degrade the performance of LiDAR sensors used in autonomous vehicles. Therefore, there is an urgent need to develop cleaning technology for these sensors. In this study, a solid-state LiDAR sensor was selected as a target and sprayed/dried with 2.5 g of a mixture of Arizona dust and Kaolin. To achieve optimal LiDAR cleaning performance, the washer pressure, spray time, spray angle, and target point were selected as major variables. Additionally, an optimal cleaning solution for each spray was formed via the design of experiments and optimization techniques. Model suitability was observed for the second spray through to the fourth. The cleaning rate increased with the washer pressure and spray time. The influence of these variables decreased as the number of sprays increased. The spray angle and target point exhibited no significant influence, but excellent cleaning was observed in some central areas. Verification test results were within 3% for the second through fourth sprays, indicating reliability. This study used a designed experiment with 30 scenarios to reveal optimized conditions for protecting the sensor performance from external visibility obstructions. Disclosing the optimization method lowers the barrier for sensor cleaning manufacturers to develop their own technology, which ultimately enhances safer and more efficient autonomous driving. [ABSTRACT FROM AUTHOR]

The quality and safety of dairy products are highly valued by consumers and dairy manufacturers, which is mainly ensured by thorough cleaning of dairy production equipment. Milk fouling can cause pipes to clog and reduce transmission. Incomplete cleaning can cause microbial breeding, which will affect the quality and safety of dairy products. To achieve efficient and rapid cleaning of dairy processing equipment, cleaning agents have always been a necessary choice for dairy and food enterprises. This paper describes the production mechanism of milk fouling, the cleaning mechanism by cleaning agents, and the cleaning process. Development of cleaning agents are introduced in detail, include compound alkaline/acid/neutral cleaning agents, enzyme cleaning agents and cleaning additives. The factors affecting cleaning efficiency are also viewed, which include type and dosage of cleaning agents, cleaning process (cleaning time, cleaning liquid temperature, cleaning fluid flow rate), and other influencing factors (cleaning fluid pressure, Reynolds number and shear stress, surface types). Four aspects are reviewed in this manuscript, include cleaning objects (milk fouling), cleaning substances (cleaning agents), how to clean (cleaning mechanism) and how to clean efficiently (cleaning influencing factors), which provides a valuable reference for the improvement of the dairy cleaning process. [ABSTRACT FROM AUTHOR]

In response to the challenges posed by the difficult cleaning of tunnel retro-reflective rings and the unsuitability of existing climbing robots for ascending tunnel retro-reflective rings, a tunnel retro-reflective ring cleaning robot is proposed. Firstly, based on the analysis of the operational and environmental characteristics and functional requirements inside the tunnel, the design and planning of the robot's main framework, motion system, cleaning mechanism, and intelligent detection system are conducted to evaluate its walking ability under various working conditions, such as aluminum plate overlaps and rivet protrusions. Subsequently, stability analysis is performed on the robot. The static analysis explored conditions that can make the climbing robot stable, the dynamic analysis obtained the minimum driving torque and finally, verified the stability of the robot through experiments. After that, by changing the material and thickness of the main framework for deformation simulation analysis, the optimal parameters to optimize the design of the main framework are found. Finally, the three factors affecting the cleaning effect of the robot are discussed by the response surface method, and single factor analysis and response surface regression analysis are carried out, respectively. The mathematical regression model of the three factors is established and the best combination of the three factors is found. The cleaning effect is best when the cleaning disc pressure is 5.101 N, the walking wheel motor speed is 36.93 rad/min, and the cleaning disc motor speed is 38.252 rad/min. The development of this machine can provide equipment support for the cleaning of tunnel retro-reflective rings, reducing the requirement of manpower and material resources. [ABSTRACT FROM AUTHOR]

