General Pest (7a), Structural Pest (7b), Fumigation (7c)
General Pest (7a)
Household and nuisance pests
General pest work covers the everyday invaders of structures and their immediate surroundings - ants, cockroaches, spiders, wasps, pantry pests, mice, and rats - but not wood-destroying organisms.
Core tools. Crack-and-crevice application, spot treatment, gel and granular baits, dusts in voids, and exclusion. Sanitation and moisture repair come before chemistry. Baiting is preferred where children, pets, or sensitive occupants are present.
Label constraints. Directions usually limit where you may apply: baseboards, cracks, voids, plumbing penetrations, and perimeters. Broadcast application of most indoor products is prohibited, and food-handling areas have their own rules: applications must not contact food, food-contact surfaces, or utensils, and some labels allow only crack-and-crevice work in those spaces.
Rodenticides. Second-generation anticoagulants carry strict placement, quantity, and tamper-resistant bait station requirements. Record placement and monitor stations.
Traps that trip candidates. Reading a product labeled for outdoor perimeter use as if it were an indoor product; assuming a general pest product also covers termites; ignoring the "not for use in food handling establishments" statement; and applying to a site not listed at all.
Worked example. German cockroaches in a commercial kitchen: gel bait in cracks and hinges, monitoring stations, and sanitation recommendations. A residual spray along baseboards is not the answer in a food area and may violate the label.
Structural Pest (7b)
Wood-destroying organisms
Structural pest control centers on termites, carpenter ants, wood-boring beetles, carpenter bees, and wood-decay fungi, plus wood-destroying organism (WDO) inspections.
Termite types. Subterranean termites nest in soil and build tubes to wood, so treatment is a soil barrier or a bait system. Drywood termites live inside the wood and require injection, foam, or fumigation. Know which describes the job before choosing a product.
Liquid barrier math. Termiticide labels specify dilution and application volume per linear foot per foot of depth, plus a volume per square foot for trenching and rodding. Hollow-block foundations, piers, and bath traps get extra volume. Overapplication is a label violation and a runoff risk; underapplication voids the warranty.
Inspections. A proper WDO report documents visible evidence, inaccessible areas, and conditions conducive to infestation. Never report a treatment you did not perform.
Traps. Confusing carpenter ants (which tunnel wood but do not eat it) with termites; treating a slab building as if it had a crawlspace; forgetting that baits and liquid barriers are not interchangeable; and skipping the label's retreatment interval.
Worked example. A 60-foot exterior trench, 3 feet deep, at 4 gallons per 10 linear feet per foot of depth: 60 ÷ 10 = 6 units × 3 feet = 18 units × 4 gallons = 72 gallons for the trench, plus interior and hollow-block volumes from the label.
Fumigation (7c)
Structural, commodity, and soil fumigation
Fumigants are gases that penetrate the treated space. They are the most hazardous pesticides an applicator can handle, so the exam emphasizes sealing, monitoring, placarding, and entry control more than pest biology.
Products. Sulfuryl fluoride for structural and commodity work, methyl bromide where still registered, phosphine from metal phosphide tablets for grain and burrowing pests, chloropicrin as a warning agent or soil fumigant, and metam sodium for soil.
Core requirements. Seal the space properly - tarps, tape, and sealing of vents. Post placards at every entrance. Control access for the entire exposure period. Use monitoring devices and instruments because the most common structural fumigant is odorless. Never enter without appropriate respiratory protection, and never work alone. Aeration must be verified with a calibrated device before reentry; the acceptable clearance level comes from the label, not from a guess.
Phosphine specifics. Metal phosphides release hydrogen phosphide on contact with moisture, are highly toxic, and are restricted-use. Fumigation of grain requires sealed structures and careful monitoring, and spent residue disposal follows the label.
Buffers and notification. Fumigant labels set buffer zones and notification requirements for nearby occupants.
Trap: the odor of a warning agent is not a safety guarantee, and a monitor reading at one point does not clear an entire structure.
Worked example. After a structural fumigation, sample at multiple points until each reads below the label clearance level; only then remove placards and allow reentry.