Safety of a continuous glucose monitoring device during hyperbaric exposure.

Background: Hyperbaric oxygen therapy has been demonstrated to lower blood glucose levels in patients with diabetes. Continuous glucose monitoring (CGM) allows glucose monitoring in real time. Battery-operated CGM transmitters have yet to be formally tested and given safety approval for use in a hyperbaric environment. Materials and Methods: We evaluated and tested commercially available Dexcom® G6 CGM transmitters under hyperbaric conditions. Each transmitter contains a 3V, 130-mAh (0.39 Wh) lithium manganese dioxide battery (IEC CR1632) and circuit board that are fully encapsulated in epoxy. Each transmitter is pressurized to 90 pounds per square inch (psi) in an autoclave at 40°C for up to 72 hours during manufacturing to ensure that all enclosed air spaces are eliminated from the epoxy. We compared the CGM components against section 14.2.9.3.17.5 of the 2018 National Fire Protection Association 99 (NFPA 99) Health Care Facilities Code requirements. Six CGM transmitters attached to estimated glucose value generators (EGVGs) underwent 11 pressurization cycles to 45 feet of seawater (fsw). All transmitters were returned to the manufacturer to assess post-exposure structural integrity. G6 sensors, which contain no electrical components or compressible air spaces, do not pose a risk in the hyperbaric environment. Results: There was no observed change in preset EGVG readings during hyperbaric exposures. Post-exposure testing revealed no structural compromise after repeated hyperbaric exposures. Conclusions: The CGM transmitter meets section 14.2.9.3.17.5 of the 2018 NFPA 99 requirements for battery-operated devices allowed for use in a hyperbaric environment. This analysis revealed no significant safety concerns with subjecting Dexcom G6 CGM transmitters to hyperbaric environments.

Natural antioxidant functionalization for fabricating ambient-stable black phosphorus nanosheets toward enhancing flame retardancy and toxic gases suppression of polyurethane.

Herein, as a natural antioxidant, tannin (TA) is firstly used to functionalize black phosphorous (BP) nanosheets to improve the ambient stability and toxic suppression, thus decreasing the fire hazards of polymer materials. Compared to pure BP nanosheets, higher temperature for thermal oxidation decomposition is achieved for TA-BP nanosheets, directly confirming the ambient stability of TA-BP nanosheets. Meanwhile, from high resolution TEM and XPS results, TA-BP nanosheets after being exposed at air for 10 days present well-organized crystal structure and low POx bonds content. Cone calorimeter results illustrate that the incorporation of 2.0 wt% TA-BP nanosheets significantly decreases the peak value of heat release rate (-56.5 %), total heat release (-43.0 %), CO2 concentration (-57.3 %) of TPU composite. Meanwhile, with addition of low to 1.5 wt%, the release of highly-toxic CO gas is significantly suppressed, confirmed by lower peak value (0.52 mg/m3) and decreased total release amount (-55.1 %). The obviously enlarged tensile strength (36.7 MPa) and desirable elongation at break (622 %) are also observed. This strategy not only firstly adopts bio-based antioxidant to impart excellent environmental stability for BP nanosheets, but also promotes the promising potentials of BP nanosheets in the fire safety application of polymer composites.

Community owned solutions for fire management in tropical ecosystems: case studies from Indigenous communities of South America.

Fire plays an increasingly significant role in tropical forest and savanna ecosystems, contributing to greenhouse gas emissions and impacting on biodiversity. Emerging research shows the potential role of Indigenous land-use practices for controlling deforestation and reducing CO2 emissions. Analysis of satellite imagery suggests that Indigenous lands have the lowest incidence of wildfires, significantly contributing to maintaining carbon stocks and enhancing biodiversity. Yet acknowledgement of Indigenous peoples' role in fire management and control is limited, and in many cases dismissed, especially in policy-making circles. In this paper, we review existing data on Indigenous fire management and impact, focusing on examples from tropical forest and savanna ecosystems in Venezuela, Brazil and Guyana. We highlight how the complexities of community owned solutions for fire management are being lost as well as undermined by continued efforts on fire suppression and firefighting, and emerging approaches to incorporate Indigenous fire management into market- and incentive-based mechanisms for climate change mitigation. Our aim is to build a case for supporting Indigenous fire practices within all scales of decision-making by strengthening Indigenous knowledge systems to ensure more effective and sustainable fire management.This article is part of the themed issue 'The interaction of fire and mankind'.

