7A Ch2 Cheat Sheet: Equipment in Pest Management

🎯 Top 5 Traps

1

Pressure does NOT proportionally increase flow rate — must increase pressure FOURFOLD to DOUBLE the flow. Doubling pressure does not double flow. The relationship is disproportional. Pressure can make minor flow adjustments; major changes require swapping the nozzle tip. The exam tests this directly.

2

Pressure ranges flip by application: CRACK & CREVICE = LESS THAN 10 PSI. FAN SPRAY = 20 to 25 PSI. Crack & crevice (pin-stream) needs low pressure for penetration without splash-back — 2 to 4 pump strokes on a 1-gallon sprayer. Fan spray (fine or coarse) needs 20 to 25 psi for uniform pattern — 9 to 11 strokes.

3

Fogging does NOT enter cracks, crevices, cabinets, or any dead-air spaces. Aerosol droplets float in air and contact only exposed insects on horizontal surfaces. Fogging is a SUPPLEMENTARY method, not a primary treatment. Increasing fogging frequency means the underlying pest population isn't being suppressed.

4

Travel speed and application rate are INVERSELY proportional — halve speed, double the rate. But for structural pest management this is LESS critical than for outdoor agriculture, because spray is normally applied on a percentage basis to the point of runoff. Still, maintain uniform walking speed.

5

The COARSE fan (50 degrees) delivers MORE spray per minute than the fine fan (80 degrees) — counterintuitive. At 20 psi: coarse fan = 14.08 oz/min, fine fan = 6.40 oz/min. The wider angle has the LARGER orifice. The exam tests "Which delivers the most at 20 psi?" — answer is the coarse fan, not the fine fan.

🔢 Numbers You Must Know

Number

What It Represents

1 to 2 gallons

Hand-held compressed-air sprayer "workhorse" capacity (full range 1/2 to 3 gallons); stainless steel preferred

2 to 5 gallons

Backpack sprayer tank capacity

over 100 gallons

Power sprayer tank capacity (gasoline or electric engine; 3/8 to 1/2 inch hose)

40 to 75 psi

Backpack sprayer working pressure (max up to 150 psi)

less than 10 psi

Effective pressure for crack and crevice treatment (2-4 pump strokes on full 1-gal sprayer)

20 to 25 psi

Effective pressure for fan spray applications (9-11 strokes on full 1-gal sprayer)

3/4 full

Maximum sprayer fill level — remaining 25 percent of space is for air pressure buildup

4x pressure = 2x flow

To double the flow rate, must increase pressure FOURFOLD. Disproportional relationship — pressure can only make minor flow adjustments; major changes require nozzle tip swap.

10 ft x 25 ft (250 sq ft)

Minimum suggested calibration test area for hand-held sprayer; multiply spray volume by 4 to get gallons per 1,000 sq ft

1 hour

If sprayer not used for an hour or more (e.g., over lunch), release pressure — hoses and gaskets deteriorate under prolonged pressure

60 percent

Estimated fraction of sprayers with up to 10 percent calibration error

🔀 Easily Confused

Pair / Group

Distinguishing Feature

Hand-held vs Backpack vs Power sprayer

Hand-held: 1-2 gal, low pressure, indoor C&C and flushing — "workhorse." Backpack: 2-5 gal, piston pump, 40-75 psi, larger indoor (warehouses, food facilities) and outdoor perimeters/lawns. Power: 100+ gal, gas/electric engine, termite control + outdoor perimeters.

Coarse fan (50 degrees) vs Fine fan (80 degrees)

Wider angle = LARGER orifice = MORE spray. Coarse fan: 14.08 oz/min @ 20 psi — outdoor foundation walls. Fine fan: 6.40 oz/min @ 20 psi — flea treatment on carpeting.

Pin stream vs Flat fan

Pin stream: solid stream — for cracks and crevices, deep penetration. Flat fan: even coverage on flat surfaces (walls); will not penetrate cracks as deeply as pin stream.

Crack & crevice extension tube

Plastic or metal tube fitted to a pin-stream nozzle. Allows direct C&C application with little spilling or splashing on surrounding surfaces.

Cold fogger vs Thermal fogger

Cold fogger: mechanical droplet generation; ULV/ULD; mosquito control + warehouses + flies. Thermal fogger: heat vaporizes oil-based formulation; smaller droplets; truck-mounted for mosquito; portable indoor units. Thermal fog can ignite — extinguish all open flames and pilot lights.

Aerosol vs Canned-pressurized liquid spray

Aerosol: fine droplets float in air; supplementary; doesn't reach cracks. Canned-pressurized liquid: NOT aerosols — coarse wet spray; with C&C nozzles can target precisely; little becomes airborne.

Bulb vs Bellows vs Plunger duster

Bulb: rubber bulb, removable spout, squeezed. Bellows (Getz): rubber cylinder with internal spring, top-and-bottom pressure. Plunger: high-impact plastic, holds more dust, multiple nozzle styles.

🚿 Sprayer Equipment Quick Reference

Sprayer Type

Capacity / Pressure

Best Use

Hand-held compressed-air

1/2 to 3 gal (typically 1-2 gal); stainless steel; low pressure preferred

Indoor crack & crevice, flushing agents, spot treatments — applies pin-stream and flat-fan patterns via 4-way multi-tip nozzle. The industry workhorse.

Backpack / Knapsack

2 to 5 gal; piston pump; 40 to 75 psi working (max 150 psi); flood jet or cone nozzles only

Larger indoor areas (warehouses, commercial food facilities); outdoor lawns, fences, building perimeters. NOT for precision low-pressure C&C.

Power sprayer

Over 100 gal; gasoline or electric engine; 3/8 to 1/2 in hose (length to reach pump-to-site)

Termite control AND building perimeters/lawns. Low pressure preferred outside (better penetration, no surface blast). Watch hose wear; carry spill pad.

📊 Nozzle Output @ 20 psi (Table 2-1)

Pattern

Spray Angle

Oz of spray / minute

Coarse fan

50 degrees

14.08 (highest output — exam answer for "most spray per minute")

Fine fan

80 degrees

6.40 (less than half the coarse fan despite the wider angle name)

Broad pin stream

Straight

8.96

Fine pin stream

Straight

4.48

Crack & crevice straw

Straight

3.84 (lowest — for precision injection into voids)

Aerosol-tip straw

Straight

7.04

💡 Memory Hooks

Pressure-flow ratio: "Four times the pressure for two times the flow." Disproportional relationship — pressure can only make minor adjustments. Major changes require nozzle tip swap.

Pressure ranges: "Under 10 for cracks; 20 to 25 for fans." Two pressure regimes for two application types.

Fill rule: "Three quarters full — leave a quarter for air." 25 percent air space is needed for pressurization.

Fogging limits: "Fogging fills the air, not the cracks." Aerosol droplets float — they contact exposed insects on horizontal surfaces only. Fogging is supplementary, never primary.

Coarse vs fine: "Coarse delivers more than fine — counterintuitive." 50-degree coarse fan = 14.08 oz/min vs 80-degree fine fan = 6.40 oz/min at 20 psi.

Ch.2: Equipment in Pest Management

🎯 Top 5 Traps

🔢 Numbers You Must Know

🔀 Easily Confused

🚿 Sprayer Equipment Quick Reference

📊 Nozzle Output @ 20 psi (Table 2-1)

💡 Memory Hooks