Measurement of total mass concentration

P

Samplingprobe

Vacuumpump

Flowregulator

Flowmeter

Pressure gauge

Filterholder

Filter

Screen

1. Sampling probe

- Isokinetic or sampling from still air

2. Flow rate

- Rotameter or digital flowmeter

3. Filter

- Nearly 100% efficiency for all size.- 13, 25, 37, 47 mm (circular).- 200 mm x 250 mm (Hi volume sampler).

4. Filter holder

- - Open face: uniorm distribution of particles for analysis in microscope.- - Closed face: simple, for mass concentration measurement.

Open-face Closed-face

5. Balance- Analytical balance, 0 .0 1 to 0 .1 mg sensitivity.- Electrobalance, 0 .1 to 1 0 g gggggggggggg- - Sample should be kept in the room with balance for 1 2

4hr ggggg ggggggggggg g6. Vacuum pump

- Personal pump; low flow rate 1-4 l/min.

- Larger pumps; 100 l/min.

Diaphragm pump Blower pump forHi-volume sampler

Calculation for mass concentration

mcQt

cis concentrationis total mass collectedis flow rateis sampling time

m

Q

tMinimum sampling volume

10SV

c

Vis sampling volume

is sensitivity of balanceis standard concentration

S

c

Personal sampler

- g ggg gg ggggggggggg ggggggg gg gggggggg g ggggggg gggggggg gg gggggggg- - 30Measuring in the breathing zone; with cm radius of workers’ mouth.- ggggggg ggg gggg ggg g ggg ggggggg gggggg ggggggg, .- -10Additional size selective option available; e.g. PM .

SKC personal sample.

SKC personal sampler taken apart.

High Volume sampler

- - - Using 2 or 3 stage centrifugal blower to pull air in.- : 1 7 0 0 / ( 6 0 ).- gggggggg ggggg g gggg gg gggg gg gggg gggggggg flow rate that may be affected by temperature and pressure change, or pressure drop due to dust loading on filter.- Used 200 mm x 250 mm (8 in x 10 in) glass fiber filter.- 50 30A roof with % for sampling of micron particle at wind speed of 8 km/hr.

PM-10 & PM-2.5

- Standard in analysis of atmospheric dust issued by the U. S. Environmental Protection Agency (EPA).

- 10Suspended particle smaller than micron in diameter.- Respirable; smaller particle travels deeper in respiratory tract.- Impactor or cyclone can be used to cut off particles greater than 10 micron.- - 24 hr average for 3 samplings in 3 years must not exceed 150 g/m3.- - 24 50Annual average for hr sampling must not exceed g/m3.

PM-10

- 25Suspended particle smaller than . micron in diameter.- For study of small aerosol particles thae affect visibility.- Particles smaller than 2 .5 microns usually composed of SO

4

-2 g NO3

-g NH4

+g and C.- gg gg ggg; , .- Organic compounds; Polyaromatic Hydrocarbons (PAH).

PM-2.5

Personal sampler for respirable dust- Using cyclone for size selection.- Flow rate of 1.9 l/min

PM-10 High Volume Sampler

- For sampling of suspended particles smaller than 10 micron.

PM-10/PM-2.5 Dichotomous Sampler

- Classifying particles in 2 size range; 10 micron and 2.5 micron.- Using virtual impactor.