Fire risk reduction through a community-based risk assessment: reflections from Makola Market, Accra, Ghana.

This paper explores the level of vulnerability to the hazard of fire that exists in Makola Market in Accra, Ghana, and assesses how this threat can be reduced through a community-based risk assessment. It examines the perceptions of both market-stall occupants and primary stakeholders regarding the hazard of fire, and analyses the availability of local assets (coping strategies) with which to address the challenge. Through an evaluation of past instances of fire, as well as in-depth key stakeholder interviews, field visits, and observations, the study produces a detailed hazard map of the market. It goes on to recommend that policymakers consider short-to-long-term interventions to reduce the degree of risk. By foregrounding the essence of holistic and integrated planning, the paper calls for the incorporation of disaster mitigation measures in the overall urban planning process and for the strict enforcement of relevant building and fire safety codes by responsible public agencies.

Incêndio no centro cirúrgico / Fire in the surgical center / Incendio en el quirófano

JUSTIFICATIVA E OBJETIVOS: A existência de um ambiente rico em oxigênio, material combustível em abundância e a utilização de aparelhos capazes de fornecerem ignição transformam a sala cirúrgica em um ambiente de risco para a ocorrência de incêndios. Apesar de rara, trata-se de uma complicação potencialmente grave e na maioria das vezes evitável. Relatamos um caso de incêndio no campo cirúrgico durante uma cirurgia de blefaroplastia em que foi suplementado oxigênio por meio de cateter nasal. RELATO DO CASO: Paciente de 52 anos, sexo feminino, sem comorbidades, admitida para realização de blefaroplastia bilateral. Após monitorização e venóclise, procedeu-se à sedação endovenosa com oferta de oxigênio suplementar por meio de cateter tipo óculos, com fluxo de 4 L.min-1, seguida de anestesia local das pálpebras. Durante o ato cirúrgico, a utilização do bisturi elétrico ocasionou combustão dos campos cirúrgicos e queimaduras na face da paciente. CONCLUSÕES: O anestesiologista desempenha papel fundamental na prevenção de incêndio na sala cirúrgica, reconhecendo possíveis fontes de ignição e administrando de forma racional o oxigênio, principalmente com sistemas abertos. O primeiro passo para a prevenção deve ser a lembrança constante da possibilidade de incêndio.

BACKGROUND AND OBJECTIVES: There are several factors in operating rooms that increase the risk of fire. Besides being an oxygen-enriched environment, it contains combustible materials and equipment with available ignition sources. Although fires in operating rooms are a relatively rare event, the consequences are potentially serious and mostly avoidable. We present a case report of a fire occurring in the surgical drape during a blepharoplasty in which oxygen was supplemented by nasal catheter. CASE REPORT: Female patient, 52-years old, without comorbidities, admitted to hospital for a bilateral blepharoplasty. After monitoring and venoclysis, the patient underwent intravenous sedation and additional oxygen given via spectacle-type catheter at a flow rate of 4 L.min-1, followed by local anesthesia in the eyelids. During surgery, the use of electric scalpel provoked combustion in the surgical drapes and burns on the patient's face. CONCLUSIONS: Anesthesiologists play an important role preventing fire in operating rooms, as they can recognize possible ignition sources and rationally administer the oxygen, especially in open systems. The first step toward prevention is to be constantly aware of potential fire.

JUSTIFICATIVA Y OBJETIVOS: La existencia de un ambiente rico en oxígeno, material combustible en abundancia, y la utilización de aparatos capaces de realizar la ignición, transforma el quirófano en un ambiente de riesgo para el conato de incendios. A pesar de ser una complicación rara, es potencialmente grave y en la mayoría de los casos se puede evitar. Relatamos aquí un caso de incendio en el ambiente quirúrgico durante una cirugía de blefaroplastia en que fue suministrado oxígeno por medio de un catéter nasal. RELATO DEL CASO: Paciente de 52 años, del sexo femenino, sin comorbilidades, admitido para la realización de blefaroplastia bilateral. Posteriormente a la monitorización y a la venoclisis, se procedió a la sedación endovenosa con oferta de oxígeno suplementario por medio de un catéter tipo gafas con flujo de 4 L.min-1, seguida de anestesia local en los párpados. Durante la operación, la utilización del bisturí eléctrico creó una combustión de los campos quirúrgicos produciendo quemaduras en la cara de la paciente. CONCLUSIONES: El anestesiólogo desempeña un rol fundamental en la prevención del incendio en el quirófano, reconociendo posibles fuentes de ignición y administrando de forma racional el oxígeno, principalmente con sistemas abiertos. El primer paso para su prevención es estar siempre alertas sobre la posibilidad de que se pueda producir un incendio.

