Back to Normal: An Old Physics Route to Reduce SARS-CoV-2 Transmission in Indoor Spaces

We advocate the widespread use of UV-C light as a short-term, easily deployable, and affordable way to limit virus spread in the current SARS-CoV-2 pandemic. Radical social distancing with the associated shutdown of schools, restaurants, sport clubs, workplaces, and traveling has been shown to be effective in reducing virus spread, but its economic and social costs are unsustainable in the medium term. Simple measures like frequent handwashing, facial masks, and other physical barriers are being commonly adopted to prevent virus transmission. However, their efficacy may be limited, particularly in shared indoor spaces, where, in addition to airborne transmission, elements with small surface areas such as elevator buttons, door handles, and handrails are frequently used and can also mediate transmission. We argue that additional measures are necessary to reduce virus transmission when people resume attending schools and jobs that require proximity or some degree of physical contact. Among the available alternatives, UV-C light satisfies the requirements of rapid, widespread, and economically viable deployment. Its implementation is only limited by current production capacities, an increase of which requires swift intervention by industry and authorities.

The associations between thermal variety and health: Implications for space heating energy use

Fossil fuels dominate domestic heating in temperate climates. In the EU, domestic space heating accounts for around 20% of final energy demand. Reducing domestic demand temperatures would reduce energy demand. However, cold exposure has been shown to be associated with adverse health conditions. Using an observational dataset of 77,762 UK Biobank participants, we examine the standard deviation of experienced temperature (named here thermal variety) measured by a wrist worn activity and temperature monitor. After controlling for covariates such as age, activity level and obesity, we show that thermal variety is 0.15°C 95% CI [0.07–0.23] higher for participants whose health satisfaction was ‘extremely happy’ compared to ‘extremely unhappy’. Higher thermal variety is also associated with a lower risk of having morbidities related to excess winter deaths. We argue that significant CO₂ savings would be made by increasing thermal variety and reducing domestic demand temperatures in the healthiest homes. However, great care is needed to avoid secondary health impacts due to mould and damp. Vulnerable households should receive increased attention.

Newborn Service Readiness of Primary Level Health Facilities of Eastern Mountain Region of Nepal

BACKGROUND

Newborn service readiness is facility's observed capacity to provide newborn services and a pre-requisite for quality. Newborn services are priority program of government and efforts are focused on infrastructure and supplies at peripheral health facilities. Study describes health facility readiness for newborn services in four domains of general requirements, equipment, medicines and commodities, and staffing and guidelines.

METHODS

Convergent parallel mixed method using concurrent triangulation was done in public health facilities providing institutional deliveries of two randomly selected districts- Taplejung and Solukhumbu of Eastern Mountain Region of Nepal. Face to face interview and observation of facilities were done using structured questionnaire and checklist; in-depth interviews were done using interview guideline from November 2016 to January 2017. Ethical clearance was taken. Descriptive analysis and deductive thematic analysis were done.

RESULTS

Mean score of newborn service readiness was 68.7±7.1 with range from 53.3 to 81.4 out of 100. Domains of general requirement, equipment, medicine and commodity, supervision, staffing and guideline were assessed. The gaps identified in general requirements were availability of uninterrupted power supply, means of communication and referral vehicle. Clean wrappers and heater for room temperature maintenance were identified during interviews to be part of the readiness. All health facilities had trained staff while retention of skill was of concern. There was felt need of enforcing adequate training coverage to suffice the need of human resources in remote.

CONCLUSIONS

Efforts of improving transportation, heater for room temperature maintenance, trainings with skill retention strategy, utilization of guidelines, availability of skilled birth attendance could result increased and improved newborn service readiness.

Comparing Forced-Air to Resistive-Polymer Warming for Perioperative Temperature Management: A Retrospective Study

PURPOSE

Compare perioperative temperature management between forced-air warming (FAW) and resistive-polymer heating blankets (RHBs).

DESIGN

A retrospective, quasi-experimental study.

METHODS

Retrospective data analysis of nonspine orthopedic cases (N = 426) over a one-year period including FAW (n = 119) and RHBs (n = 307).

FINDINGS

FAW was associated with a significantly higher final intraoperative temperature (P = .001, d = 0.46) than the RHB. The incidence of hypothermia was not found to be significantly different at the end (P = .102) or anytime throughout surgery (P = .270). Of all patients who started hypothermic, the FAW group had a lower incidence of hypothermia at the end of surgery (P = .023).

CONCLUSIONS

FAW was associated with higher final temperatures and a greater number of normothermic patients than RHBs. However, no causal relationship between a warming device and hypothermia incidence should be assumed.

