Exam Cheat Sheet · Quick Reference

Arkansas Drywall - Commercial Exam

Arkansas  ·  PSI Services Contractor

Verified, not estimated. Every figure below is drawn from the official exam structure we maintain — question counts, passing standard and topic weighting. Practice questions are grounded in the source law with statute citations. We omit any figure we can't verify rather than guess at it.
Total questions
30
Passing score
70%
Exam time
75 min
Administered by
PSI Services Contractor
Format
Reference materials allowed

Arkansas State Portion 30 questions

Ceilings, Acoustical Systems Materials and Installation 8 Q · 27%
Suspension grid system types and components (main tees, cross tees, wall angle, hanger wire)Acoustical performance ratings (NRC, CAC, AC) and panel selection criteriaFire safety classifications and fire-rated ceiling assemblies (UL designs, ASTM E119)Step-by-step installation procedures for suspended acoustical ceilings (ASTM C635 and C636)Environmental and humidity considerations for ceiling system selection (ClimaPlus, exterior applications)Seismic compliance requirements for suspended ceiling systemsInterior finish flame spread and smoke-developed index classifications for ceiling materials (IBC Class A, B, C)Minimum ceiling height requirements and furred ceiling provisions (IBC Section 1208)
Drywall Materials and Installation 12 Q · 40%
Gypsum panel product types and specificationsFraming requirements for drywall systemsFastener types, spacing, and attachment methodsSingle-layer and double-layer application techniquesJoint treatment and finishing proceduresFire-resistance-rated assemblies and UL-listed designsBackerboard installation for wet areasCommon drywall defects, causes, and remedies
Taping and Finishing 4 Q · 13%
Special Applications Including Veneer Plaster 3 Q · 10%
OSHA Safety 3 Q · 10%

Key Distinctions

Sound Transmission Class (STC)vsImpact Insulation Class (IIC)

STC rates a partition's ability to attenuate sound passing through it, while IIC is a numerical evaluation of a floor-ceiling assembly's effectiveness in retarding transmission of impact sound (ASTM E492 testing, ASTM E989 rating).

Gypsum Construction Handbook (7th ed.), Chapter 10 — Fire and Sound Tests
Noise Reduction Coefficient (NRC)vsCeiling Attenuation Class (CAC)

NRC measures sound absorption, while CAC applies to ceilings between adjacent spaces.

Gypsum Construction Handbook (7th ed.), Chapter 10 — Fire and Sound Tests
ASTM E119vsASTM E90 / E413 / E492

ASTM E119 governs fire resistance testing of building construction and materials (also known as ANSI/UL 263 and NFPA 251), while E90 is sound transmission testing, E413 is STC rating, and E492 is impact sound testing.

Gypsum Construction Handbook (7th ed.), Chapter 10 — Fire and Sound Tests
UL Design U305 (one-hour, wood frame)vsUL Design U301 (two-hour, wood frame)

U305 uses a single layer of 5/8" Firecode core gypsum panels each side of wood 2×4 studs 16" o.c. with 1-7/8" cement-coated nails at 7" o.c. (insulation optional), while U301 uses two layers each side with base layer nailed 6" o.c. (1-7/8" nails) and face layer 8" o.c. (2-3/8" nails), face joints staggered over base joints.

Gypsum Construction Handbook (7th ed.), Chapter 10 — One-Hour Rating, UL Design U305
5/8" gypsum panel thicknessvs3/8" gypsum panel thickness

5/8" is recommended for the finest single-layer construction with increased resistance to fire and sound transmission, while 3/8" is recommended for repair and remodeling over existing surfaces.

Gypsum Construction Handbook (7th ed.), Chapter 2 Framing, Maximum Frame Spacing—Drywall Construction table, footnote (1)
Regular-core vs Type X vs Type C gypsum panels (1,850°F test)vs—

In the 1,850°F comparison test a 5/8" regular-core panel failed in 10 to 15 minutes, Type X lasted 45 to 60 minutes, and Type C lasted over 2 hours.