Flammability of topical preparations and surgical dressings in cutaneous and laser surgery: a controlled simulation study.

BACKGROUND: Surgical fires are a rare, but serious complication of dermatologic procedures involving electrosurgical and laser devices. Given the lack of data regarding basic fire safety principles, many dermatologists remain unaware of this potential risk. OBJECTIVE: We evaluated the flammability of topical preparations and surgical drapes commonly encountered in the immediate operative field during cutaneous and laser surgery. METHODS: Surgical dressings, drapes, and pork belly skin were examined for fire risk upon exposure to isopropyl alcohol, chlorhexidine gluconate, and aluminum chloride under dry, saturated, and damp conditions. Both electrosurgery and a carbon-dioxide laser were used as ignition sources. RESULTS: At least some char was observed in 86 of 126 simulated conditions (68%). Flames occurred in 2 test conditions: dry underpad drapes and cotton balls exposed to the carbon-dioxide laser. In general, drapes and dressings dampened or saturated with isopropyl alcohol failed to ignite with electrofulguration or electrodessication, although sparks and moderate char developed on pork belly skin and the underpad drape. Materials dampened or saturated with chlorhexidine gluconate, which contains isopropyl alcohol, generated less smoke and char compared with materials exposed to aluminum chloride, which does not contain alcohol. LIMITATIONS: Future studies may assess the flammability of materials in the setting of oxygen supplementation. CONCLUSION: In common cutaneous surgical environments, electrosurgery or ablative laser may lead to char and rarely to fire. Char may be seen in up to two thirds of simulated conditions, and in a minute proportion of conditions, fire is observed.

Identification of fireproofing zones in Oil&Gas facilities by a risk-based procedure.

Fire is among the more dangerous accident scenarios that may affect the process and chemical industry. Beside the immediate and direct harm to workers and population, fire may also cause damages to structures, which may trigger escalation resulting in severe secondary scenarios. Fireproofing is usually applied to improve the capacity of structures to maintain their integrity during a fire. Past accidents evidenced that the available standards for fireproofing application in onshore chemical and process plants do not consider all the fire scenarios that may cause structural damage. In the present study a methodology was developed for the identification of the zones where fireproofing should be applied. The effect of both pool fires and jet fires was accounted. Simplified criteria, based on radiative heat intensity, were provided for the identification of the fire protection zones. A risk-based procedure was proposed for the selection of significant reference release scenarios to be used in the evaluation of worst credible fire consequences.

The development of an inherent safety approach to the prevention of domino accidents.

The severity of industrial accidents in which a domino effect takes place is well known in the chemical and process industry. The application of an inherent safety approach for the prevention of escalation events leading to domino accidents was explored in the present study. Reference primary scenarios were analyzed and escalation vectors were defined. Inherent safety distances were defined and proposed as a metric to express the intensity of the escalation vectors. Simple rules of thumb were presented for a preliminary screening of these distances. Swift reference indices for layout screening with respect to escalation hazard were also defined. Two case studies derived from existing layouts of oil refineries were selected to understand the potentialities coming from the application in the methodology. The results evidenced that the approach allows a first comparative assessment of the actual domino hazard in a layout, and the identification of critical primary units with respect to escalation events. The methodology developed also represents a useful screening tool to identify were to dedicate major efforts in the design of add-on measures, optimizing conventional passive and active measures for the prevention of severe domino accidents.

Decision process to assess medical equipment for hyperbaric use.

