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Measurement of wind speeds in indoor workplaces
230
Abstracts
EMISSION
AND DISPERSION FROM
OF SUSPENDED PARTICULATE MOTOR VEHICLES
MATTER
R. B. Singh and J. J. Colls Environmental
Science, University of Nottingham, Sutton Bonington Leicestershire. LE 12 5RD, U.K.
Campus.
Loughborough.
In this paper, a model is described for the calculation of motor vehicle particulate emissions both as total suspended particulate matter and within four size range> between 10 and 1 Atm. PMFAC calculates the emission factors from a road on a lane-by-lane basis and for available vehicle fleet structure data based on direct observations, closed circuit television records or average values of the country or region, including the emissions in user-defined elements of the lane near intersection. Then a dispersion model (PMLINE). which is a combination of modified CALINE4 and CPBM. is discussed. PMFAC is validated in a range of traffic and meteorological conditions in conjunction with PMLINE for PM10 and PM2.5 in urban (Loughborough in Leicestershire) and rural (A453 in Nottinghamshire) areas.
WIND TUNNEL MEASUREMENTS OF THE PHYSICAL SAMPLING EFFICIENCIES OF HIGH VOLUME VIRTUAL IMPACTORS AND CYCLONE SAMPLERS J. M. Clark.
S. R. Preston
CBD Porton
Down.
and D. Shakeshaft
Salisbury,
SP4 OJQ. U.K
Following the success of initial investigations. measurements of the physical sampling efficiency of two designs of High Volume Aerosol Concentrators and two nominally identical wetted walled cyclones have been made under controlled wind tunnel conditions. The wind tunnel investigation was carried out for wind speeds in the range aerosols of sodium fluorescein in the size range 1.5-I 2 btrn aerodynamic I~lOm s- I. using spherical, monodisperse diameter. The function of these collectors is to sample the atmospheric aerosol and separate the suspended particles from the air and place them into liquid suspension for subsequent analysis. The collectors were assessed on two aspects of their performance, their sampling efficiency and the concentration gain they achieve in transferring particles from air to liquid suspension. These two performance factors are vital for the effective use of these collectors. it is therefore important to balance both when assessing these instruments. The results highlight the importance of understanding the sampling performance of aerosol monitoring equipment if measurements made in the field are to be interpreted correctly. They also show that certain features of sampling equipment behaviour can only be identified through thorough testing under controlled laboratory conditions.
MEASUREMENT
OF WIND
SPEEDS
P. E. J. Baldwin Health
and Safety Laboratory,
IN INDOOR
WORKPLACES
and A. D. Maynard Broad
Lane, Sheffield. S3 7HQ, U.K
The inhalable convention. describing particle penetration into the respiratory tract, is based on measurements made using breathing manikins in wind tunnels with wind speeds between 1 and 5 m s .- ‘. However, previous limited surveys of workplaces have indicated that typical indoor wind speeds are below 0.3 msY’. We have carried out a number of indoor wind speed surveys at 27 different sites covering a range of industries. Measurements were made using static hot wire anemometers. A limited number of measurements were also made comparing readings from a static anemometer and one mounted on a person’s head. These comparisons showed that although wind speeds were higher in the vicinity of the person’s head compared to those measured by the static anemometer, the difference was only of the order of 0.1 rns- ‘. The pooled data from the static anemometer measurements showed wind speeds to be below 0.2 m s ’for the majority of the time, and significantly below this for much of the time. From our results and previously published data the indication is that 0.3ms-’ is a reasonable estimate for the upper wind speed in the majority of indoor workplaces away from high localised air flows.
Abstracts
EMISSION
AND DISPERSION FROM
OF SUSPENDED PARTICULATE MOTOR VEHICLES
MATTER
R. B. Singh and J. J. Colls Environmental
Science, University of Nottingham, Sutton Bonington Leicestershire. LE 12 5RD, U.K.
Campus.
Loughborough.
In this paper, a model is described for the calculation of motor vehicle particulate emissions both as total suspended particulate matter and within four size range> between 10 and 1 Atm. PMFAC calculates the emission factors from a road on a lane-by-lane basis and for available vehicle fleet structure data based on direct observations, closed circuit television records or average values of the country or region, including the emissions in user-defined elements of the lane near intersection. Then a dispersion model (PMLINE). which is a combination of modified CALINE4 and CPBM. is discussed. PMFAC is validated in a range of traffic and meteorological conditions in conjunction with PMLINE for PM10 and PM2.5 in urban (Loughborough in Leicestershire) and rural (A453 in Nottinghamshire) areas.
WIND TUNNEL MEASUREMENTS OF THE PHYSICAL SAMPLING EFFICIENCIES OF HIGH VOLUME VIRTUAL IMPACTORS AND CYCLONE SAMPLERS J. M. Clark.
S. R. Preston
CBD Porton
Down.
and D. Shakeshaft
Salisbury,
SP4 OJQ. U.K
Following the success of initial investigations. measurements of the physical sampling efficiency of two designs of High Volume Aerosol Concentrators and two nominally identical wetted walled cyclones have been made under controlled wind tunnel conditions. The wind tunnel investigation was carried out for wind speeds in the range aerosols of sodium fluorescein in the size range 1.5-I 2 btrn aerodynamic I~lOm s- I. using spherical, monodisperse diameter. The function of these collectors is to sample the atmospheric aerosol and separate the suspended particles from the air and place them into liquid suspension for subsequent analysis. The collectors were assessed on two aspects of their performance, their sampling efficiency and the concentration gain they achieve in transferring particles from air to liquid suspension. These two performance factors are vital for the effective use of these collectors. it is therefore important to balance both when assessing these instruments. The results highlight the importance of understanding the sampling performance of aerosol monitoring equipment if measurements made in the field are to be interpreted correctly. They also show that certain features of sampling equipment behaviour can only be identified through thorough testing under controlled laboratory conditions.
MEASUREMENT
OF WIND
SPEEDS
P. E. J. Baldwin Health
and Safety Laboratory,
IN INDOOR
WORKPLACES
and A. D. Maynard Broad
Lane, Sheffield. S3 7HQ, U.K
The inhalable convention. describing particle penetration into the respiratory tract, is based on measurements made using breathing manikins in wind tunnels with wind speeds between 1 and 5 m s .- ‘. However, previous limited surveys of workplaces have indicated that typical indoor wind speeds are below 0.3 msY’. We have carried out a number of indoor wind speed surveys at 27 different sites covering a range of industries. Measurements were made using static hot wire anemometers. A limited number of measurements were also made comparing readings from a static anemometer and one mounted on a person’s head. These comparisons showed that although wind speeds were higher in the vicinity of the person’s head compared to those measured by the static anemometer, the difference was only of the order of 0.1 rns- ‘. The pooled data from the static anemometer measurements showed wind speeds to be below 0.2 m s ’for the majority of the time, and significantly below this for much of the time. From our results and previously published data the indication is that 0.3ms-’ is a reasonable estimate for the upper wind speed in the majority of indoor workplaces away from high localised air flows.