Wet Suit Research Articles

Energy-efficient crumb rubber drying by heat recovery and solar air heating

Natural rubber is a key agro-industrial product in Asia, Africa, America, and Oceania, with widespread applications (e.g. tires, latex gloves, wet suits). The energy consumption of the traditional rubber drying process is very high and improvements should be investigated to both reduce the energy consumption, and reduce the cost of the rubber processing. The research investigated both heat recovery and solar air heating (SAH) to minimize the energy consumption of the drying process. A complete assessment of an industrial rubber drying plant in China demonstrated that a heat recovery can reduce the energy consumption by 16 to 44%. If moreover SAH is applied, further energy savings can be achieved. A pilot-scale SAH was tested. Its solar transfer efficiency was between 30% and 50%. Experimental data were theoretically validated, and used in a scale-up design strategy, resulting in an overall drying energy saving of 60 to 77%. The corresponding total investment and payback period are 300 and 420 k€ and 2 to 3.3 years respectively. The novel layout of the energy-efficient rubber dryer, and its energy performance are illustrated.

One Cool Guy: Scientific Contributions of John Hayward, Cold Water Pioneer.

John Hayward, PhD (1937-2012), was an early and significant contributor to the understanding of cold water immersion physiology and survival. This article summarizes his work on the 50th anniversary of his first publication in this area. He described areas of high heat loss and emphasized the importance of protecting these areas during cold exposure using the Heat Escape Lessening Posture (HELP) and the potential for heat donation to these areas during rewarming. He described several factors that affect the rate of core cooling, including body composition, behavior (swimming increases cooling whereas the HELP position decreases cooling), wet and wind, and thermal protective garments (dry suits offered much more protection than wet suits). Hayward determined breath-hold duration in children as young as 4 y and had his own heart catheterized for 3 d to complete 3 hypothermia rewarming trials. His work provided early understanding of the cold shock response and ways to mitigate its threat to survival. Hayward provided valuable contributions to prediction models for heat production, heat loss, and core cooling rates in cold water. He also developed a human model for severe hypothermia and patented the UVic Thermofloat Jacket. Finally, as evidence of his stature in the cold physiology community, Hayward was a coauthor of the initial State of Alaska guidelines for the treatment of hypothermia. John Hayward was truly a cold water pioneer.

Extremity cooling during an arctic diving training exercise

ABSTRACT A field study was conducted to examine the vulnerability of military divers to non-freezing cold injury (NFCI) during Arctic ice-diving operations. Participants were instrumented with temperature sensors on the back of their hands and on the bottom of their big toe for each dive to measure cooling of their extremities. While NFCI was not diagnosed in any of the participants during this field study, the data indicate that the feet were particularly vulnerable during the dives given that they were mostly in a temperature zone that could cause pain and performance decrements. The data also show that for short term dives, the dry and wet suits with wet gloves in both configurations were thermally more comfortable for the hands than the dry suit with dry glove configuration; however, the latter would be more protective against potential NFCI during longer dives. Features such as hydrostatic pressure and repetitive diving that are unique to diving but not previously considered as risk factors for NFCI are examined herein and warrant deeper investigation given that symptoms of NFCI might be mistaken as decompression sickness.

Aaru

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PO-1716 Neoprene wet suit hood bolus in total scalp helical tomotherapy: does it work?

PO-1716 Neoprene wet suit hood bolus in total scalp helical tomotherapy: does it work?

Thermoregulatory responses during prolonged swimming with a Wetsuit at 25 °C

ABSTRACT The aim of this study was to investigate the effect of prolonged steady state swimming with a wetsuit, on thermoregulatory and behavioural responses, in water of 25°C. Ten male swimmers participated in two 75-min swim trials, in one wearing a neoprene wetsuit (WS), and the other a conventional swimsuit (SS). The swimming intensity was controlled at 70% of swimmers’ critical velocity (CV). Core (Tcore) and skin (Tsk) temperature, heart rate (HR), and behavioural modulators, were measured before, during and after swimming. A 2-way ANOVA for repeated measures with aFisher’s 2SD test was used for multiple comparisons and a paired t-test with a Tukey post hoc analysis for pre and post measurements at p< 0.05. The results demonstrated an interaction of Tcore (p = 0.039), between time in the water and type of garment worn. Tcore with the WS initially increased until the 45th min and plateaued, while with the SS was continuously decreasing. HR was lower during swimming with the WS and higher with the SS. Thermal sensation and thermal comfort, were more favourable with the WS (p < 0.05). Thus, WS use during prolonged swimming, helped maintain Tcore levels, and improved thermal perceptions, at 25 °C.