Maternal depression as a risk factor for children's inadequate housing conditions

Depression among mothers with young children is an important public health issue that not only has implications for their own well-being, but can also potentially affect their children's health and developmental trajectories. This study explored the extent to which maternal depression is a risk factor for inadequate housing conditions related to utilities, a noteworthy risk factor for poor child health. Using data on 2965 mothers and children from a national urban cohort of U.S. births in 1998-2000, we estimated multivariate logistic regression models of associations between maternal depression during the postpartum year and a U.S. Department of Housing and Urban Development (HUD) measure of severely inadequate housing due to heating issues, as well as a broader measure of energy insecurity that encompasses various types of utility problems. We also considered outcomes that incorporated housing instability and food insecurity in conjunction with housing inadequacy. Mothers who experienced depression had about 60% higher odds of experiencing severely inadequate housing due to heat (OR: 1.57) and 70% higher odds of experiencing energy insecurity (OR: 1.69) compared to mothers who did not experience depression. Maternal depression was even more strongly associated with multiple hardships in the forms of housing inadequacy plus housing instability and/or food insecurity than it was with housing inadequacy. This study provides robust evidence that maternal depression is a risk factor for inadequate housing and multiple hardships during a critical period of children's development. The findings suggest that policy efforts should not occur in mental health, housing, and food security silos.

Maternal depression as a risk factor for children's inadequate housing conditions

Depression among mothers with young children is an important public health issue that not only has implications for their own well-being, but can also potentially affect their children's health and developmental trajectories. This study explored the extent to which maternal depression is a risk factor for inadequate housing conditions related to utilities, a noteworthy risk factor for poor child health. Using data on 2965 mothers and children from a national urban cohort of U.S. births in 1998-2000, we estimated multivariate logistic regression models of associations between maternal depression during the postpartum year and a U.S. Department of Housing and Urban Development (HUD) measure of severely inadequate housing due to heating issues, as well as a broader measure of energy insecurity that encompasses various types of utility problems. We also considered outcomes that incorporated housing instability and food insecurity in conjunction with housing inadequacy. Mothers who experienced depression had about 60% higher odds of experiencing severely inadequate housing due to heat (OR: 1.57) and 70% higher odds of experiencing energy insecurity (OR: 1.69) compared to mothers who did not experience depression. Maternal depression was even more strongly associated with multiple hardships in the forms of housing inadequacy plus housing instability and/or food insecurity than it was with housing inadequacy. This study provides robust evidence that maternal depression is a risk factor for inadequate housing and multiple hardships during a critical period of children's development. The findings suggest that policy efforts should not occur in mental health, housing, and food security silos.

Thermal environment in eight low-energy and twelve conventional Finnish houses

We assessed the thermal environment of eight recently built low-energy houses and twelve conventional Finnish houses. We monitored living room, bedroom and outdoor air temperatures and room air relative humidity from June 2012 to September 2013. Perceived thermal environment was evaluated using a questionnaire survey during the heating, cooling and interim seasons. We compared the measured and perceived thermal environments of the low-energy and conventional houses. The mean air temperature was 22.8 °C (21.9-23.8 °C) in the low-energy houses, and 23.3 °C (21.4-26.5 °C) in the conventional houses during the summer (1. June 2013-31. August 2013). In the winter (1. December 2012-28. February 2013), the mean air temperature was 21.3 °C (19.8-22.5 °C) in the low-energy houses, and 21.6 °C (18.1-26.4 °C) in the conventional houses. The variation of the air temperature was less in the low-energy houses than that in the conventional houses. In addition, the occupants were on average slightly more satisfied with the indoor environment in the low-energy houses. However, there was no statistically significant difference between the mean air temperature and relative humidity of the low-energy and conventional houses. Our measurements and surveys showed that a good thermal environment can be achieved in both types of houses.

A correlation linking the predicted mean vote and the mean thermal vote based on an investigation on the human thermal comfort in short-haul domestic flights

The results of an experimental investigation on the human thermal comfort inside the cabin of some Airbus A319 aircrafts during 14 short-haul domestic flights, linking various Italian cities, are presented and used to define a correlation among the predicted mean vote (PMV), a procedure which is commonly used to assess the thermal comfort in inhabited environments, and the equivalent temperature and mean thermal vote (MTV), which are the parameters suggested by the European Standard EN ISO 14505-2 for the evaluation of the thermal environment in vehicles. The measurements of the radiant temperature, air temperature and relative humidity during flights were performed. The air temperature varied between 22.2 °C and 26.0 °C; the relative humidity ranged from 8.7% to 59.2%. The calculated values of the PMV varied from -0.16 to 0.90 and were confirmed by the answers of the passengers. The equivalent temperature was evaluated using the equations of Fanger or on the basis of the values of the skin temperature measured on some volunteers. The correlation linking the thermal sensation scales and zones used by the PMV and the MTV resulted quite accurate because the minimum value of the absolute difference between such environmental indexes equalled 0.0073 and the maximum difference did not exceed the value of 0.0589. Even though the equivalent temperature and the MTV were specifically proposed to evaluate the thermal sensation in vehicles, their use may be effectively extended to the assessment of the thermal comfort in airplanes or other occupied places.