Gypsum Construction Handbook (7th ed.), Chapter 15 — Fire Resistance and Gypsum Panels section
Type W screws (1-1/4")vsType S oval head screws (1-1/4") / 8d nails

1-1/4" Type W screws attach resilient channels to wood studs (nails not recommended), while 1-1/4" Type S oval head screws or 8d nails attach steel runners to wood framing.

Gypsum Construction Handbook (7th ed.), Chapter 2 Framing, Resilient Channel Partitions section
Runners fastened to concrete/masonryvsRunners/fasteners for other substrates

Runners are attached to concrete and masonry with stub nails or power-driven fasteners, whereas toggle bolts are specified for suspended ceilings, Type W screws for wood framing, and Type S-12 pan head screws for foam-backed metal concrete inserts.

Gypsum Construction Handbook (7th ed.), Chapter 2 Framing, Runner Installation section
Hanger wire for residential suspended ceilingvsHanger wire for commercial suspended ceiling

The step-by-step suspended acoustical ceiling procedure specifies 18 ga. hanger wire for residential work and 12 ga. for commercial work, attached to lag screws or screw eyes set in joists.

Gypsum Construction Handbook (7th ed.), Chapter 9 — Step-By-Step Installation section
Ceiling control joints with perimeter reliefvsCeiling control joints without perimeter relief

With perimeter relief, control joints are required when ceiling dimensions exceed 50′ in either direction; without perimeter relief, control joints are needed when dimensions exceed 30′ (maximum 30′ intervals).

Gypsum Construction Handbook (7th ed.), Chapter 15 — Building Sciences, Control Joints section
Setting-type compound Durabond/Easy Sand 90vsSetting-type compound 210

Working time is usually 1 hour for 90-type setting compound and 2 hours for 210, so only as much as can be used in that period should be mixed.

Gypsum Construction Handbook (7th ed.), Cladding chapter, Mixing—USG Sheetrock Brand Setting-Type Compounds section
Benefit-cost analysis / initial construction costvsLife-cycle cost analysis

Life-cycle cost analysis considers the total cost of an assembly throughout its useful life including maintenance, rather than just initial construction cost or a budgeted figure.

Gypsum Construction Handbook (7th ed.), Chapter 10 — Selection of Materials
MCM alternate condition up to 50 feet in heightvsTable 1407.11.3.4 75-foot option

Under 2015 IBC 1407.11.2.2, MCM up to 50 feet above grade with self-ignition temperature of 650°F or greater is limited to sections not exceeding 300 sq ft separated not less than 4 feet vertically, while the smaller single-panel limits belong to the 75-foot option in Table 1407.11.3.4.

IBC 2015 Chapter 14 — Sections 1407.11.2 through 1407.11.2.2
Written emergency action planvsOrally communicated plan (10 or fewer employees)

Per §1926.35(e)(3), employers with 10 or fewer employees may communicate the emergency action plan orally and need not maintain a written plan.

OSHA 1926 CFR 29, §1926.35(e)(3)

