Advanced Air Pollution Engineering Sampling
WHY TO SAMPLE THE AIR? TO KNOW: WHICH SUBSTANCE IS THE WORKER EXPOSED? HOW MUCH SUBSTANCE IS THE WORKER EXPOSED? WHEN DOES THE EXPOSURE HAPPEN? FORMS THE BASIS FOR PREVENTION MEASURES
HOW TO SMAPLE? SAMPLING STRATEGY WHAT TO SAMPLE? WHEN TO SAMPLE? HOW OFTEN TO SAMPLE?
HOW TO SAMPLE? BASIC STEPS OF SAMPLING STRATEGY DETERMINATION OF FACTORS AT THE WORK PLACE ESTIMATION OF LEVELS OF EXPOSURE How much a substance used or formed? How frequent the subsatance is used or formed? How long the workers use it or make it form?
HOW TO SAMPLE? BASIC STEPS OF SAMPLING STRATEGY MAKE A LIST OF POSSİBLE EXPOSURES PUT THE MOST POSSIBLLE AND/OR MOST DANGEROUS EXPOSURES FIRST IN THE LIST
HOW TO SAMPLE? MORE POINTS TO CONSIDER WHILE FORMING THE LIST BASIC STEPS OF SAMPLING STRATEGY MORE POINTS TO CONSIDER WHILE FORMING THE LIST THE DUTIES IN THE WORK WORK FORMAT AND TECHNIQUES PRODUCTION PROCESSES PHYSICAL CONDITIONS OF THE WORK PLACE SAFETY PRECAUTIONS AND OPERATIONS
HOW TO SAMPLE? MORE POINTS TO CONSIDER WHILE FORMING THE LIST BASIC STEPS OF SAMPLING STRATEGY MORE POINTS TO CONSIDER WHILE FORMING THE LIST AIR CONDITIONING AND OTHER ENGINEERING CONTROLS EMISSION SOURCES EXPOSURE DURATIONS WORKLOAD
HOW TO SAMPLE? REMARK 1 PERSONAL SAMPLING: NUMBER OF SAMPLES DETERMINE GROUPS ACCORDING TO EXPOSURE TYPES.(EX.: WELDERS, PAINTERS, TRANSPORT VEHILCE DRIVERS ETC.) CONSIDER THE HOMOGENITY OF GROUPS WITHIN THEIRSELVES IF HOMOGEN GROUPS: 1 SAMPLE FROM EVERY 10 WORKERS IF NON-HOMOGEN: INCREASE THE NUMBER OF SAMPLES
HOW TO SAMPLE? REMARK 2 STATIONARY SAMPLING: USE IT IF A WORKING ROOM IS VISITED OCCASIONALY (BATTERY CHARGE ROOM) A LOT OF WORKERS ENTER OR LEAVE THE WORKING ROOM IN WHICH A HIGH RANKED SUBSTANCE IN YOUR LIST EXSITS IN THE AIR (MANUAL LOADING OR DISLOADING OF A TRUCK)
HOW TO SAMPLE? REMARK 3 DO THE SAMPLING AS MUCH AS ALLOWS TECHNICAL MEANS COST TIME ALLOWS STARTING FROM THE BEGINING OF YOUR LIST
HOW LONG TO SAMPLE? THE TECHNICAL MEANS DICTAES THE DURATION OF A SINGLE AIR SAMPLE SUCH AS: CAPACITY OF FILTERS OR SORBENT TUBES CAPACITY OF PUMPS THE LIMITATIONS GIVEN IN THE STANDARD METHODS USED BUT!!!!
HOW LONG TO SAMPLE? Sampling Time Number of Min. Samples For Each Shift 10 seconds 30 1 minute 20 5 minutes 12 15 minutes 4 30 minutes 3 1 hour 2 ≥ 2 hours 1 IN ORDER TO REPRESENT AN 8 HOUR SHIFT
HOW LONG TO SAMPLE? IF THE WORKER DOES SEVERAL JOBS OR HAS LARGE INTERVALS BECAUSE OF ABSENCE OF TASK THEN: CALCULATE: ci: Occupational exposure concentartion (mg/m3 or ppm or etc.) ti: :Exposure time fo i’th job (hours) ∑ti:Sfift duration (Generally 8 hours)
VOLATILE ORGANIC GASES SAMPLING TECHNIQUES: ACTIVE CARBON SORBENT TUBES AND LOW FLOW SAMPLING PUMPS
FACTORS AFFECTING THE QUALITY OF VOC SAMPLES SELECTION OF LOCATION OR PERSON: GAS CONCENTRATION VARIATIONS ARE ESTIMATED USING TWO NUMBERS Reynolds Number Archimedes number
FACTORS AFFECTING THE QUALITY OF VOC SAMPLES As the Reynold's number incraese More homogenious distribution Lower exposure at the source As the Archimede's number increase, Movements towards the hot walls Lower average concentartions
Formaldehyde Samples Passive sampler filled with DNFH is used
Formaldehit Numunelerinin Kalitesini Etkileyen Faktörler Same factors with VOCS in terms of distribution and adsorbtion BUT! More sensitive to Reynold's and Archimede's numbers
FACTORS AFFECTING THE QUALITY OF FORMALDEHYDE SAMPLES BUT!: More sensitive to temperature WHY?: Its adsorbtion is more exothermic.
DUSTS THERE ARE TWO MAJOR TYPES WHE SAMPLING IS CONSIDERED Cyrstaline structure dusts Fibrous dusts
Cyristalline Structure Dusts High flow rate pumps are used for sampling these dusts Sidekick Deluxe
INHALABLE AND RESPIRABLE DUSTS Cyclone head for respirable dusts IOM head for inhalable dusts. Cyclone head IOM head
FACTORS AFFECTING THE QUALITY OF CYRSTALLINE DUST SAMPLES Reynold's number (more or less sensitive depending on the type of dust) Less sensitive to Archimede's number. WHY: Larger particles than gases which are hardly affected by bıuancy forces of air.
FACTORS AFFECTING THE QUALITY OF FIBROUS DUST SAMPLES Same factors with cyrstalline dusts Special Sampling heads are used Special preperation of filters before sampling Fibrous dust head