Kentucky Category 12 – Wood Treatment
Examination Questions And Correct
Answers (Verified Answers) Plus Rationales
2026 Q&A | Instant Download Pdf
1. What is the primary purpose of wood preservative treatments?
A. To change the color of wood
B. To improve the aesthetic appearance
C. To prevent decay, insect damage, and fungal attack
D. To make wood waterproof
Rationale: Wood preservatives are primarily applied to protect wood
from biological deterioration, including decay fungi, termites, and
other wood-destroying insects, rather than for aesthetic purposes.
2. Which type of wood is most susceptible to decay?
A. Heartwood of cedar
B. Sapwood of pine
, C. Teak wood
D. Redwood heartwood
Rationale: Sapwood contains more nutrients and moisture, making it
highly susceptible to decay, whereas heartwood and naturally
resistant species like cedar and redwood are more durable.
3. Which chemical is commonly used in pressure-treated wood to
prevent termite infestation?
A. Boric acid
B. Copper azole
C. Linseed oil
D. Sodium hydroxide
Rationale: Copper azole is widely used in pressure treatment to
protect wood from termites and fungal decay. Borates are used for
interior treatments, but not typically for exterior, ground-contact
wood.
4. What is the main difference between above-ground and ground-
contact treated wood?
A. Color of the wood
B. Retention level of preservative chemicals
C. Species of wood used
D. Moisture content
,Rationale: Ground-contact wood requires higher preservative
retention levels because it is exposed to moisture and soil organisms,
increasing the risk of decay and insect damage.
5. Which type of preservative is considered environmentally safer for
residential use?
A. Pentachlorophenol
B. Creosote
C. Boron-based preservatives
D. Arsenic-based compounds
Rationale: Boron compounds are low-toxicity preservatives suitable
for indoor use, unlike arsenic, creosote, or pentachlorophenol, which
are toxic and generally restricted to industrial applications.
6. How does pressure treatment protect wood?
A. By painting a protective layer on the surface
B. By forcing preservatives deep into the wood fibers under
pressure
C. By drying wood to reduce moisture content
D. By sealing the wood in plastic
Rationale: Pressure treatment uses a vacuum and pressure process to
impregnate wood with preservatives, providing long-term protection
against decay and insects.
, 7. Which of the following preservatives is primarily used for
industrial applications rather than residential?
A. Borates
B. Copper azole
C. Creosote
D. Alkaline copper quaternary
Rationale: Creosote is highly toxic and is mainly used for railroad ties,
utility poles, and marine pilings, not for residential applications.
8. Which wood species is naturally resistant to decay without
chemical treatment?
A. Pine sapwood
B. Poplar
C. Cedar heartwood
D. Maple sapwood
Rationale: Cedar heartwood contains natural oils that deter insects
and fungal growth, making it highly durable even without chemical
preservatives.
9. What is the function of chromated copper arsenate (CCA) in wood
treatment?
A. To improve wood flexibility
B. To prevent decay and insect damage
Examination Questions And Correct
Answers (Verified Answers) Plus Rationales
2026 Q&A | Instant Download Pdf
1. What is the primary purpose of wood preservative treatments?
A. To change the color of wood
B. To improve the aesthetic appearance
C. To prevent decay, insect damage, and fungal attack
D. To make wood waterproof
Rationale: Wood preservatives are primarily applied to protect wood
from biological deterioration, including decay fungi, termites, and
other wood-destroying insects, rather than for aesthetic purposes.
2. Which type of wood is most susceptible to decay?
A. Heartwood of cedar
B. Sapwood of pine
, C. Teak wood
D. Redwood heartwood
Rationale: Sapwood contains more nutrients and moisture, making it
highly susceptible to decay, whereas heartwood and naturally
resistant species like cedar and redwood are more durable.
3. Which chemical is commonly used in pressure-treated wood to
prevent termite infestation?
A. Boric acid
B. Copper azole
C. Linseed oil
D. Sodium hydroxide
Rationale: Copper azole is widely used in pressure treatment to
protect wood from termites and fungal decay. Borates are used for
interior treatments, but not typically for exterior, ground-contact
wood.
4. What is the main difference between above-ground and ground-
contact treated wood?
A. Color of the wood
B. Retention level of preservative chemicals
C. Species of wood used
D. Moisture content
,Rationale: Ground-contact wood requires higher preservative
retention levels because it is exposed to moisture and soil organisms,
increasing the risk of decay and insect damage.
5. Which type of preservative is considered environmentally safer for
residential use?
A. Pentachlorophenol
B. Creosote
C. Boron-based preservatives
D. Arsenic-based compounds
Rationale: Boron compounds are low-toxicity preservatives suitable
for indoor use, unlike arsenic, creosote, or pentachlorophenol, which
are toxic and generally restricted to industrial applications.
6. How does pressure treatment protect wood?
A. By painting a protective layer on the surface
B. By forcing preservatives deep into the wood fibers under
pressure
C. By drying wood to reduce moisture content
D. By sealing the wood in plastic
Rationale: Pressure treatment uses a vacuum and pressure process to
impregnate wood with preservatives, providing long-term protection
against decay and insects.
, 7. Which of the following preservatives is primarily used for
industrial applications rather than residential?
A. Borates
B. Copper azole
C. Creosote
D. Alkaline copper quaternary
Rationale: Creosote is highly toxic and is mainly used for railroad ties,
utility poles, and marine pilings, not for residential applications.
8. Which wood species is naturally resistant to decay without
chemical treatment?
A. Pine sapwood
B. Poplar
C. Cedar heartwood
D. Maple sapwood
Rationale: Cedar heartwood contains natural oils that deter insects
and fungal growth, making it highly durable even without chemical
preservatives.
9. What is the function of chromated copper arsenate (CCA) in wood
treatment?
A. To improve wood flexibility
B. To prevent decay and insect damage