There are very few items of medical equipment specifically designed for hyperbaric use; and little information is available about medical equipment already tested for hyperbaric use. Hyperbaricists are usually left to their own devices in making a determination about the safe and effective use of standard medical equipment in the hyperbaric setting. This article proposes a logical and systematic process to arrive at this determination. The process involves seven steps beginning with a need assessment and ending with endorsement by appropriate individuals. The discussion of decision steps includes identifying risk elements, compliance with safety standards, testing, and documentation.

Risk reduction in road and rail LPG transportation by passive fire protection.

The potential reduction of risk in LPG (Liquefied Petroleum Gas) road transport due to the adoption of passive fire protections was investigated. Experimental data available for small scale vessels fully engulfed by a fire were extended to real scale road and rail tankers through a finite elements model. The results of mathematical simulations of real scale fire engulfment scenarios that may follow accidents involving LPG tankers proved the effectiveness of the thermal protections in preventing the "fired" BLEVE (Boiling Liquid Expanding Vapour Explosion) scenario. The presence of a thermal coating greatly increases the "time to failure", providing a time lapse that in the European experience may be considered sufficient to allow the start of effective mitigation actions by fire brigades. The results obtained were used to calculate the expected reduction of individual and societal risk due to LPG transportation in real case scenarios. The analysis confirmed that the introduction of passive fire protections turns out in a significant reduction of risk, up to an order of magnitude in the case of individual risk and of about 50% if the expectation value is considered. Thus, the adoption of passive fire protections, not compulsory in European regulations, may be an effective technical measure for risk reduction, and may contribute to achieve the control of "major accidents hazards" cited by the European legislation.

Smoke alarms for sleeping adults who are hard-of-hearing: comparison of auditory, visual, and tactile signals.

OBJECTIVES: People who are hard-of-hearing may rely on auditory, visual, or tactile alarms in a fire emergency, and US standards require strobe lights in hotel bedrooms to provide emergency notification for people with hearing loss. This is the first study to compare the waking effectiveness of a variety of auditory (beeps), tactile (bed and pillow shakers), and visual (strobe lights) signals at a range of intensities. DESIGN: Three auditory signals, a bed shaker, a pillow shaker, and strobe lights were presented to 38 adults (aged 18 to 80 yr) with mild to moderately severe hearing loss of 25 to 70 dB (in both ears), during slow-wave sleep (deep sleep). Two of the auditory signals were selected on the basis that they had the lowest auditory thresholds when awake (from a range of eight signals). The third auditory signal was the current 3100-Hz smoke alarm. All auditory signals were tested below, at, and above the decibel level prescribed by the applicable standard for bedrooms (75 dBA). In the case of bed and pillow shakers intensities below, at, and above the level as purchased were tested. For strobe lights three levels were used, all of which were above the applicable standard. The intensity level at which participants awoke was identified by electroencephalograph monitoring. RESULTS: The most effective signal was a 520-Hz square wave auditory signal, waking 92% at 75 dBA, compared with 56% waking to the 75 dBA high-pitched alarm. Bed and pillow shakers awoke 80 to 84% at the intensity level as purchased. The strobe lights awoke only 27% at an intensity above the US standard. Nonparametric analyses confirmed that the 520-Hz square wave signal was significantly more effective than the current smoke alarm and the strobe lights in waking this population. CONCLUSIONS: A low-frequency square wave signal has now been found to be significantly more effective than all tested alternatives in a number of populations (hard-of-hearing, children, older adults, young adults, alcohol impaired) and should be adopted across the whole population as the normal smoke alarm signal. Strobe lights, even at high intensities, are ineffective in reliably waking people with mild to moderate hearing loss.

The selection of skin care products for use in hyperbaric chamber may depend on flammability acceptability indices score.