Annual verifications--a tick-box exercise?

With the onus on healthcare providers and their staff to protect patients against all elements of 'avoidable harm' perhaps never greater, Gwen Walker, a highly experienced infection prevention control nurse specialist, and David Williams, MD of Approved Air, who has 30 years' experience in validation and verification of ventilation and ultraclean ventilation systems, examine changing requirements for, and trends in, operating theatre ventilation. Validation and verification reporting on such vital HVAC equipment should not, they argue, merely be viewed as a 'tick-box exercise'; it should instead 'comprehensively inform key stakeholders, and ultimately form part of clinical governance, thus protecting those ultimately named responsible for organisation-wide safety at Trust board level'.

TR/19 update--key concerns addressed

With trade association for the heating, ventilating, air-conditioning, and refrigeration sectors, the Building and Engineering Services Association (B&ES), having recently updated its 'TR/19' guidance document--dealing with the internal cleanliness of ventilation systems--Health Estate Journal (HEJ) asks Richard Norman (RN), chairman of the Association's Ventilation Hygiene Group Branch, and MD of specialist ventilation cleaning services provider, Indepth Hygiene, about the changes, and why the revisions were needed.

Water heaters subject to new regulations

On 26 September 2015 the Ecodesign and Energy Labelling Directives for water heaters (Lot 2) come into force, meaning that water-heating products sold in the UK and other countries in the European Economic Area will need to meet minimum energy performance criteria in order to be legally placed on the market, and will require an energy label. Here Alan Clarke, technical support manager at Heatrae Sadia, explains more.

Measuring hygiene and health perfomance of buildings: a multidimensional approach

This paper proposes an innovative and transparent methodology to support the "ASL Milano" (Local Health Agency) in the hygiene and health evaluation of construction projects, in order to highlight their positive and negative performance beyond the requirements imposed by the current laws and regulations regarding buildings' hygiene performance, which are too old and therefore unsuitable to ascertain the real quality of indoor environments. The compliance with laws or regulations, mostly out of date, and the assessment of performance involving only a part of the current emerging needs and problems, in fact, should be considered as a necessary, although not a sufficient step, to ensure high quality indoors. Consequently, it is necessary to identify and test an assessment tool which could provide an effective and flexible support for the development of hygiene and health statements regarding projects at building scale (new construction, conversion of the existing, rehabilitation, extension, change of use, etc). The assessment tool suggested by this paper is tailored for the metropolitan area of the city of Milan, but its evaluation framework could be developed and applied to other contexts.

Housing improvements for health and associated socio-economic outcomes

BACKGROUND

The well established links between poor housing and poor health indicate that housing improvement may be an important mechanism through which public investment can lead to health improvement. Intervention studies which have assessed the health impacts of housing improvements are an important data resource to test assumptions about the potential for health improvement. Evaluations may not detect long term health impacts due to limited follow-up periods. Impacts on socio-economic determinants of health may be a valuable proxy indication of the potential for longer term health impacts.

OBJECTIVES

To assess the health and social impacts on residents following improvements to the physical fabric of housing.

SEARCH METHODS

Twenty seven academic and grey literature bibliographic databases were searched for housing intervention studies from 1887 to July 2012 (ASSIA; Avery Index; CAB Abstracts; The Campbell Library; CINAHL; The Cochrane Library; COPAC; DH-DATA: Health Admin; EMBASE; Geobase; Global Health; IBSS; ICONDA; MEDLINE; MEDLINE In-Process & Other Non-Indexed Citations; NTIS; PAIS; PLANEX; PsycINFO; RIBA; SCIE; Sociological Abstracts; Social Science Citations Index; Science Citations Index expanded; SIGLE; SPECTR). Twelve Scandinavian grey literature and policy databases (Libris; SveMed+; Libris uppsök; DIVA; Artikelsök; NORART; DEFF; AKF; DSI; SBI; Statens Institut for Folkesundhed; Social.dk) and 23 relevant websites were searched. In addition, a request to topic experts was issued for details of relevant studies. Searches were not restricted by language or publication status.

SELECTION CRITERIA

Studies which assessed change in any health outcome following housing improvement were included. This included experimental studies and uncontrolled studies. Cross-sectional studies were excluded as correlations are not able to shed light on changes in outcomes. Studies reporting only socio-economic outcomes or indirect measures of health, such as health service use, were excluded. All housing improvements which involved a physical improvement to the fabric of the house were included. Excluded interventions were improvements to mobile homes; modifications for mobility or medical reasons; air quality; lead removal; radon exposure reduction; allergen reduction or removal; and furniture or equipment. Where an improvement included one of these in addition to an included intervention the study was included in the review. Studies were not excluded on the basis of date, location, or language.

