Comercial Air Filters And Sound Control Flashcards
Where do you put canvas connections on exhaust fans ?
Both sides
What should not be used in kitchen exhaust ducts or with airstreams conveying solids or corrosive gases ?
Ductbliner ( installation)
When velocity exceeds 4000 rpm what must be used for insulated duct ?
Insulation caps
In a building what is the primary noise source ?
Mechanical equitment
How many microns in one meter ?
One million
What do drift eliminators do ?
Can be installed to help control humidity problems
What are some options to attain proper noise reduction ?
Silencers
Fan isolation mounts
Interim bases
Fkexiabke connectors
acoustical liners and special sound traps
List four types of isolator options available for centrifugal fans
Free standing
Restrained spring
Housed spring
Rubber in shear and neoprene mounts
Are springs colour coded if so why
Yes to indicate the load capacity
What material is used on the interior of a silencer ?
Acoustic insulation and perforated metal
Where are flexiabke duct connectors used ?
Between machinery and ductwork
Can duct liners be used for a kitchen exhaust system ?
No
What is the amount of adhesive coverage required when installing duct liner ?
100% coverage
When is metal nosing used on a duct liner
When velocity exceeds 4000 fpm
What is the function of internal duct liner ?
For sound attenuation
When should filters be changed ?
When the resistance to airflow has increased to two times the original recommended replacment by the manufacturer
Are viscous impingement filters coated, if they are what is the coating ?
Yes with oily spray
What does the acronym merv stand for ?
Minimum efficiency reporting value
What is the name of the gauge used to measure the pressure differential across filters ?
The magnehelic gauge
Which type of filter is used for odours and gaseous contaminants ?
Activated carbon filters
Name two types of air washers ?
Spray type and cell type
Name two types of air washers ?
Spray type and cell type
Name two stages of an electronic air cleaner ?
Charging section
Collecting section
Which stage of an electronic air cleaner uses ionizing wires with positive charge ?
Charging section
What are two common methods of filter efficiency testing ?
Duct spot test
Weight test
An earthly matter smaller than 100 microns would describe
Dust
Filtering media of fiber screen wire mesh expanded metal stamping or plates coated with an oily substance would best describe ?
Viscous impingement filter
To be classified as a high efficiency filter a dry media filter must have a dust spot efficiency greater than ?
40%
A two stage precipitator is another name for a
Electronic air cleaner
The viscous impingement filter uses ______ effect to force the rapidly moving contaminant particles to strike the filter media
Centrifugal
The _____tes and the dust spot test are two methods of measuring dust concentration before and after the filter
Weight
Spray type air washers should never be installed on the suction side of the fan unless they have been built for this purpose
(True or false )
False
The more efficient type of air washer is ?
Cell type
The direct transmission of sound from one opening to another through ductwork itself would define ?
Cross talk
To improve arrestance some filters are coated with an adhesive this type of filter should be referred to as
A viscous impingement filter must
To prevent the vibration from a floor mounted fan from being transferred to the floor you could use
Rubber mounts
Allergy particles from weeds trees flowers and other forms of vegetation would describe ?
Pollen
Dry media air filters are most efficient at
Low air filtration velocity’s
Noise attenuation is important
On both sides of the duct system
Merv ratings are based on ?
Ashare std. 52.2
