Handbook of Radon.
44. The abstracts that never were. September 1990.
In August 1990, when working for BRE, the author visited Canada and the USA to study radon and radon remediation. Tentative arrangements were made to present one or more papers at the April 1991 EPA symposium in Philadelphia. Upon return to the UK three research abstracts were dispatched.
All three were accepted. The symposium schedules were printed and distributed to registered delegates, and included these papers. Later, the papers were ordered to be withdrawn. The abstracts should have been available under the US Freedom of Information Act, but were destroyed by the EPA. Therefore, brief summaries are all that can be reproduced.
Field comparison of Alpha-track detectors from the UK and USA
Various types of alpha-track (track-etch) detectors were exposed for the same periods of time in dozens of houses. The work is amongst the first in which results from sets of track-etch detectors from several suppliers and from various countries have been compared after use in buildings. Most comparisons have been laboratory based.
Initially, three types of detectors from the UK were exposed for around three months. One of each was placed in each of 40 rooms in various houses. Two types from the USA and one from the UK were included in later work. A total of over 200 detectors was used. Exposures ranged from background to about 20,000 kBq.h/m3, with exposure times from 1000 to 2500 hours. No account was taken of background counts, nor were control blanks used. The detectors were all used exactly as if they had been supplied to householders.
The results show large random and systematic differences between different detectors, sometimes of several hundred percent. The systematic errors were ascribed to:
(a) Use of detectors stored for months before use
(b) Differences in processing techniques between different laboratories
(c) Errors of calibration at low exposures.
Likely explanations are discussed, and recommendations made for better quality assurance.
Experience with radon proofing of new houses in the UK
In June 1988 the UK Government required that all new houses approved for construction after that date in delineated areas of the UK should be built incorporating radon protection measures. These requirements, given as suggested design solutions for achieving radon protection, were contained in 'Interim Guidance under Part C of the Building Regulations, Protection against Radon, June 1988'.
Initial assessments of the effectiveness of the guidance has been undertaken.
Radon levels in 140 new houses in radon prone areas of the UK were measured over three winter months using alpha-track detectors. Thirty-nine of these houses had been built with radon proofing, whilst the remainder had been built earlier and before the new design requirements.
Initial results are inconclusive but in houses built on relatively low activity sites, the measures have made no difference to indoor radon levels.
The selection and performance of radon remedial measures in UK housing
As part of the UK Government's response to the discovery of high radon levels in certain areas of the country, BRE has undertaken field trials of radon remedial measures in a selection of high-level houses.
A substantial body of information on how householders react to the discovery of high radon levels has been obtained. This is discussed. Simple remediation measures have proved popular, especially where these can have a good chance of success.
Details are given of the installation and performance of a number of remediation measures including simple sealing, house pressurisation and sub-floor ventilation. Results are presented from some of the houses but are variable in many. Therefore, care has to be exercised in claiming success.
UK high level houses cannot be characterised by a fixed radon level since even average levels can be influenced by use of the house.