DATA COLLECTION AND ANALYSIS

Studies were independently screened and critically appraised by two review authors. Study quality was assessed using the risk of bias tool and the Hamilton tool to accommodate non-experimental and uncontrolled studies. Health and socio-economic impact data were extracted by one review author and checked by a second review author. Studies were grouped according to broad intervention categories, date, and context before synthesis. Where possible, standardized effect estimates were calculated and statistically pooled. Where meta-analysis was not appropriate the data were tabulated and synthesized narratively following a cross-study examination of reported impacts and study characteristics. Qualitative data were summarized using a logic model to map reported impacts and links to health impacts; quantitative data were incorporated into the model.

MAIN RESULTS

Thirty-nine studies which reported quantitative or qualitative data, or both, were included in the review. Thirty-three quantitative studies were identified. This included five randomised controlled trials (RCTs) and 10 non-experimental studies of warmth improvements, 12 non-experimental studies of rehousing or retrofitting, three non-experimental studies of provision of basic improvements in low or mIddle Income countries (LMIC), and three non-experimental historical studies of rehousing from slums. Fourteen quantitative studies (42.4%) were assessed to be poor quality and were not included in the synthesis. Twelve studies reporting qualitative data were identified. These were studies of warmth improvements (n = 7) and rehousing (n = 5). Three qualitative studies were excluded from the synthesis due to lack of clarity of methods. Six of the included qualitative studies also reported quantitative data which was included in the review.Very little quantitative synthesis was possible as the data were not amenable to meta-analysis. This was largely due to extreme heterogeneity both methodologically as well as because of variations in the intervention, samples, context, and outcome; these variations remained even following grouping of interventions and outcomes. In addition, few studies reported data that were amenable to calculation of standardized effect sizes. The data were synthesised narratively.Data from studies of warmth and energy efficiency interventions suggested that improvements in general health, respiratory health, and mental health are possible. Studies which targeted those with inadequate warmth and existing chronic respiratory disease were most likely to report health improvement. Impacts following housing-led neighbourhood renewal were less clear; these interventions targeted areas rather than individual households in most need. Two poorer quality LMIC studies reported unclear or small health improvements. One better quality study of rehousing from slums (pre-1960) reported some improvement in mental health. There were few reports of adverse health impacts following housing improvement. A small number of studies gathered data on social and socio-economic impacts associated with housing improvement. Warmth improvements were associated with increased usable space, increased privacy, and improved social relationships; absences from work or school due to illness were also reduced.Very few studies reported differential impacts relevant to equity issues, and what data were reported were not amenable to synthesis.

AUTHORS' CONCLUSIONS

Housing investment which improves thermal comfort in the home can lead to health improvements, especially where the improvements are targeted at those with inadequate warmth and those with chronic respiratory disease. The health impacts of programmes which deliver improvements across areas and do not target according to levels of individual need were less clear, but reported impacts at an area level may conceal health improvements for those with the greatest potential to benefit. Best available evidence indicates that housing which is an appropriate size for the householders and is affordable to heat is linked to improved health and may promote improved social relationships within and beyond the household. In addition, there is some suggestion that provision of adequate, affordable warmth may reduce absences from school or work.While many of the interventions were targeted at low income groups, a near absence of reporting differential impacts prevented analysis of the potential for housing improvement to impact on social and economic inequalities.

Examination of thermal comfort in a hospital using PMV-PPD model

In this study, the performance of air conditioning system and the level of thermal comfort are determined in a state hospital located in Kermanshah city in the west of Iran in winter and summer using the Predicted Mean Vote (PMV) model which has been presented by ISO-7730 (2005). The Predicted Mean Vote (PMV) and the Predicted Percentage Dissatisfied (PPD) indices were computed using the data acquired from the experimental measurements performed in the building. The results showed that the values of PMV in some parts of the building, both for men and women, are not within the standard acceptable range defined by ISO. It was found that the most thermal problems in winter occur in morning work shift, and the worst thermal conditions in summer occur in noon work shift. The t-test results revealed that there is no noticeable difference between the thermal conditions of some rooms and those of the surroundings.

[Assessment of the hygienic and sanitary conditions of housing in a sample in Chieti (central Italy)]

The study describes the housing conditions of 106 dwellings in the town of Chieti (Abruzzo region, central Italy), inspected by Local Health Authority, in the period between the 1st of January 2009 and the 28th of February 2011. In 59.4% of them lived Italians, while in the remaining 40.6% lived foreigners. 35.8% of the houses met minimum law requirements, 24.5% were anti-hygienic, 24.5% anti-hygienic and overcrowded, 13.2% overcrowded, 1.9% uninhabitable. The main issues were moisture and molds (52.8%). The second one was the inadequacy of floor area in relation with inhabitants (37.7%). Other problems were bedrooms (9.4%), baths (8.5%) and kitchens not complying minimum law requirements, but also not sufficient both ceiling hights (3.7%) and windows (2.8%) of rooms. Considering that human population in richest countries spend up to 90% of their lives in indoor environment, especially at home, the links between housing and health are really strong, and more must be done to improve general consideration of these themes both in general population and involved professionists (i.e. physicians, other health professionists, social workers, architects and engineers).