Багатофакторна модель підйому водолазом-сапером вибухонебезпечного предмету

The use of experimental research planning methods has shown that to obtain a multifactor model of lifting an explosive object by a sapper diver from a depth that will take into account both the impact, in case nonlinear, selected parameters and the effects of interaction between them, it is advisable to conduct a multifactorial experiment 3x3x2. Statistical indicators of the time of lifting an explosive object in accordance with such a plan can be obtained using the method of direct expert assessments. As a result, a multifactor model of lifting an explosive object by divers in the form of a three-factor square polynomial was obtained, the coefficients of which establish a quantitative relationship between the level of training of personnel, external conditions in which he works and lifeguards. Field experiments confirmed the reliability of the developed mathematical model with a significance level of α = 0,05. It is shown that when de-veloping operational and technical recommendations, divers need to take into account both the type of diving suit and the effects of the interaction between the level of training of personnel and the conditions in which they work. At the same time, it is possible to ignore the effects of the interaction of the conditions of lifting an explosive object with the suit in which the sapper divers work, as well as the quadratic effect of using a dry or wet suit. It should be expected that in the case of lifting an explosive device, the level of preparedness will be more pronounced in divers-sappers with a primary level, as well as the fact that for them to reduce the effectiveness of underwater demining will be affected by poor external working conditions. During further research, increased attention should be paid to the preparation of diver sappers to work in difficult conditions and to the planning of operational activities of a specialized pyrotechnic unit, as well as the use of the latest technical means of underwater demining.

Green tobacco sickness among tobacco harvesters: A review of the literature

Green tobacco sickness (GTS) is an occupational illness that affects tobacco harvesters. It is a type of acute nicotine intoxication caused by nicotine absorption through the epidermis of a moist green tobacco plant. The purpose of this study was to systematically review the existing literature on the green tobacco sickness and its health impacts on tobacco harvesters. A standard literature search was performed using multiple electronic databases like PubMed, PubMed Central, Cochrane Library, Campbell systematic review Embase, Google Scholar and Scopus for studies published on green tobacco sickness from 2000 to 2020. A total of 11 studies with a total population of 6,253 were reviewed. The prevalence of green tobacco sickness among tobacco harvesters ranged from 6.6% to 56.9%. Exposure to Sunlight, use of pesticides, Stalk removal of tobacco leaves, gender of the farmer, smoking, skin rash, wearing a wet suit, process of curing tobacco leaves, and watering tobacco plants, task, topping, barning and working in wet clothing were some of the risk factors reported by authors. Green tobacco sickness was shown to be common in the study population, indicating that a significant regulatory effort is needed to address the potential dangers of GTS.

Factors Affecting Organizational Success: A Case Of Body Glove

This paper aims to investigate how Body Glove, an outdoor water sports brand started in the United States, drives organizational success. This brand specializes in wet suits. Body Glove has good product quality and continues to develop its product via research and development to meets customers’ expectations. Their passion for water sports led them to create the first wet suit to help fight those cold California waters. The price offered by Body Glove is affordable and worth it with its quality. Body Glove also provides online shopping that can ease customers to enjoy online shopping. We will test the hypotheses using survey. This paper contributes to understanding of how driving factors results in organizational success

Evaluating the thermal protection provided by a 2‒3 mm wet suit during fin diving in shallow water with a temperature of 16‒20°C.