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In this paper, in view of the existing mechanical sand cleaning technology, circulating sand flushing technology, and negative pressure sand cleaning technology, which cannot establish circulation, the pump lift is limited, the sand cleaning efficiency is low, and many other problems when cleaning the sand in deep wells that are prone to leakage, a new type of sand cleaning system that can realize the local circulation and storage of sand fluid at the bottom of the well is designed. The critical problem to be solved in this design is how to simultaneously meet the dual requirements of local circulation and storage, that is, how to coordinate the contradiction between gravel carrying and settlement. Therefore, studying the mechanism of sand transport and settlement in the new type of sand cleaning cylinder is necessary. The discrete phase model of the sand liquid flowing in the sand cleaning cylinder was established using EDEM-FLUENT. The numerical simulation and analysis of the movement law of sand grains, the trajectory line clouds of sand grains, and the variation law of sand settling rate, sand mass flow rate, and sand-carrying liquid flow rate under different working parameters were obtained. The conclusion shows that when the mass flow rate of sand particles is 0.5–0.8 kg/s, and the flow rate of sand-carrying liquid is 0.5– 1 m/s, the grit removal effect of the sand cleaning cylinder is better. In order to verify the sand cleaning effect of this new sand cleaning system and the accuracy of the numerical analysis model, the ground simulation test platform of the sand cleaning cylinder was built, and simulated sand cleaning tests were carried out under different sand particle sizes and different sand-carrying fluid flow rates. The test results show that the new sand cleaning system clears sand well. Comparing the numerical simulation results with the experimental results, the two have the same variation pattern, which verifies the feasibility of this new sand cleaning system and the correctness of the numerical analysis model. The study provides a new sand cleaning system solution, which solves the problem that existing sand cleaning techniques cannot quickly and efficiently clean up sunken sand from leaking oil and gas wells and provides a basis for the selection of field operating parameters for the new sand cleaning system. [ABSTRACT FROM AUTHOR]

Background. Cleaning symbiotic interactions are an important component of coral reef biodiversity and the study of the characteristics of these interacting species networks allows to assess the health of communities. The coral reefs of Jardines de la Reina National Park (JRNP) are subject to a protection gradient and there is a lack of knowledge about the effect of different levels of protection on the cleaning mutualistic networks in the area. The present study aims to characterize the mutualistic cleaning networks in the reefs of JRNP and to assess the potential effect of the protection gradient on their characteristics. Methods. We visited 26 reef sites distributed along the National Park and performed 96 band transects (50 m × 4 m). Low, medium and highly protected regions were compared according to the number of cleaning stations and the abundance and number of species of clients and cleaners associated with them. Additionally, we built interaction networks for the three regions and the entire archipelago based on a total of 150 minutes' video records of active cleaning stations. Weassessed ecological networks characteristics (specialization, nestedness) using network topological metrics. Results. We found a high diversity and complex cleaning interaction network with 6 cleaner species and 39 client species, among them, the threatened grouper Epinephelus striatus was one of the most common clients. Noclear effect of the protection level on the density, abundance or diversity of cleaners and clients was detected during this study. However, we found that the network structure varied among regions, with the highly protected region being more specialized and less nested than the other regions. Our research reveals some patterns that suggest the effect of fishing pressure on cleaning symbiosis, as fishing may reduce the abundance and composition of client species, especially those that are targeted by fishers. However, fishing pressure may not be the main factor influencing cleaning symbiosis inside of the National Park, as other factors, such as habitat quality or environmental conditions may have stronger effects on the demand for cleaning services and the interactions between cleaners and clients. Our research provides insights into the factors that influence cleaning symbiosis and its implications for coral reef conservation and management. [ABSTRACT FROM AUTHOR]