Epidemiology of unintentional carbon monoxide fatalities in the UK

This study aims to describe the epidemiology of unintentional non-fire related CO fatalities in the UK and to relate this information to sources of CO. Data from the CO-Gas Safety Society (COGSS) database was analysed and compared with data from the English House Condition Survey (EHCS). There were 462 deaths from the COGSS database, from 1 January 1996 to 31 December 2007 inclusive. The relative risk for death due to non-gas vs gas fuels was 10.52 (95% CI 7.71-14.34). The main weakness of the study is the likely underascertainment of CO deaths in the database. However, this study has identified specific risk factors for CO-related deaths in the UK; the use of non-gas fuels has not previously been highlighted as a significant cause of CO poisoning, and the relative risk (although not the absolute risk) of CO-related fatalities from these fuels is substantial.

[Physiological and hygienic rationale for the duration of exposure to the heating environment and comfortable thermal conditions during a workshift]

The strain in different functional systems of human body maintaining thermal homeostasis that develops during work under heating conditions results in impaired working capacity and efficiency and may be harmful to health. One of the most efficacious measures is the reduction of exposure to the adverse conditions and its rational alternation with rest in the comfortable environment. Based on the mathematical and statistical analysis of the results of multiple-factor experiments, we derived a multiple regression equation describing the quantitative dependence of the integral index of human body thermal regime on the totality of factors responsible for thermal strain. The equation permits to determine the heat content in the human body formed by exothermal and endothermal strain, to estimate the contribution of each individual factor, and to predict the risk of overheating in order to take measures for reducing the thermal strain. Recommendations are proposed on the duration of thermal exposure during a workshift depending on the overheating risk level and on the optimal relationship between the duration of staying in the heating microclimate and the duration of the rest (work) in the comfortable environment.

A cure for the common cold

As the U.K.'s largest organisation, with an annual purchasing budget of around pounds 17 billion, the NHS has an enormous part to play in reducing the country's energy consumption and emissions. Graham Williamson, general manager of Commercial Heating at Ideal Commercial Heating, considers the key measures healthcare facility operators can take to save energy, and how heating companies can help.

[Thermal comfort in perioperatory risk's evaluation]

Studies till now conducted about operating rooms' microclimate have been focused mainly on operators' thermal comfort, considering that uneasiness conditions may compromise their working performance. In last years, nevertheless, the anesthesiologic community recalled attention on patients' risks determined by perioperatory variations of normothermia, underlining the necessity of orientating studies to individuate microclimate characteristics act to guarantee thermal comfort of the patient too. Looking at these considerations, a study has been conducted in the operating rooms of the hospital-university Firm and the n.1 USL of Sassari, finalized, on one hand, to determinate microclimate characteristics of the operating blocks and to evaluate operators' and patients' thermal comfort, on the other to individuate, through a software simulation, microclimate conditions that ensure contemporarily thermal comfort for both the categories. Results confirm the existence of a thermal "gap" among operators and patients, these last constantly submitted to "cold-stress", sometimes very accentuated. So, we underline microclimate's importance in operating rooms, because there are particular situations that can condition perioperatory risks. Moreover it can be useful to integrate risk's classes of the American Society of Anestesiology (ASA) with a score attributed to the PMV/PPD variation, reaching more real operatory risk indicators.

Polycyclic aromatic hydrocarbons in dustfall in Tianjin, China

Atmospheric dustfall samples from 23 locations in Tianjin, China, were collected and analyzed for 16 polycyclic aromatic hydrocarbons (PAHs) classified by the Environmental Protection Agency as priority pollutants from March 2002 to March 2003. SigmaPAH16 (sum of 16 PAH compounds) concentrations in the dustfall collected during heating season ranged from 2.5 to 85.5 mug/g, while that during the non-heating season varied from 1.0 to 48.2 microg/g dry weight. The dominant components in the heating season included naphthalene, phenanthrene, fluoranthene, and chrysene, while naphthalene, fluorene, phenanthrene, and fluoranthene were dominant during the non-heating season. Compared with the non-heating season, the heating season was characterized by a higher fraction of high-molecular-weight PAHs with four to six rings with exception of the samples from the east industrial area. The east industrial area had more significant correlations between individual PAH compounds, and more discrete triangular components of three-, four-, five- and six-ring PAHs. No significant correlations were observed between the PAHs concentrations and total organic carbon (TOC) in the dustfall samples. The deposition fluxes of sigmaPAH15 (sum of 15 PAHs except naphthalene), sigmaPAH6 (sum of 6 carcinogenic PAHs recommended by IARC) and benzo[a]pyrene (BaP) from atmospheric deposition to the whole area were estimated as 1911, 196, and 53 microg/m2/year, respectively. The deposition rates for PAH compounds in the east industrial area were higher than those in the urban and rural areas. Furthermore, the deposition contribution of PAHs during domestic heating season in winter was not significant relative to the annual inputs.