The purpose of the study was to evaluate the thermal protection provided by a 2-3 mm surfing wet suit during at least two hours of fin diving in shallow water with a temperature of 16-20°C. We examined the effect of wearing the suit while diving in cold water on cognitive performance, muscle strength, and hand motor function. Subjects were six male well-trained rebreather divers, 19-23 years old, acclimatised to cold. They attended the laboratory on three separate occasions, when we conducted the experiment at one of three temperatures, 16, 18, and 20°C. Core temperature (gastrointestinal system), skin temperature, oxygen consumption, and cold perception were evaluated during the test. Before and immediately after the dives, subjects performed a series of cognitive, manual dexterity, and muscle strength tests. Core temperature decreased by 0.35-0.81°C over the two hours at all three water temperatures. No subject reached a core temperature below 35°C. The decrease in upper body skin temperature during the two hour dive ranged between 5.97 and 8.41°C (P < 0.05). Two hours diving in 16-20°C water resulted in a significant increase in the time taken to perform the task of unlinking and reassembling four shackles (∼30% longer, P < 0.05). No effect was found on the cognitive or muscle strength tests. A 2-3 mm wet suit provides adequate thermal protection in trained and cold-acclimatised young males engaged in active diving in shallow water with a temperature of 16°C and above.

A study of the improvement of foam material sealing technology for wetsuits

The purpose of this study is to propose the most suitable sewing method to produce wetsuits using neoprene fabric. To construct a sewing method sample using neoprene fabric, the samples were prepared using two thicknesses (1.5 t and 3 t) of neoprene fabric. Sewing techniques comprised 10 different methods. The respective seam strengths (KSK 0530) and water resistance (KSK ISO 811) of each sample were measured. The results from the tests conducted using 10 sewing methods revealed that the seam strength of 466.7 N was the highest in the prototype constructed using zigzag and flatlock stitches on 1.5 t. The other samples had seam strengths of approximately 400 N, except for that sewn with straight stitch (113.3 N). For 3 t, the sample sewn using zigzag and flatlock stitches with seam sealing (653.3 N) had the highest strength, and the remaining samples had seam strengths of approximately 630 N, except the sample sewn with straight stitch (164.6 N). Significant factors affecting the seam strength were fabric thickness and the sewing method. Meanwhile, glue and blind stitch with seam sealing had the highest value for water resistance: 414.4 mH2O for 1.5 t and 987.6 mH2O for 3 t. The lowest values were revealed in samples sewn with zigzag and flatlock stitch 14.4 mH2O for 1.5 t and overlock stitch 13.3 mH2O for 3 t. Significant factors affecting water resistance were whether seam sealing was attached and the sewing method used. The expected result of this study, which tests the properties of two neoprene fabric thicknesses with 10 sewing methods, is the suggestion of the most appropriate sewing method for use in the production of a wet suit.

Hell’s Bells: Notes on Tone

Hell’s Bells: Notes on Tone Mary Ruefle (bio) In early spring, in Croatia, old men and young men get up in the dark and get dressed in sheepskins, they don huge sheepskin masks and around their waists they tie giant sheep-bells. They proceed to parade through remote villages, making a racket. They are the Halubian bell-ringers, and their job is to ward off the evil spirits of winter so that the benevolent spirits of spring can arrive safely. This is their warm welcome, a ritual no less bizarre than writing a poem. Here we are in early spring. We have survived the winter. Some of us; those who have not are not, strictly speaking, here. Sooner than you think, it will be summer. Last summer I went back to a state park I had not visited in twenty-five years; I wanted, suddenly, to swim in the lake which is its centerpiece. And so I went, but left after fifteen minutes, without swimming, though I sat on a towel in the grass staring at the lake. Something was missing. It took me those fifteen minutes to figure it out — the old concession shack was no more, it had been shut down. And though I loved the sound of splashing water and airborne shouts, what I loved most [End Page 206] was the sound of the little bell that rang every time a kid went into or came out of the concession shack, opening or closing its screen door. Kids in wet suits who went in to buy Creamsicles and came out licking them as the orange and white goo dripped. The bell! The bell! I missed the constant sound of that dinky bell, and my heart was broken. The sound of that bell was gone forever. You see, I am not really interested in tone; I am interested in bells. Here’s something intriguing: when I asked poets under the age of fifty what tone was (in a poem) they all said more or less it was the contextual inflection or attitude that helped determine meaning in a poem. When I asked poets over the age of fifty, they all said more or less that tone was a presence that was helplessly itself. I am not pitting these groups against each other, for both answers are relevant and meaningful, but being over fifty I do gravitate toward the helpless presence of a voice. At the same time, there are instances of the other I find riveting. On the day of the total eclipse of the sun in August 2017, a group of people in Oregon standing under the direct path of the solar event cheered and shouted during the minutes of totality. Cheered and shouted as if it were the stroke of midnight on New Year’s Eve. A group of people in Idaho, witnessing the same event, went dead silent in unison. I take these as two tones in response to the identical subject. The event was the subject, and the response was the tone. What would you have done? To which group do you belong? One older poet I asked about tone said, “Tone? My inner ear senses it, it’s just a feeling. There are a lot of writers I can’t read because I don’t yet have a sense of their tone. It’s not a criticism, it just means I don’t have the immediate affinity I have with someone like, say, Vallejo. And he’s one among a hundred.” [End Page 207] What is Vallejo’s tone, I asked, and he said, “I’ve never tried to put it into words. It’s in my ear. I used to say about Vallejo that I felt the poem was handed to me on a silver platter — it felt, sounded like a gift. With other writers, I sometimes feel like I am supposed to give them something. I know I’m not, but it can feel that way.” Does that have to do with the poet, or with you, I asked. “It’s a two-way street. An example for me is Borges. For some reason, I’m not there yet...

