Analysis of radon mitigation methods: 10-year review.

Exposure to the radon gas within a building can result in an increased risk of lung cancer. To minimise the health risk, indoor radon concentrations can be reduced using well-established mitigation methods. The performance of various radon reduction methods, their combination as well as other factors that can impact the efficiency of radon mitigation, were analysed using data collected from approximately 2,800 dwellings that had installed radon mitigation techniques during the period 2007 to 2017. As demonstrated previously (Hodgson 2011), active methods are the most effective at reducing high concentrations of radon to below the Action and Target Levels (200 Bq m-3 and 100 Bq m-3 respectively). Reduction factors of up to 5.5 using single active methods and 8.3 using a combination of active methods were estimated in this study. For indoor radon levels greater than 1,000 Bq m-3, the Active Sump remained the most efficient technique, with the Active Underfloor Ventilation being the second most effective method. Passive methods alone or in combination with other passive methods offered moderate reductions at high radon concentration. Of the passive methods, Underfloor Ventilation was found to have the highest performance with a reduction factor of 1.8. The conclusions of this study should be used to update guidance for stakeholders including householders, contractors, radon awareness campaigns and the UKradon.org website.

Variations in the concentration of radon in parts of the Ogof Ffynnon Ddu system, Penwyllt, South Wales and estimates of doses to recreational cavers.

A new winter and summer investigation of radon concentrations in parts of the Ogof Ffynnon Ddu system at Penwyllt, South Wales, has been carried out using 100 environmental National Radiological Protection Board track etch detectors. Fifty detectors were installed in the system in December 1998 and again in August 1999 for a period of a month. The data obtained confirm that the system has moderately high radon concentrations with a system mean of 2318 Bq m(-3) in winter and 2844 Bq m(-3) in summer. Traverse means have a summer high of 3094 Bq m(-3) for OFDI to Cwm Dwr and a winter low of 1946 Bq m(-3). The extremely high concentrations approaching 20,000 Bq m(-3), reported previously from the system (Hyland, 1995), have not been reproduced. The data show that the airflow directions at the entrances are not what might have been predicted. Air appears to be largely continuously emerging from the lowest entrance but, at the higher entrances, conversely to the predictions, in winter air enters and in summer appears to be coming out or is variable. Internally, there are sites that in winter have very low radon concentrations that can only be explained by the ingress of fresh air. These are not matched in the summer experiment, again indicating that ingress of fresh air to some parts of the system is very variable. The data illustrate the complexity of airflow within a multi-entrance system but behind these variations several mean concentrations can be obtained from which an approximation of the dose likely to be received can be calculated. Using the maximum mean concentration obtained, 3094 Bq m(-3), and using the latest dose conversion, a 10 h underground trip in the Ogof Ffynnon Ddu system yields a calculated dose of 0.12 mSv. Given that the recommended limit for a member of the public is 1 mSv, this dose would be reached after about 80 h of caving in the system.

Patient-centered measurement at an academic medical center.

BACKGROUND: Harborview Medical Center (Seattle, Wash) has collected patient data on operations since 1988 and has participated in the University HealthSystem Consortium's (UHC; Oak Brook, III) patient satisfaction measurement program since 1996. The patient feedback program is intended to provide data suitable for the quality improvement process and benchmark Harborview's performance against that of other academic medical centers (AMCs). USE OF PATIENT FEEDBACK AT HARBORVIEW: The Picker Institute Adult Inpatient survey's seven dimensions of care are used to disseminate the patient data and focus the action plans. The areas with the largest problem scores and the highest correlation with overall satisfaction are identified, and then specific actions are devised to address those areas. For example, patient satisfaction data collected in May 1997 led the quality council to highlight information and education as an area for improvement for both inpatients and outpatients. Patients reported that they often got answers they could not understand. Also, they did not always get enough information at discharge to feel comfortable about going home. A Discharge/Transition Center CQI (continuous quality improvement) team was charged with developing a discharge/transition process that ensures continuity of care for patients as they move throughout the system. In addition, a hospitalwide Patient and Family Information team has been working on improving information delivery by developing both patient-friendly processes and useful educational materials. FUTURE DIRECTIONS: Harborview will continue to gather feedback through not only more targeted, specific surveys but also focus groups, which have been conducted around specific issues such as diabetes care, clinical pathways, pain management, and teen health.