Evaluation of the effectiveness of the Pastormaster method for disinfection of legionella in a hospital water distribution system

The Pastormaster method consists of heating the water of hospital distribution systems at a specific point to a sufficient temperature for a minimum amount of time to eradicate legionella. The object of this study was to evaluate the effectiveness of the Pastormaster method for legionella disinfection in a hospital environment. A two-phase procedure was performed: hydraulic optimization of the water supply circuit, and implementation of the Pastormaster method. Water samples were taken at 10 representative points in the hospital hot-water system and cultured microbiologically. Other physical and chemical measurements were also determined. Implementation of the Pastormaster method and correction of the deficiencies identified during a hydraulic system audit confirmed the absence of legionella in the hospital water distribution system. The combination of implementation of the Pastormaster method and conduction of a hydraulic audit designed to identify and remedy any possible problems in water circulation is effective in minimizing the risk of legionella contamination in hospital water distribution systems.

Water disinfection with ozone, copper and silver ions, and temperature increase to control Legionella: seven years of experience in a university teaching hospital

The efficacy of ozonation, copper-silver ionization and increased temperature in controlling Legionella spp. in the hot water distribution networks of a university hospital was evaluated. Two separate water distribution networks were studied; network 1 which supplies the surgical intensive care units, and network 2 which supplies the medical intensive care units and the emergency room. Network 1 has been disinfected by ozonation since 1995, and network 2 has been disinfected by ionisation since 1999. The hot water temperature was increased from 50 to 65 degrees C in 1998 and 2000 in networks 1 and 2, respectively. Water samples and swabs of the water outlets were cultured for Legionella spp. between four and six times each year, providing data before and after implementation of the disinfection procedures. There was no significant difference in the proportion of samples positive for Legionella spp. after ozonation in network 1 or after ionization in network 2. In both networks, there was a significant reduction in legionella isolates after increasing the hot water temperature to 65 degrees C. Maintaining the hot water temperature above 50 degrees C throughout both networks proved to be the most effective control measure in our hospital.

[Air quality control systems: heating, ventilating, and air conditioning (HVAC)]

After a brief illustration of the principal layout schemes of Heating, Ventilating, and Air Conditioning (HVAC), the first part of this paper summarizes the standards, both voluntary and compulsory, regulating HVAC facilities design and installation with regard to the question of Indoor Air Quality (IAQ). The paper then examines the problem of ventilation systems maintenance and the essential hygienistic requirements in whose absence HVAC facilities may become a risk factor for people working or living in the building. Lastly, the paper deals with HVAC design strategies and methods, which aim not only to satisfy comfort and air quality requirements, but also to ensure easy and effective maintenance procedures.

Physiological and Subjective Responses in the Elderly When Using Floor Heating and Air Conditioning Systems

The purpose of this study was to investigate the effects of a floor heating and air conditioning system on thermal responses of the elderly. Eight elderly men and eight university students sat for 90 minutes in a chair under the following 3 conditions: air conditioning system (A), floor heating system (F) and no heating system (C). The air temperature of sitting head height for condition A was 25 degrees C, and the maximum difference in vertical air temperature was 4 degrees C. The air and floor temperature for condition F were 21 and 29 degrees C, respectively. The air temperature for condition C was 15 degrees C. There were no significant differences in rectal temperature and mean skin temperature between condition A and F. Systolic blood pressure of the elderly men in condition C significantly increased compared to those in condition A and F. No significant differences in systolic blood pressure between condition A and F were found. The percentage of subjects who felt comfortable under condition F was higher than that of those under condition A in both age groups, though the differences between condition F and A was not significant. Relationships between thermal comfort and peripheral (e.g., instep, calf, hand) skin temperature, and the relationship between thermal comfort and leg thermal sensation were significant for both age groups. However, the back and chest skin temperature and back thermal sensation for the elderly, in contrast to that for the young, was not significantly related to thermal comfort. These findings suggested that thermal responses and physiological strain using the floor heating system did not significantly differ from that using the air conditioning system, regardless of the subject age and despite the fact that the air temperature with the floor heating system was lower. An increase in BP for elderly was observed under the condition in which the air temperature was 15 degrees C, and it was suggested that it was necessary for the elderly people to heat the room somehow in winter. Moreover, it is particularly important for elderly people to avoid a decrease in peripheral skin temperature, and maintain awareness of the warmth of peripheral areas, such as the leg, in order to ensure thermal comfort.

