Download NAFA CAFS Exam: Contaminate Control and Air Filtration and more Exams Oil Engineering in PDF only on Docsity!
NAFA CAFS Exam | Actual Exam Questions |
100% Correct Answers | Verified
2024 Version
What are the 3 types of media used in contaminate control - ✔✔Active carbon, chemically treated carbon, potassium permanganate What is residence time? - ✔✔the time it takes air to cross a distance equal to the thickness of the filter without accounting for the resistance of the media through which it travels What are the variations of the contamination control principle - ✔✔clean the air required by the process, blanket the product with cleaned air, offer enough air flow to move contaminated air away from the product What is removal efficiency - ✔✔The fraction of the contaminate that once in contact with the media is removed by either physical or chemical means What is Capacity - ✔✔The amount the media is capable of removing - this determines the life of the filter What are two types of filter options - ✔✔partial bypass, total retention What is the ASHRAE standard 62.1/62.2 - ✔✔Ventilation for acceptable indoor air quality to specific minimum ventilation rates IAQ which will be acceptable to humans and are intended to avoid adverse health effects How many classifications of air is there? - ✔✔ 4 What are the IAQ testing applications - ✔✔Particulate contaminants, Gas phase, systems integrity, comfort parameters
What are the control strategies - ✔✔Filtration, source removal, Dilution Min demonstrated overspray filter eff must be at least - ✔✔98% What is the min eff for a Super ULPA - ✔✔99.9999% on MPPS What are the factors affecting ESP design and efficiency - ✔✔partical size, velocity through filter, voltage on ionizer and collector, collector plate spacing, collector plate loading, ionizer spacing and ozone What are the types of Microorganisms - ✔✔Virus, Bacteria, Fungi A baghouse is composed of - ✔✔house, hoppers, tubesheet and plenum A typical oil mist electrostatic presipitator has what sections (inlet to outlet) - ✔✔Baffle, ionizer, collecting, fan and optional after filter PCO has how many types of reactor configurations - ✔✔ 4 In the filter industry, a manometer is used to measure what? - ✔✔Pressure drop across the filter Airflow through a booth must be? - ✔✔high enough to keep the concentration of VOC vapor below 25% of its lowest explosive limit ULPA stands for? - ✔✔Ultimate low penetration Air Filter Name the components of a HEPA filter - ✔✔Media, separators, filter pack, sealant, framing, gasketing What size particles behave like a gas, have negligible settling rates and are affected by Brownian Motion - ✔✔Particals less than .1 microns
Why can't electronic air cleaners be tested for loading using the ASHRAE 52.2 test - ✔✔carbon in the dust shorts out the electrical connections VOC - ✔✔Volatile organic compound MPPS - ✔✔Most penetrating particulate size what are the factors that affect filter life - ✔✔partical size, underrating/overrating What is Chemisorption - ✔✔the result of chemical reactions on and in the surface of the absorbent What is the optimum final pressure drop - ✔✔the point where the sum of power cost & filter cost is at a minimum What is the total cost of filtration - ✔✔the sum of all first cost that can be depreciated..plus the sum of the annual operating cost UVGI - ✔✔Ultraviolet Germicidal Irradiation How does UVGI work? - ✔✔The DNA of the micro organisms absorb the UVGI energy - this breaks the DNA strand What are the types of PCO reactors - ✔✔coated wall annular design, packed bed, flat bed, box reactors Why capture aerosolized metal working fluids - ✔✔hazardous to people, may damage equip and facility, may be illegal to exhaust outside, can be reused What are the types of metal working fluids - ✔✔semi synthetic, synthetic, straight, soluble
mist and smoke removal is done with what type of filters - ✔✔media, centrifugal, electrostatic What are the Merv rating/color coded of lofted microglass media - ✔✔yellow=14, Pink=13, orange=11, tan 50= what is the function of ceiling diffusion media - ✔✔clean the air of particles 5 micron and larger, diffuse he air evenly across the booth Why do HVAC testing - ✔✔Determine efficiency of the particle size removal, amount of contaminate removed, and pressure drop What is the ANSI/ASHRAE 52.2 - 2012? - ✔✔A design qualification test, destructive test to measure merv, the test aerosol is Potassium Chloride .3 to 10 micron, dust loading aerosol to final pressure drop is the Ashrae standard dust test What is initial resistance - ✔✔Pressure required to move air through the filter at a certain air flow it written in inches, water or pascals HEPA filter testing consists of? - ✔✔Penetration converted to overall efficiency including gaskets, sealing and framing, initial resistance and 2 flow testing (leak test) What are the three ways to control molecular contaminants? - ✔✔Source control, ventilation/dilution, removal control What is straining? - ✔✔occurs when the smallest dimension of dust particle is greater than the distance between adjoining media fibers What 3 factors affect mechanical filter selection? - ✔✔efficiency, pressure drop, capacity What are the active charged media types? - ✔✔Triboelectric charging, corona charging, charging by induction
