Indoor and Built Environment

In a study in Sydney, Australia, exposure to environmental tobacco smoke (ETS) particles and respirable suspended particles (RSP) for 319 self-reported non-smokers was assessed by personal monitoring. The subjects were sepa rated into four distinct groups for investigation: Home, Work, Elsewhere, and 24-Hour, which were further sub-divided based on whether they lived or worked with smokers. Saliva samples for cotinine analysis were taken at the start and end of each monitoring session. Good correlations (R2 > 0.86) were found between the three methods used in this study to assess the contribution of ETS particles to RSP from all sources. Annual exposure estimates for ETS particles and nicotine in smoking homes were greater than in smoking work places. Median annual exposure in smoking homes and workplaces equates to less than 4 cigarette equivalents per year (CE·y^-1). Exposures in non-smoking homes, non-smoking workplaces and away from the home and workplace were below the limit of quantification for most subjects. Based on the 90th percen tile, the highest exposed subjects would potentially inhale no more than 15 CE·y^-1. Subjects living with smokers had greater ETS exposure while away from home and work compared to subjects living with non-smokers. This Else where group were also exposed to the highest RSP concentrations. Question naire data indicated that subjects consider bars/restaurants to be the locations where they are exposed to most ETS in their daily lives. However, 62% of these subjects considered their exposure in these locations to be 'none' or 'very low' during the monitoring period. Saliva cotinine determinations would appear to be a good marker for evaluation of ETS exposure at 90th percentile levels. Out of 331 subjects recruited as non-smokers, 6 (1.8%) misreported their non-smoking status as demonstrated by their saliva cotinine level.

Indoor plantings are widely used in building environments though little is known regarding the way office workers respond to indoor foliage plants. The objective of the present study was to assess the effect of foliage plants in the office on health and symptoms of discomfort among office personnel. A cross over study with randomised period order was conducted; one period with plants in the office and one period without. A questionnaire consisting of 12 questions related to neuropsychological symptoms, mucous membrane symp toms and skin symptoms was distributed among the 51 healthy subjects who participated in the study. It was found that the score sum of symptoms was 23% lower during the period when subjects had plants in their offices com pared to the control period. (Mean score sum was 7.1 during the period with out plants vs. 5.6 during the period with plants.) Complaints regarding cough and fatigue were reduced by 37 and 30%, respectively, if the offices contained plants. The self-reported level of dry/hoarse throat and dry/itching facial skin each decreased approximately 23% when plants were present. Overall, a sig nificant reduction was obtained in neuropsychological symptoms and mucous membrane symptoms, while skin symptoms seemed to be unaffected by the presence of plants. The results from this study suggest that an improvement in health and a reduction in symptoms of discomfort may be obtained after intro duction of foliage plants into the office environment.

An evaluation of airborne lead exposure was conducted during abatement of a building as part of its demolition. Personal airborne exposure concentrations were collected over 29 working days. These results suggest, for this study, that exposure levels are highly variable, exhibit a nonnormal distribution and fre quently exceed the Occupational Safety and Health Administration Permissi ble Exposure Limit for lead. Various engineering and work practice controls were employed during this project to reduce exposure levels, although the con tractor did at times employ prohibited practices. Exposure results from this study suggest that lead abatement workers involved in demolition are not a homogenous group for sampling purposes. Studies are needed to evaluate engineering controls, work practices and worker exposure to airborne lead during abatement of buildings that are being demolished.

The successful application of moisture simulation models to building enve lopes requires accurate values of material permeability. Unfortunately, al though the presently available database is reasonably voluminous, much of the information contained therein is of limited use in such applications. This paper describes the specification of permeability data in terms of the differ ential permeability function. Several alternative mathematical forms are com pared using experimental results from a representative range of building mate rials and the most appropriate form is identified. The use of this function allows the accurate evaluation of permeability appropriate to the humidity conditions to which a material is subjected in practice. On the basis of theoret ical analysis, it is also suggested that this function allows the separation of the total moisture flux into its vapour and liquid components. This hypothesis has been tested for two materials using a prototype experimental procedure in which permeability measurements are made under different barometric pres sures.

Environmental conditions and energy use were evaluated in a new segregated early weaning (SEW) swine nursery for 9 months. Energy use and air quality were generally acceptable and followed expected trends. Mean electricity use ranged from 27 to 32 kWh.day ^-1. Mean fuel gas use ranged from 30 to 40 m³ natural gas·day ^-1. Ranges for total, respirable, and inhalable dust concentra tions were 0.50-3.13, 0.03-0.40, and 0.18-2.98 mg·m^-3, respectively. Carbon dioxide concentrations ranged from 1,144 to 2,614 ppm. Ammonia concentra tion was negligible (< 1 ppm) throughout the study.

Interim results are presented from a long-term German project investigating the effects of indoor climate and indoor air quality on the health, performance and well-being of more than 3,000 office workers. The ProKlimA project started in February 1995 with the aim of gaining insight into the phenomeno logy and aetiology of the so-called 'sick building syndrome' (SBS). One of the main findings from the project is that SBS-associated symptoms are experi enced in both air-conditioned and naturally ventilated buildings. However in air-conditioned buildings the level of symptoms reported is greater and seems to depend on the quality of maintenance.