Risk factors associated with neonatal hypothermia during cleaning of newborn infants in labour rooms

Cleaning newborn infants with coconut oil shortly after birth is a common practice in Malaysian labour rooms. This study aimed: (1) to determine whether this practice was associated with a significant decrease in the core temperature of infants; and (2) to identify significant risk factors associated with neonatal hypothermia. The core temperature of 227 randomly selected normal-term infants immediately before and after cleaning in labour rooms was measured with an infrared tympanic thermometer inserted into their left ears. Their mean post-cleaning body temperature (36.6 degrees C, SD = 1.0) was significantly lower than their mean pre-cleaning temperature (37.1 degrees C, SD = 1.0; p < 0.001). Logistic regression analysis showed that the risk factors significantly associated with pre-cleaning hypothermia (< 36.5 degrees C) were: (1) not being placed under radiant warmer before cleaning p = 0.03); and (2) lower labour room temperature (p < 0.001). Logistic regression analysis also showed that the risk factors significantly associated with post-cleaning hypothermia were: (1) lower labour room temperature (p < 0.001); (2) lower pre-cleaning body temperature (p < 0.001); and (3) longer duration of cleaning (p = 0.002). In conclusion, to prevent neonatal hypothermia, labour room temperature should be set at a higher level and cleaning infants in the labour room should be discouraged.

Human exposure to electric and magnetic fields from RF sealers and dielectric heaters--a COMAR technical information statement

Radio frequency (RF) sealers and dielectric heaters, operating between 3 and 100 MHz, are used for a variety of industrial applications. There is concern about the safety of such devices because measurements during operation often show leakage of electric and magnetic fields, as well as induced currents in the body, that exceed RF exposure guidelines. Both the leakage of fields and the absorption of RF energy by an operator can be reduced by shielding, proper grounding of the sealers, isolation of the operator from ground, and increasing the distance between the sealer and the operator. Several national and international standards now include limits on body-to-ground and contact currents for humans. Based on present knowledge of the biological effects of RF fields and the reported exposures from such devices, COMAR recommends that the leakage field strengths from RF sealers and dielectric heaters, as well as body-to-ground and contact currents, be monitored and exposure to workers be limited so as to meet the recommended RF exposure guidelines.

A proposal of optimal floor surface temperature based on survey of literatures related to floor heating environment in Japan

Due to comprehensive research on floor heating in Japan and abroad over the last twenty years it is possible today to predict these combinations of comfortable conditions. The specific aim of this investigation is to obtain experimental data upon which the comfortable range of the floor surface temperature could be based, thereby providing a practical and more satisfactory design guide. Accordingly literatures on floor heating are collected and investigated with the purpose of revealing what the comfort range of floor surface temperature ought to be. Authors tried to obtain a comfortable and permissible floor surface temperature and then reconfirm the maximum comfortable range so that they can propose a reasonable comfortable floor surface temperature and make it fit for practical and extensive use. After synthesizing all the comfortable and permissible values reported in many other papers, this paper finally advances a suggestion on the optimal and permissible floor surface temperatures. Results concerning this subject are as follows. The lowest floor surface temperature would be limited to 25 degrees C, and it is 21-23 degrees C for the air temperature so that more than 80% subjects can be expected to be comfortable within this recommended temperature interval.

The analysis of thermal comfort requirements through the simulation of an occupied building

Building simulation usually focuses on the study of physical indoor parameters, but we must not forget the main aim of a house: to provide comfort to the occupants. This study was undertaken in order to build a complete tool to model thermal behaviour that will enable the prediction of thermal sensations of humans in a real environment. A human thermoregulation model was added to TRNSYS, a building simulation program. For our purposes, improvements had to be made to the original physiological model, by refining the calculation of all heat exchanges with the environment and adding a representation of clothes. This paper briefly describes the program, its modifications, and compares its results with experimental ones. An example of potential use is given, which points out the usefulness of such models in seeking the best solutions to reach optimal environmental conditions for global, and specially local comfort, of building occupants.

State regulation of hospital water temperature

OBJECTIVE

The purpose of this study was to determine current regulations and policies in the United States concerning maximal water temperatures in acute care hospitals.

DESIGN

A standardized questionnaire administered by telephone to health department officials from 50 states and the District of Columbia.

SETTING

State Health Departments in the 50 states and the District of Columbia.

RESULTS

All states responded to the survey. Respondents from 39 states (77%) reported regulating maximum allowable hospital water temperature at a mean of 116 degrees F (median, 120 degrees F; mode 110 degrees F; range, 110 degrees F to 129 degrees F). Twelve states (23%) have no regulations for maximum water temperature. Of the 39 states regulating maximum water temperature, 30 (77%) routinely monitor hospital compliance. Nine states (23%) conduct inspections only in response to a complaint or incident.

CONCLUSIONS

There is great variation among the states with respect to the existence, enforcement, and specific regulations controlling hospital water temperature. Risk-benefit and cost-effectiveness analyses would help to assess the risk of scald injuries at water temperatures that will inhibit microbial contamination.

Design considerations for heating, air conditioning, and exhaust systems in critical care units

Air quality, temperature control, and air movement directly affect infection control, comfort, and safety in critical care units. This article explains basic concepts in the heating, ventilation, and air conditioning that affect patient care. Functional requirements must be determined early in the design process and discussed with clinicians, engineers, and architects to assure understanding and correct design.