Aquatic cycling-What do we know? A scoping review on head-out aquatic cycling.

Over the past few years, aquatic cycling has become a trending fitness activity. However, the literature has not been reviewed exhaustively. Therefore, using scoping review methodology, the aim of this review was to explore the current state of the literature concerning aquatic cycling. This study specifically focused on study designs, populations and outcomes. A comprehensive search of seven databases (PubMed, MEDLINE, Cinahl, Embase, PEDro,Web of Science, WorldCat) was conducted up to 30th September 2016. GoogleScholar, World Cat, ResearchGate, specific aquatic therapy websites and aquatic therapy journals were searched to identify additional literature. Full-text publications in English, German or Dutch were included. Studies were included when the intervention involved head-out cycling carried out in 10° to 35° Celsius water. Exclusion criteria were the use of wet suits or confounding interventions that would affect participants’ homeostasis. 63 articles were included and the study parameters of these studies were summarized. Using three grouping themes, included studies were categorised as 1) single session tests comparing aquatic versus land cycling, or 2) aquatic cycling only sessions investigating different exercise conditions and 3) aquatic cycling intervention programmes. Although the experimental conditions differed noticeably across the studies, shared characteristics were identified. Cardiovascular parameters were investigated by many of the studies with the results suggesting that the cardiac demand of aquatic cycling seems similar to land-based cycling. Only six studies evaluated the effect of aquatic cycling interventions. Therefore, future research should investigate the effects of aquatic cycling interventions, preferably in individuals that are expected to gain health benefits from aquatic cycling. Moreover, this comprehensive outline of available literature could serve as a starting point for systematic reviews or clinical studies on the effects of aquatic cycling on the cardiovascular responses.

Finger cold-induced vasodilation of older Korean female divers, haenyeo: effects of chronic cold exposure and aging.

The aim of the present study was to evaluate the local cold tolerance of older Korean female divers, haenyeo (N=22) in terms of cold acclimatization and ageing. As control groups, older non-diving females (N=25) and young females from a rural area (N=15) and an urban area (N=51) participated in this study. To evaluate local cold tolerance, finger cold-induced vasodilation (CIVD) during finger immersion of 4°C water was examined. As a result, older haenyeos showed greater minimum finger temperature and recovery finger temperature than older non-diving females (P<0.05), but similar responses in onset time, peak time, maximum finger temperature, frequency of CIVD, heart rate, blood pressure, and thermal and pain sensations as those of older non-diving females. Another novel finding was that young urban females showed more vulnerable responses to local cold in CIVD variables and subjective sensations when compared to older females, whereas young rural females had the most excellent cold tolerance in terms of maximum temperature and frequency of CIVD among the four groups (P<0.05). The present results imply that older haenyeos still retain cold acclimatized features on the periphery even though they changed their cotton diving suits to wet suits in the early 1980s. However, cardiovascular responses and subjective sensations to cold reflect aging effects. In addition, we suggest that young people who have been adapted to highly insulated clothing and indoor heating systems in winter should be distinguished from young people who were exposed to less modern conveniences when compared to the aged in terms of cold tolerance.