To solve the problem of low efficiency of manual harvesting of green soybeans and lack of adaptable harvesters, in this study, a brushing-type green soybean harvester was designed. The comb-brushing type green soybean pod harvesting equipment is composed of a front-mounted separation drum, a full-width material delivery mechanism, a negative pressure cleaning system, and a stalk-pod separation system. Based on the operation requirements of the front-mounted brushing-type detachment drum, the drum parameters, parameters of comb arrangement, and structural parameters of the comb, the force analysis in detachment was performed. By taking the pod detachment rate and damage rate as the response indexes, the rotational speed of the drum, the travel speed of the device, and teeth distance as influencing factors, a three-factor five-level orthogonal rotary combination test was carried out by the software Design-Expert. By establishing mathematical regression models for various influencing factors and evaluation indicators, conducting variance analysis and significance analysis on the response indicators of each factor, the optimal parameters were obtained at a rotational speed of teeth of 397.36 rpm/min, minimum axial teeth distance of 4.8 mm and travel speed of the device of 0.5 m/s. Field test results showed that, under the optimal parameter combination, the pod detachment rate was 94%, the damage rate was 3.04%, the harvesting efficiency was greater than 0.187 hm2/h, and impurity content was less than 7.8%, all of which met the design and usage requirements. The research results can provide a reference for the design of soybean harvesters. [ABSTRACT FROM AUTHOR]

We aim to develop a floor-cleaning design by exploiting oscillating bubbles combined with ambient pressure waves to clean various surfaces. Previous studies of this method in lab settings have proven its efficacy, but practical applications, especially concerning real-world conditions like dirt surfaces, remain largely unprobed. Our findings indicate that, excluding a configuration with a heavy mass bottom transducer, all tested configurations achieved approximately 60–70% cleaning performance. A slight improvement in cleaning performance was observed with the introduction of microbubbles, although it was within the error margin. Particularly noteworthy is the substantial reduction in water consumption in configurations with a water pocket, decreasing from 280 mL to a mere 3 mL, marking a significant step toward more environmentally sustainable cleaning practices, such as reduced water usage. This research provides implications for real-world cleaning applications, promising an eco-friendly and efficient cleaning alternative that reduces water usage and handles a variety of materials without causing damage. [ABSTRACT FROM AUTHOR]

Cake washing has been used to remove compounds trapped in the pores of a filter cake. These compounds could be desired products that should be recovered. Cake washing and electrowashing have been studied and found to present many benefits, but in some cases washing filter cakes can be a slow process. In this work, electrowashing (EW) and pressure electrowashing (PEW) were for the first time applied to enhance the liquid flowing in the the algal filter cake, which has a very high specific resistance and low washing velocity. The new EW and PEW processes were compared with conventional pressure washing (PW) of Arthrospira platensis microalgae. Washing was carried out to extract desired biocompounds (CPC, APC and proteins) from the filter cake. The study showed that the use of a constant direct current (60 A/m2) coupled with the effect of an applied hydraulic pressure was an effective way to increase the cake washing kinetics. It also demonstrated that it was possible to extract proteins and pigments by applying the washing by displacement technique. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present article outlines the development of a semi‐analytical model devoted to predict the pressure drop induced by clean pleated high‐efficiency particulate air (HEPA) filters. Both experimental measurements and numerical simulations are used to characterize the velocity field in the pleat channel. On this basis, a semi‐analytical model is derived to determine the gas flow within the pleat channel. This analytical formulation is used to predict the air pressure evolution according to filtration velocity in the pleat. This model is then validated on the basis of comparisons with measurements found in the scientific literature for different kinds of HEPA filters with different pleat geometries. This model is easy to use, fast to run compared to standard computational fluid dynamics (CFD) approaches, and is in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Maintenance has a significant impact on permeable pavements' service life. Proper cleaning procedures include pressure washing and heavy-duty wet/dry vacuum to remove accumulated sediment and maintain permeability. Aiming to analyze the influence of sediment type and size on the clogging process and the importance of preventive maintenance, six experimental permeable pavement modules were assessed. Pairs of in-situ Pervious Concrete (PC), Permeable Interlocking Concrete Pavement (PICP) and Permeable Interlocking Pervious Concrete Pavement (PIPCP) were monitored over two consecutive periods: i) under natural clogging process; ii) accelerated clogging under sand and clay sediment types. At the end of both periods, all modules received maintenance through water pressure washing. The results showed a reduction of up to 80% in the surface infiltration capacity during the natural clogging period, but that most of it could be recovered using pressure washing. Result in all situations also reinforced that periodic cleaning every 4-6 months, even with just pressure washing, as a key factor to extend permeable pavements' life cycle. [ABSTRACT FROM AUTHOR]