Visual safety of quartz linear lamps

A quartz linear lamp (QLL) is a compact infra-red (i.r.) heating lamp. It consists of a tungsten filament in a quartz envelope, which for space heating purposes is surrounded by a ruby coloured filter. The filament runs at about 2400 K and produces i.r. radiation with a peak output at 1200 nm. The lamps are widely used for space heating and are normally fitted with a parabolic reflector. There are no statutory criteria for potential visual hazards resulting from the use of such lamps in the U.K. The ACGIH has produced a provisional set of rules on light and near i.r. This paper reviews potential hazards to the eye in the context of the ACGIH rules and the output of QLL heaters. The heaters produce no u.v. or blue light hazards. The brightness and heat of the lamp is sufficient to produce an aversion response which will prevent retinal thermal damage from inadvertent viewing. The probability of retinal thermal injury from an i.r.-A image focused on the retina is examined and it is shown that there is no risk at normal viewing distances. To prevent any risk of cataractogenesis, the rules provide for an upper limit of irradiance (TLV) at the eye of 100 W m-2 in the i.r.-A band; the paper examines the potential hazard from longer wavelengths and concludes that they do not present a hazard with this type of heating. The conclusion is that QLL heaters used for space heating in accordance with manufacturer's instructions present no hazard to the eye.

A survey of technology and temperature control on a neonatal unit in Kathmandu, Nepal

An assessment of the incubators in use at the Kathmandu Maternity Hospital neonatal unit was undertaken; this was followed by a prospective survey of neonatal temperatures on the unit. In the incubator assessment 11 studies were carried out in five incubators. Three of the thermostats in the five incubators did not work at all and those in the other two incubators were more than 3 degrees C inaccurate. All the incubator thermometers gave recordings less than the actual temperature (with a range of error: 1.3-4.4 degrees C). Six out of the 11 babies studied were hypothermic (defined as rectal temperature < 36 degrees C). In the prospective survey of temperatures a high incidence of hypothermia was found on the neonatal unit at the time of first temperature measurement (64 per cent had a rectal temperature of < 36 degrees C). A significant association between admission hypothermia and mortality was noted. Sixteen per cent (10/64) of babies admitted with temperatures < 36 degrees C died within the first week, compared to 0 (0/36) of those admitted with temperatures > or = 36 degrees C.

Effective methods of in-line intravenous fluid warming at low to moderate infusion rates

Three methods of warming intravenous (IV) fluids were examined. An in-line blood warmer was generally ineffective at flow rates of < 250 mL/hr but did produce temperatures of 30 to 31 degrees C at the catheter when the infusion rate was 500 to 1,000 mL/hr and the tubing was insulated. An in-line hot water bath produced temperatures of > or = 30 degrees C at flow rates of 200 to 1,000 mL/hr with uninsulated tubing. The addition of insulation maintained on infusate temperature of > or = 30 degrees C at a rate of 100 mL/hr. Application of a K-Thermia pad to the IV tubing close to the patient maintained an infusate temperature of > or = 30 degrees C at rates of 50 to 200 mL/hr. Warming at rates of 200 to 1,000 mL/hr is most effective with an in-line hot water bath. Warming at low infusion rates is best accomplished with a K-Thermia pad. The use of in-line blood warmers for routine fluid warming is ineffective.

Microwave warming of peritoneal dialysis fluid

A nursing research study was undertaken to determine whether biochemical composition of peritoneal dialysate fluid was altered with microwave heating and whether the external bag temperature of the heated dialysate was a reliable reflection of the actual fluid temperature. No significant laboratory changes were found in the control, heated, or superheated solutions. By closely following established time frames for specific bag solution volume, agitation of fluid prior to instillation, and external temperature check with specific minimum and maximum acceptable temperatures, peritoneal dialysate can be microwaved and used safely.

Efficiency of the Thermal Jacket on the delivered temperature of prewarmed crystalloid intravenous fluid

Warming of intravenous fluids can decrease the incidence of hypothermia in surgical patients. A quasi-experimental research design was used to compare the delivered temperature of fluids using a conventional blood warmer and the Thermal Jacket, an insulation device designed for intravenous fluid bags. Fluids were divided into one control and three experimental groups. Fluids were initially either room temperature (22.05 +/- 0.45 degrees C) or prewarmed to 41.45 +/- 1.05 degrees C and infused using no temperature maintenance device, a Thermal Jacket, or a water bath blood warmer. Temperatures were recorded at 10-minute intervals at flow rates ranging from 100 to 1,000 mL/hr. Analysis of variance showed a highly significant difference between the delivered temperatures using the various temperature maintenance devices, as well as varying flow rates. The Thermal Jacket, used with prewarmed intravenous fluids, was as effective as the conventional method of delivering warmed fluids. Also, within the range of flow rates studied, faster flow rates tended to yield higher delivered temperatures.