Cardiovascular Mechanisms of Extravascular Lung Water Accumulation in Divers

This study assessed the relation between altered cardiac function and the development of interstitial pulmonary edema in scuba divers. Fifteen healthy men performed a 30-minute scuba dive in open sea. They were instructed to fin for 30minutes and were wearing wet suits. Before and immediately after immersion, cardiac indexes and extravascular lung water were measured using echocardiography and lung ultrasound, respectively. The mean ultrasound lung comet score increased from 0 to 4.6 ± 3.4. The diameter of the inferior caval vein increased by 47 ± 5.2%, systolic pulmonary artery pressure by 105 ± 8.6%, left atrial volume by 18.0 ± 3.3%, and left ventricle end-diastolic volume by 10 ± 2.4% suggesting that both right and left ventricular (LV) filling pressures were elevated. Doppler studies showed an increased mitral E peak (+2.5 ± 0.3%) and E/A ratio (+22.5 ± 3.4%) with a decreased mitral A peak (-16.4 ± 2.7%), E peak deceleration time (-14.5 ± 2.4%) consistent with rapid early LV filling but without a change in LV stroke volume. There was an increase in right/left ventricle diameter ratio (+33.6 ± 4.8%) suggesting a relative increase in right-sided heart output compared with the left. Furthermore, the lung comet score correlated significantly with inferior caval vein diameter, systolic pulmonary artery pressure, right/left ventricle diameter ratio, and E-wave deceleration time. In conclusion, the altered right/left heart stroke volume balance could play an essential role in the development of immersion pulmonary edema. Our findings have important implications for the pathogenesis of cardiogenic pulmonary edema.

A History of African Americans on the Water and by the Shore: Whitewashed and Recovered

PROFILING THE LIVES OF BLACK SURFERS in California, the Pacific islands, Florida, and the Caribbean, the documentary film White Wash tells an important story of black cultural formation and expression in modern America, and challenges some of the most widely held assumptions about race and identity in popular culture today. Beautifully narrated by Ben Harper and Tariq “Black Thought” Trotter of The Roots, who also scored the film, White Wash is a testament to the power of leisure and sports to both challenge and transcend racial constructs. It takes as its subject one of the most quintessentially “white” sports in America today—surfing—and reveals its fundamentally multicultural origins and development, and its continued relevance to segments of black America today. More than simply a recovery of a previously neglected chapter in black life and history, White Wash addresses the question of how certain sports and activities came to be labeled “white” or “black” in the public’s mind, and how the racialization of sports shaped and informed the meaning of racial difference for both whites and people of color in the Americas. White Wash is a sweeping and engrossing tale of human perseverance and cultural resiliency, set along the edges of the continent and the islands of the Atlantic and Pacific, where, for centuries, people of diverse backgrounds came into contact and where the creolization of cultures began. Not coincidentally, the beach has also been the place where the “color line” was drawn and enforced with great vigilance, where the project of defining race and segregating “races” was most urgent, and where the erasure of African contributions to the making of American cultures was most thorough. Thus, for most Americans today, beach culture is synonymous with white culture. Visually, surfing conjures images of blondehaired Caucasians in wet suits, and sonically, brings to mind musicians such as The Beach Boys, Dick Dale, and songs such as “Pipeline” and “Wipe Out.” The film shows how popular understandings of what constitutes beach culture in America today is the product of a history of exclusion, backed by fear and the constant threat of

Assessing thermal resistance of wet suits on human subjects during aquatic activity by a heat flux method

Thermal protection of wet suits for aquatic sport (surfing, snorkelling, outdoor swimming) is impacted by design (stretch and fit, type of seams, design of openings) as water coming in and flushing between the skin and suit dramatically increases body heat loss. We developed a test protocol for measuring thermal resistance of a suit on a human subject while performing an activity in water. Six surf suits were compared and two swimming suits differing by thickness and stretch of neoprene, type of seams and neck design.

Green Tobacco Sickness among Thai Traditional Tobacco Farmers, Thailand.