[Display omitted] • Using a pressure washing system shortens the length of time for delamination. • Fractional factorial design is used to screen factors. • Particle size, morphology, and acid leaching of products are evaluated. Recycling cathode materials from spent lithium-ion batteries has the potential to reduce damages to the environment and human health due to hazardous waste treatment, and mitigate supply risks of raw materials. Related political incentives or regulations have led to increased research and development efforts on cathode recycling. Promising approaches include direct recycling and hydrometallurgical processes, where delamination is the first step after collection of cathodes. In this study, we examined a pressure washing system's ability to harvest cathode materials. A high-pressure water jet provides strong forces to overcome the adhesion provided by organic binders. Four factors (water pressure, distance between nozzle and cathode, incident angle of water jet, and nozzle type) were investigated using a 34-1 fractional factorial design to screen important parameters and find the optimal conditions. Compared with other delamination processes where chemical reagents and heating are involved, the chemical-free pressure washing system can achieve separation in a few seconds (∼74 min/m2) at room temperature, which remarkably improves the efficiency of delamination. The particle size of recycled products (D50 of 31.87 μ m) is significantly reduced without Al contamination from current collectors or morphological damages. In addition, three types of recycled cathode materials were used as inputs for the acid leaching process. High leaching efficiencies of lithium (>90 %) and cobalt (>85 %) suggest that the pressure washing system could be a practical, economical, and eco-friendly pretreatment process to harvest cathode materials. [ABSTRACT FROM AUTHOR]

In the light-activated work-holding devices, hardened adhesive residues on the fixture plate need to be removed to make it available for the subsequent work holding. There are several ways to remove the cured adhesive from the gripper, such as laser-based degradation, and softening and removing with high temperature pressured water wash. These processes are associated with the generation of carbon black, affecting transparency which compromises the efficiency of the light-activated device. A novel peripheral grinding-based cleaning process has been developed to strip the adhesive from the fixture plate. The present research is aimed to analyze the effect of variation in grinding parameters, viz., spindle speed, feed, depth of cut, and the grain size of the grinding wheel on the temperature of the adhesive being ground and cleaning of the adhesive-filled channel. Aggressive values of grinding parameters are selected to achieve the desired removal of adhesive, putting a step towards sustainability. Moreover, a comprehensive investigation of the temperature of the grinding zone and the grinding wheel is made by inspecting the effective cleaning of the cured adhesive-filled channel. Higher values of spindle speed (11.57 m/s) and feed (0.406 mm/rev) resulted in an improved, cleaned surface of the ground adhesive-filled channel. Moreover, the grinding wheel with a more prominent grain size (46/Ø 0.35 mm) and porosity was proved to be more effective in the cleaning process by reducing and maintaining the grinding temperature (~52 °C) of the adhesive-filled channel. [ABSTRACT FROM AUTHOR]

In order to improve the single-grain seeding rate of the pneumatic single seed metering device, an airflow seed cleaning device was designed in combination with positive pressure airflow. The influence of the position of the seed cleaning mechanism on the seed cleaning effect is theoretically analyzed and a flow field simulation test analysis of different nozzle structures was carried out by using Fluent software (ANSYS, Inc., Canonsburg, PA, USA). The results of this test show that a nozzle with a Witoszynski curve has good airflow concentration and uniform air pressure distribution. In order to verify the performance of the seed cleaning mechanism, a 0.7 times coated seed (hybrid rice Wuyou 1179) was used as the test material and a quadratic regression test with three levels was carried out with the rotation speed of the seed plate, the negative pressure of the suction chamber, and the positive pressure of the seed cleaning as the test factors. The results showed that when the speed of sucking plate was 30 r/min, the negative pressure of the suction chamber was 1.8 kPa and the positive pressure of the seed cleaning was 0.2 kPa; the seeding effect was at its best and the qualified rate of the seed metering device was the highest at 86.43%, the minimum leakage rate was 3.81%, and the multiple rate was 9.76%. The proposed seed cleaning mechanism effectively improves the accuracy of seeding and provides a certain theoretical basis for the single-grain sowing of hybrid rice. [ABSTRACT FROM AUTHOR]