Particles bypass cells allow for retrofit without? - ✔✔large pressure increases in the system Name the three procedures for engineers to use in ASHRAE standard 62.1 - ✔✔Ventilation rate, indoor air quality, natural ventilation procedure Impingement filters are characterized by? - ✔✔Relatively high velocities and low pressure drop The four principles of air filtration are? - ✔✔Impingement, interception, diffusion, and straining The velocity of the air through any one square foot of media in an extended surface filter is called? - ✔✔Media velocity What percent of the total cost of a filter is energy cost? - ✔✔81% UVGI is most effective on micro organism in what range of the light spectrum - ✔✔200 to 280 nanometers What are vapors? - ✔✔Gases formed by evaporation of materials that are normally a liquid or solid What are the principles of air flow? - ✔✔Quantity of Air(Q) the velocity of air (V)and the area of the filter (A) What is pressure drop? - ✔✔the resistance a filter adds to the system What are the principles of Particulate Air Filtration - ✔✔Mechanical, electrostatically charged media, electronic air cleaners What is Diffusion? - ✔✔explains the capture of very small particles (Brownian Motion - the erratic path taken by very small particles because they are bombarded by other particles) This erratic path ncreases the probability that the particles will come into contact with the fibers
Dust separation is used for two objectives? - ✔✔Recover valuable product from plant processes that generate dust 2. Clean air to stay in compliance with OSHA and EPA requirements What is Aerosol? - ✔✔An assemblage of small particles, solid or liquid suspended in air What is Absorption? - ✔✔the process by which a liquid or a gas is taken into the interstices of a porous substance and held there What is Adsorption - ✔✔the process by which gas molecules adhere to surfaces - the strength of the bond depends on the van der waal forces between the gas and the surface What is Gas? - ✔✔Any material that has the tendency to expand indefinitely and which completely and uniformly fills the container it occupies A PCO advantage is it's? - ✔✔reaction at ambient temperatures/small addition of resistance to the HVAC system/complete destruction of a contaminant into harmless elements Humidity can hinder? - ✔✔Adsorption When does Interception occur? - ✔✔When a dust particle follows air streams but still comes into contact with the fiber as it passes around it. It is fiber size dependent and is enhanced when fiber and particles are close in size What does the effectiveness of impingements filters depend on? - ✔✔Dust particle size, density of the dust, depth of the filter, velocity of the airflow Impingement filters work by? - ✔✔larger particles do not move around the fiber with the airstream and are carried into the fiber due to their speed, weight and size What are the categories of enclosed finishing booths - ✔✔cross draft and down draft
what should technicians do before servicing units in which UV lights have been installed? - ✔✔Turn off the lights prior to opening compartments where the lights are located Why should UVGI lights be installed downstream of filters? - ✔✔UV light can destroy certain types of filter media Running filters to their maximum pressure drop may? - ✔✔cost more in energy than the cost to change it sooner Fan efficiency, drive efficiency and motor efficiency calculate into what cost? - ✔✔energy cost A major source of pollution in a building is? - ✔✔people Tuberculosis patients must be kept in rooms that are? - ✔✔Negative pressure to the other rooms Testing HEPA filters after installation is called? - ✔✔In-place leak testing or cold DOP test If static pressure goes up, velocity pressure goes? - ✔✔Down Metal working fluids are used to? - ✔✔cool, lubricate and clean production parts What are the two general categories of Enclosed Finish Booths? - ✔✔cross draft and down draft Name for issue when a person comes into a building and experiences flu-like symptoms? - ✔✔sick building syndrome Healthcare facilities follow filter guidelines of? - ✔✔American Institute of Architects (AIA) Bacteria reproduce by - ✔✔cell division
Even though smaller than 0.3 microns HEPA filters can remove? - ✔✔viruses Filter efficiency is best determined by a (n) - ✔✔Independant laboratory ANSI/ASHRA 52.2 test An electronic air cleaner collects particles by? - ✔✔Electrostatically charging them and collecting them on oppositely charges plates 1 millionth of a meter call a? - ✔✔Micron The air we breath is composed mainly of? - ✔✔Nitrogen The size of the particles in outdoor air are mainly what size? - ✔✔1 micrometer Rated flow of air through a filter at specifies pressure drop is called its? - ✔✔Capacity
