A 2 × 2 replicated field intervention experiment was conducted in a call-centre providing a national public telephone directory service: outdoor air supply rate was adjusted to be 8 or 80% of the total airflow of 430 l/s (3.5 h-1); and the supply air filt
A new derivation of productivity calculation model based on pollution loads and contaminantremoval effectiveness is applied and the effect of the improved ventilation efficiency onproductivity is estimated. The findings show that the proportion dissatisfied could be asuitable predictor of productivity loss due to indoor air quality in different kinds of officework. The proportion dissatisfied is possible to calculate from olf and decipol units. In a caseof one person per 10 m2 (0.1 olf/m2) and low-emitted material (0.1 olf/m2), the total sensorypollution load is 0.2 olf/m2.
A method has been developed to investigate the comfort in office buildings. It is based onboth measurements and a questionnaire. The measurement apparatus, the so-calledAmbiometer, can record both the main comfort parameters, such as temperature, humidity,noise, light and odours, and the occupant's perceived comfort. Information regarding theindoor climate and the working environment is noted on the questionnaire.Experiments were conducted on about 50 offices in France.
A blind intervention study in which air temperature and the outside air supply rate were changed in a 2 × 2 design was carried out in a call centre in Singapore. The reported intensity of headache and difficulty in concentrating were reduced by 19.5% (P
The goal of the present study was to examine the influence of CO2 concentration in the air ofindoor spaces on human well-being and intensity of mental work. Ten experimental subjectswere used in four experimental conditions with different CO2 concentrations (600, 1500,3000, 4000 ppm). Microclimatic parameters (CO2 concentration, temperature and relativehumidity of the air, surface temperature of walls) were measured.
The impact of dry indoor air on comfort and health in winter was investigated in a crossoverintervention study in two floors of an office building in northern Sweden. The indoor airhumidity (normally 10-20% RH) was raised to 23-24% RH, one floor at a time, using steamhumidifiers. Questionnaires and objective (clinical) measurements were applied.
Ozone concentrations were monitored up- and downstream of used filter samples at airflowsof 1.0 and 0.2 l s-1. The ozone concentration in the air upstream of the filters was ~75 ppb,while the concentration downstream of the filter was initially ~35% lower at 1 l s-1 and ~55%lower at 0.2 l s- 1. Within an hour the removal efficiency had decreased to roughly 5% at1 l s- 1 and 10% at 0.2 l s- 1. These filter samples were then placed in either nitrogen or ambientair for 48 h. Afterwards it was found that there was partial regeneration of the filters ozoneremoval capabilities.
As part of a graduation project, a typical ‘sick’ office building was subject to a retrofit R&D programme. It concerned a typical 1975 building with a sealed façade and a central climate control system with induction units. An interview of the some of the
The first survey of the ‘French permanent survey on Indoor Air Quality’ will start in 2003 on a random sample of 710 dwellings. To optimize the study cost, a ranking method was developed for prioritizing 70 pollutants including chemical and biological age
This paper will review 6 years of experience in risk communication and meeting workplaceinformation needs about the health effects experienced by people working in sealed buildings.The purpose of this paper is to discuss examples of the kinds of information that theworkplace community is seeking and what answers can or cannot be provided.In the past two decades, there has been a growing concern about potential chronic healtheffects of poor indoor air quality and mould.