Background: Traditional Thai tobacco (Nicotiana abacus L.) is known as a non-Virginia type whose mature leaf contains three to four times more nicotine than that of a Virginia type. As such, the process of Thai traditional tobacco production may lead to adverse health effects such as green tobacco sickness (GTS). Objective: To investigate the prevalence of GTS and risk factors related to GTS among Thai traditional tobacco farmers in Nan province, northern Thailand. Methods: 473 Thai traditional tobacco farmers from rural areas in Nan province were randomly selected and interviewed in person by means of questionnaires and environmental survey. Statistical analyses were used to identify potential risk factors for GTS. Results: The prevalence of GTS was 22.6% (95% CI 19.1% to 26.6%). Multivariate analysis showed various risk factors associated with GTS including gender of the farmer (ORadj 0.44, 95% CI 0.26 to 0.73), smoking (ORadj 4.36, 95% CI 1.41 to 13.47), skin rash (ORadj 0.36, 95% CI 0.19 to 0.68), wearing a wet suit (ORadj 1.91, 95% CI 1.12 to 3.23), process of curing tobacco leaves (ORadj 0.06, 95% CI 0.02 to 0.16), and watering tobacco plants (ORadj 0.42, 95% CI 0.25 to 0.72). Conclusion: The process of traditional Thai tobacco production can result in increased dermal exposure and can be considered a major risk factor for GTS. Body soaking during watering may further increase adverse health effects related to GTS.

Triathlon Research

PURPOSE: To investigate if wearing a triathlon wetsuit influences rate of oxygen consumption (VO2), heart rate (HR), rating of perceived exertion (RPE), preferred running speed (PRS), and/or stride frequency (SF). METHODS: Twenty subjects (male n=10, 33.8±8.18 years, 1.78±0.05 m, 79.4±3.75 kg; female n=10, 27.9 ±8.53 years, 1.65±0.06 m, 63.6±5.98 kg) completed 5 minutes of running on the treadmill during four conditions: no wetsuit (NWS), carrying wetsuit (CWS), wetsuit worn fully on (WSfull), wetsuit worn halfway down (WShalf). Prior to testing, PRStest was determined for NWS and used for all test conditions. Before testing each condition, PRScond was determined for that condition - but all testing was done using the PRStest during NWS. During each running condition, RPE and SF was collected at the beginning, middle, and end of the 5-min time interval while VO2 and HR data collected throughout the 5-mins at 15s intervals. VO2 and HR data were averaged over the last 3-minutes while RPE and SF were averaged across each condition. Each dependent variable was analyzed using a repeated measures ANOVA with simple effects post hoc testing comparing NWS to each of the other conditions (α=0.05). RESULTS: SF, HR, RPE, or PRScond were not different between conditions (p>0.05). VO2 was different between conditions (p>0.05). CONCLUSIONS: HR, PRScond, SF, and RPE were not affected by the way the wet suit was carried or worn. However, running while carrying or wearing the wetsuit did tend to increase VO2 by about 6-8%. Based upon this study, it seems that triathletes can estimate the energetic cost of T1 by about 6-8% more than running with no wet suit.

에르고노믹 패션 디자인연구 - 바디컨셔스 액티브 스포츠웨어를 중심으로 -

The meaning of this research is to make recognition for necessity of ergonomic fashion design research. And the purpose is to provide the guidelines for ergonomic fashion product development. For this, literature research and analysis of empirical illustration of product design indicating ergonomics characteristic are implemented. Among the body-conscious active sportswear, cycle wear, swim suit, and skin scuba wet suit were selected and analyzed. Then they were explained according to the ergonomics characteristics arranged previously. Lastly, the features of ergonomic fashion design were arranged by composition elements of the clothing such as pattern, sewing, material and detail. The characteristics of ergonomic design derived from literature and advanced researches are efficiency, usability, functionality and safety. Through research and analysis, the characteristics of ergonomic fashion design are as followings. In pattern, it is related to the 3D structure division pattern, the reduction pattern design, the closing & opening part design for easy detachment, the receipt and the changeable design. In sewing, it is related to the use of latest sewing techniques and the finish using silicon or rubber band. In material, it is related to the use of high performance fabrics and the proper arrangement of these. In detail, it is related to the convenient detail, the storage detail, the adjustable detail, and the body protection detail.