Key Terms

Competent person (OSHA §1926.32(f)) OSHA 1926 CFR 29, §1926.32(f), Page 31
One who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them.
Impact Insulation Class (IIC) Gypsum Construction Handbook (7th ed.), Chapter 10 — Fire and Sound Tests
A numerical evaluation of a floor-ceiling assembly's effectiveness in retarding the transmission of impact sound, determined by ASTM E492 testing and rated per ASTM E989.
Sound Transmission Class (STC) Gypsum Construction Handbook (7th ed.), Chapter 10 — Fire and Sound Tests
A widely used rating of a partition's sound attenuation performance — its ability to attenuate sound passing through it.
Noise Reduction Coefficient (NRC) Gypsum Construction Handbook (7th ed.), Chapter 9 — Acoustical Ratings section
A sound absorption rating; an NRC of .50 or higher offers significant sound absorption, and panels engineered for increased acoustical performance are rated .70 or above.
ASTM E119 Gypsum Construction Handbook (7th ed.), Chapter 10 — Fire and Sound Tests
"Standard Test Methods for Fire Tests of Building Construction and Materials," the standard under which all fire resistance tests are conducted, also known as ANSI/UL 263 and NFPA 251.
Class A interior wall and ceiling finish (2015 IBC 803.1.1) IBC 2015 Section 803.1.1
A finish material with a flame spread index of 0–25 per ASTM E84/UL 723 (Class B = 26–75, Class C = 76–200).
Life-cycle cost analysis Gypsum Construction Handbook (7th ed.), Chapter 10 — Selection of Materials
An evaluation method considering the total cost of an assembly throughout its useful life, including maintenance, rather than initial construction cost alone.
Setting-type joint compound Gypsum Construction Handbook (7th ed.), Chapter 5 — Finishing Drywall Systems, — Setting-Type Joint Compounds System Applications, One-Day Finishing section
A joint compound that hardens chemically rather than by extended drying, recommended for one-day finishing when it sets within 1-1/2 to 2 hours.
Type C (Firecode C) gypsum panel Gypsum Construction Handbook (7th ed.), Chapter 15 — Fire Resistance and Gypsum Panels section
A panel containing a shrinkage-compensating additive — a form of vermiculite that expands with heat at about the same rate the gypsum core shrinks from water loss — giving dimensional stability during fire exposure.
UL Design U419 Gypsum Construction Handbook (7th ed.), Chapter 10 — One-Hour Rating, UL Design U419
A 1-hour rated steel stud drywall system using steel studs (362S125-18 minimum) at a maximum 24" o.c. with 5/8" Firecode core gypsum panels each side attached with Type S screws at 8" o.c.
UL Design U305 Gypsum Construction Handbook (7th ed.), Chapter 10 — One-Hour Rating, UL Design U305
A one-hour rated wood stud drywall system with 5/8" Firecode core gypsum panels each side of wood 2×4 studs 16" o.c. (insulation optional), nails at 7" o.c.
UL Design U301 Gypsum Construction Handbook (7th ed.), Chapter 10 — Two-Hour Rating, UL Design U301
A two-hour rated drywall system on wood framing with two layers of 5/8" Firecode core gypsum panel each side, face-layer joints staggered over base-layer joints.
UL fire design prefix "L" Gypsum Construction Handbook (7th ed.), Chapter 9 — Fire Safety section
A UL Fire Resistance Directory prefix identifying wood or combination wood and steel joist floor/ceiling assemblies (e.g., L202, L206).
Resilient channel (wood stud application) Gypsum Construction Handbook (7th ed.), Chapter 2 Framing, Resilient Channel Partitions section
A framing channel attached to wood studs with 1-1/4" Type W screws driven through the flanges; nails are not recommended.
Risers (gypsum board storage) Gypsum Construction Handbook (7th ed.), Chapter 11 — Handling and Storage
Supports under stored board, evenly spaced no more than 28 inches apart, within 2 inches of board ends, and placed directly under each other vertically to prevent sag, damage, or deformity.
Permissible noise exposure (OSHA §1926.52, Table D-2) OSHA 1926 CFR 29, §1926.52, Table D-2, Page 36
The maximum permissible noise exposure for an 8-hour duration is 90 dBA slow response.
Drywall suspension system panel attachment Gypsum Construction Handbook (7th ed.), Chapter 2 Framing, Gypsum Panel Installation section (Drywall Suspension System)
Gypsum panels attached with No. 6 Type S bugle head screws spaced 8" o.c. at the periphery and 12" o.c. in the field.

Formulas to Know

Gypsum board quantity takeoff for partitions with board on each sideTotal board SF = partition wall area × 2 sides (worked example: 12,000 SF of partition wall × 2 = 24,000 SF of 5/8" board)
Screw estimate, single-layer wall on 16" o.c. framingApproximately 1,000 screws per 1,000 SF of gypsum board (Type W for wood; Type S or S-12 for steel)
Interior non-load-bearing partition lateral design loadDesign for 5 psf lateral load; manufacturers' maximum allowable load tables start at 5 psf and increase in 5- or 10-psf increments to about 40 psf
Ceiling control joint spacingWith perimeter relief: control joints where ceiling dimension exceeds 50′ in either direction; without perimeter relief: control joints at maximum 30′ intervals
Curved partition runner cuttingCut one leg and the web of top and bottom steel runners at 2″ intervals for the length of the arc, leaving 12″ of uncut runner at each end
Toilet facilities required (OSHA Table D-1)20 or fewer employees = minimum 1 facility
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