|General's line of portable air blowers can accommodate
most nonhazardous confined space ventilation requirements. Select from 8"
to 12" diameter units with power choices of gasoline, diesel, 12 VDC or
115 VAC. Both radial and axial housing configurations are available for
the most demanding air flow applications.
Blowers are ideal for supplying fresh air around construction sites;
removing toxic and noxious atmospheres from confined work spaces;
detecting sewer line leaks and providing fresh air when working in tanks
and vaults. Proper ventilation increases safety and worker productivity
rates while conforming to tough federal and state OSHA regulations.
Each unit is designed to General's highest quality standards for
uncompromised utility and investment return. There are no plastic parts to
crack. Constructed with heavy-gauge aluminum and steel, all General
blowers offer laboratory certified air flow rates from independent, third
party, agency testing.
Breathe easier with a General blower on the job site... cost effective
solutions to confined space ventilation.
Duct Length/ Air Flow
Due to friction loss caused by air moving against the inside surface,
air flow rates decrease as duct lengths increase. For most 8" diameter
blowers, friction loss will usually limit the maximum practical duct
length to 25'. Configurations requiring additional duct length or drastic
directional changes can result in substantially lower air flow rates.
The 12" diameter Model EP12AC was specifically designed to overcome the
problems normally associated with longer duct lengths. The key factor is
the capacity differences between 8 inch and 12 inch diameter ducts.
Greater capacity means less friction loss. The EP12AC matches the power of
its motor against the high static capacity of the specially-designed
propeller. This combination enables the EP12AC to better overcome friction
losses and deliver higher air flow rates over longer duct lengths.
|The air flow rate, regardless of duct length, directly affects
the total number of times per hour the atmosphere within a confined
space can be properly recirculated. Federal OSHA regulations do not
specify minimum air flow standards for blowers or an air
recirculation requirement. However, many states have developed
individual air recirculation standards that directly affect the
final ventilation configuration, blower selection, duct length and
even the number of blowers required. Plan any confined space entry
by first determining the amount of air flow needed. Then choose the
best configuration of minimize duct length and the number of
directional changes. Selection of the proper ventilation will
deliver the performance needed to meet any atmospheric recirculation