In recent years, the electrostatic-fabric integrated precipitator has been widely used, and the dust filtration performance of the core component filter bag is the most important factor affecting its dust removal efficiency. In this work, the dynamic dust removal performance of different types of filter media and different experimental conditions were studied on the filter media filtration performance test platform. The experimental study of the filtration performance of different types of filter media showed that the filtration performance stability of polyphenylene sulfide (PPS) filter media was better than that of polyimide (PI) and polytetrafluoroethylene (PTFE) filter media. Increasing the mass per unit area of the filter media had obvious advantages in the short term, and the impregnation process was beneficial to the filter performance of the filter media. Membrane-coated filter media had the best filtration performance, gradient filter media filtration performance was the second, followed by conventional filter media, ordinary blended, and ultrafine blended filter media. Studies with different experimental conditions found that the filtration efficiency increased with increasing resistance, was not significantly affected by changes in inlet dust concentration, but decreased with the increasing filtering velocity. This experimental results provided an important basis for the selection of filter bags for the electrostatic-fabric integrated precipitator project. [ABSTRACT FROM AUTHOR]

Pervious concrete (PC) pavement has been widely accepted as a green infrastructure but is prone to clogging. This study comparatively investigated sand and clay clogging mechanisms of PC and vertical sediment distributions of sand-clogged and clay-clogged PCs. Clay and three sizes of sand were used to clog PC under two exposure methods (no drying and drying). X-ray computed tomography (CT) was used to scan the clogged samples before and after 30 pressure washing cycles. The clogged permeability and permeability after each washing cycle were measured. The clogging patterns of sand depend mainly on sand particle sizes relative to PC pore sizes. The applied fine sand, coarse sand, and medium sand cause easy-passing clogging, surface clogging, and full-depth clogging, respectively. After clay clogging, more than 77% of the total retained clay occurs within the vertical region 24–72 mm below the sample surface; the most clogging (the lowest-permeability layer) occurs at a depth of approximately 48 mm. The dried clay retained within the region 40–120 mm below the surface (especially within the lowest-permeability layer) is hard to wash away because the drying process increases the cohesion of internal clay particles and clay adhesion to the rough, tortuous pore wall of PC. The clogged normalized permeability of 0.154 and permeability recovery ratio of 4.91% in dried clay-clogged samples are lowest among all the samples. However, pressure washing readily washes away the retained undried clay. Accordingly, it is recommended that pressure washing is used to eliminate the clogging effect of dried clay before hot, sunny exposure conditions dry the retained clay. This study provides evidence for developing effective pavement maintenance strategies. [ABSTRACT FROM AUTHOR]

Centrifuge testing data are presented to elucidate the influence of particle size and gradation on liquefaction potential and dynamic response. The physical, index, and material properties of nine test soil mixtures, sharing a common geologic origin and ranging in D50 from 0.18 to 2.58 mm and Cu from 1.53 to 9.86, were quantified and compared to the range of values exhibited by clean sands in the literature. Each centrifuge model was subjected to 15 dynamic loading events across a range of relative density and Arias intensity levels. The high permeability of the poorly graded soils prevented flow liquefaction; however, the gap and well-graded soils generated excess pore pressures similar to clean sands even though large particles were present. Despite similar pore pressure responses, the gap and well-graded test soils exhibited lower cumulative volumetric strains than the clean sand because of enhanced dilation. The tendency for the gap and well-graded soils to dilate is theorized to stem from their enhanced packing efficiency and increased shear stiffness. [ABSTRACT FROM AUTHOR]