PURPOSE: Current protocols call for stopping adjunctive skin care treatments during hyperbaric oxygen therapy (HBOT) because the hyperbaric environment is considered unsafe for skin care products. The elevated oxygen fraction and the increased pressure in the hyperbaric chamber dramatically increase the flammability potential of materials, leading to the need for rigorous standards to prevent flame ignition. A scientific method of evaluating the flammability risks associated with skin care products would be helpful. Several skin care products were tested, using established industrial techniques for determining flammability potential with some modification. The information obtained from these tests can help clinicians make more rational decisions about which topical products can be used safely on patients undergoing HBOT. METHODS AND MATERIALS: Wendell Hull & Associates conducted independent studies, comparing the oxygen compatibility for leading skin care products. Oxygen compatibility was determined using autogenous ignition temperature (AIT), oxygen index (OI), and heat of combustion (HoC) testing. AIT, a relative indication of a material's propensity for ignition, is the minimum temperature needed to cause a sample to self-ignite at a given pressure and oxygen concentration. OI, a relative indication of a material's flammability, is the minimum oxygen percentage that, when mixed with nitrogen, will sustain burning. HoC is the absolute value of a material's energy release when burning, if ignition occurs. Products with a high AIT, a high OI, and a low HoC are more compatible in an oxygen-enriched atmosphere (OEA). An acceptability index (AI) based on these 3 factors was calculated for the products, so the testers could rank overall material compatibility in OEAs (Lapin A. Oxygen Compatibility of Materials. International Institute of Refrigeration Commission Meeting; Brighton, England; 1973). RESULTS: Test results for the skin products varied widely. The AIT, OI, HoC, and AI were determined for each product under described circumstances. The AIT results indicate that all products in 99.5% oxygen concentration under pressure will ignite and that a pattern based on the absence or presence of petroleum-based ingredients does not seem to exist. Products containing petrolatum, mineral oil, paraffin, and paraffin wax had a HoC that equaled or exceeded the HoC of gasoline, whereas products without petroleum-based ingredients had a significantly lower HoC. The OI of skin products not containing petrolateum-based ingredients was significantly higher than the OI of products containing it. The AI values the OI as the most important value: the higher the AI, the more acceptable the product is for use with oxygen. The silicone-containing, petroleum-free products received an AI up to 25 times higher than the petrolatum-based products. These findings suggest a wide variation in the safety profiles of skin products. Skin products being considered for use in an OEA should be screened for flammability risks. This screening will allow informed decisions about the fire safety of the products. Further research is indicated.

Burns and injuries from non-electric-appliance fires in low- and middle-income countries Part II. A strategy for intervention using the Haddon Matrix.

A large proportion of burns in developing countries are related to the nature of domestic appliances used for cooking, heating, and lighting. Our overview of the problem elucidated the need for better surveillance with epidemiologic studies, which will more accurately assess the true incidence in vulnerable populations. This paper will create a framework for envisaging new approaches to the problem and begin to evaluate the strengths and weaknesses of proposed interventions. We used the Haddon Matrix to accumulate proposed interventions that encompass a pre-event, event, and post-event timeline. We propose an initial strategic outline plan for interventions based on values that are suited to the problem and the setting, are culturally appropriate, and can be employed in a reasonable period of time for a sustained period to ensure success. Recommended action steps include promoting the use of alternative energy sources, encouraging an integrated approach to finding interdisciplinary solutions, devising a better system of kerosene containerization, re-engineering appliance designs, legislating for enforcement of health and safety standards, taking a holistic approach through government inter-departmental collaboration, formally discouraging corruption, encouraging ventilation of cooking or living areas, implementing building codes, educating consumers, and training caregivers and health and emergency workers.

Fire resistance of Douglas fir (Pseudotsuga menzieesi) treated with borates and natural extractives.

The objective of this study was to determine fire resistance of Douglas fir (Pseudotsuga menzieesi (Mirb.) Franco) specimens treated with borate supplemented aqueous solutions of brutia pine bark powder, acorn powder, sumach leaf powder, and gall-nut powder. Boric acid (BA) and borax (BX) were used as borates which are the most commonly used fire retardants in wood preservation industry. Natural extractives (brutia pine bark powder, sumach leaf powder, acorn powder, and gall-nut powder) were also used which have toxic efficiency against insects and fungi due to their tannin contents. A commercial treatment compound Tanalith-CBC (copper-borate-chromate), which is an impregnation chemical, is used for comparison. The fire test method was performed in three stages: flame stage, without flame stage, and glowing stage. Results indicated that the lowest temperature for flame stage, without flame stage, and glowing stage were obtained for specimens treated with BA and BX mixture (7:3; weight:weight). The lowest mass loss was found for the specimens treated with a mixture of BA and BX. Natural extractives did not improve fire resistance of the samples. However, boric acid and borax had excellent fire retardant effectiveness over untreated and treated samples with natural extractives.