Copyright of China Surfactant Detergent & Cosmetics (1001-1803) is the property of China Surfactant Detergent & Cosmetics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] • A coupled cleaning model (rinsing + backwash) was developed. • The model also could be used in a single rinsing or backwash process. • The cleaning mechanism was systematically studied in coupled cleaning. • Coupled cleaning possessed higher cleaning efficiency compared with single cleaning. • The optimal operating conditions for the coupled cleaning process were determined. Coupled cleaning (rinsing + backwash) during the constant flow rate process is an effective method for alleviating the membrane fouling. However, there is a lack of in-depth studies on the coupled cleaning process, especially for accurate descriptions of the variation of the trans-membrane pressure (p clean (t)). In this paper, a model based on the composite mechanism (open pores, loosen the cake and remove the cake) was first developed to describe the variation in p clean (t) during the coupled cleaning process for a 0.1 μm polyacrylonitrile (PAN) membrane fouled with activated sludge. Moreover, the model was validated by using different foulants (yeast, bovine serum protein, sodium alginate and humic acid), membranes (0.1 μm polyethersulfone (PES) and 0.1 μm polyvinylidene (PVDF) membranes). The results showed that the variation in p clean (t) could be accurately described during the coupled cleaning process under different backwash strengths (0.5, 1, 1.5 and 2) (R2 ≥ 0.997) or cross-flow velocities (0.05, 0.11, 0.17 and 0.22 m/s) (R2 ≥ 0.994). Moreover, the coupled cleaning process was divided into three stages: (1) p clean (t) decreased rapidly (open pores, loosen the cake and remove the cake). (2) p clean (t) decreased slowly (remove the cake) and (3) p clean (t) was almost unvaried (without open pores, loosen the cake and remove the cake). In addition, the model could also be applied to the single rinsing or backwash process. This model provided a theoretical basis for the membrane high-efficiency and energy-saving cleaning processes in MBRs. [ABSTRACT FROM AUTHOR]

In the field of industrial dedusting, incomplete cartridge cleaning and excessive pressure drop are main problems faced by cartridge dust collectors. The conventional way of cleaning dust accumulated on a cartridge is to spray pulsed airstream from a nozzle installed at the top of cartridge. However, this method has limited effect on sticky or moist dust. This article experimentally investigates the pulse-jet cleaning effect of a double-nozzle system arranged at the bottom and top of the cartridge respectively. Results show that the cleaning effect of the double-nozzle system was much better than that of the conventional single-nozzle system. At 0.3 MPa tank pressure, the mean residual pressure drop and dust emission concentration in the top-bottom simultaneous cleaning mode using double-nozzle system decreased by 24.32% and 12.91% respectively, compared with those in the top-only cleaning mode. At higher tank pressures (> 0.5 MPa), the top-bottom successive cleaning mode exhibited better effects. [Display omitted] • A double-nozzle pulse jet cleaning system for filter cartridges is presented. • Impact of cleaning parameters on pressure drop was investigated experimentally. • The best choice of cleaning modes at a specific tank pressure was determined. [ABSTRACT FROM AUTHOR]

Canopy defoliation is an important source of disturbance in forest ecosystems that has rarely been represented in large-scale manipulation experiments. Scalable crown to canopy level experimental defoliation is needed to disentangle the effects of variable intensity, timing, and frequency on forest structure, function, and mortality. We present a novel pressure-washing-based defoliation method that can be implemented at the canopy-scale, throughout the canopy volume, targeted to individual leaves or trees, and completed within a timeframe of hours or days. Pressure washing proved successful at producing consistent leaf-level and whole-canopy defoliation, with 10%–20% reduction in leaf area index and consistent leaf surface area removal across branches and species. This method allows for stand-scale experimentation on defoliation disturbance in forested ecosystems and has the potential for broad application. Studies utilizing this standardized method could promote mechanistic understanding of defoliation effects on ecosystem structure and function and development of synthetic understanding across forest types, ecoregions, and defoliation sources. [ABSTRACT FROM AUTHOR]