Class A Fire Protection for Wood
Class A fire protection that preserves the natural beauty of wood — clear-drying, non-toxic chemistry for interior framing, exterior assemblies, and wood components.
CitroTech-34 (MFB-34) is a Class A fire inhibitor for wood, engineered to enhance ignition resistance without affecting the natural look, feel, or structural properties of lumber. The formula dries clear, is non-toxic, low-VOC, and suitable for both interior and exterior assemblies.
Meets ASTM E84 requirements for flame spread and smoke development.
Maintains the natural appearance and grain of treated wood.
No PFAS, no halogens, and GREENGUARD Gold–recognized ingredients.
Designed for long-term performance in framing and finish applications.
Performance Data
ASTM E84
(Surface Burning)
Measures flame spread and smoke development on treated wood.
Class A Rating
ASTM E84
(Surface Burning)
Measures flame spread and smoke development on treated wood.
Class A Rating
ASTM E2768
(Extended Duration)
30-minute sustained fire exposure on treated assemblies.
Pass — No Flame Spread
ASTM E2768
(Extended Duration)
30-minute sustained fire exposure on treated assemblies.
Pass — No Flame Spread
DrJ Engineering TER 2504-101
Independent confirmation of IBC / IRC fire-protection compliance.
Code Compliant
DrJ Engineering TER 2504-101
Independent confirmation of IBC / IRC fire-protection compliance.
Code Compliant
UL GREENGUARD Gold
Low chemical emissions in occupied environments.
Certified
UL GREENGUARD Gold
Low chemical emissions in occupied environments.
Certified
Trout & Minnow Toxicity
(96-hour LC₅₀)
Aquatic toxicity safety threshold for waterway runoff.
LC₅₀ > 750 mg/L
Trout & Minnow Toxicity
(96-hour LC₅₀)
Aquatic toxicity safety threshold for waterway runoff.
LC₅₀ > 750 mg/L
How It Works
CitroTech-34 is applied directly to wood, where it dries clear and integrates with the surface fibers. Once cured, it enhances ignition resistance and reduces flame spread — helping treated assemblies achieve Class A fire performance without altering the wood's natural appearance or properties.
Applied to lumber or wood assemblies using spray or factory treatment methods.
Dries transparent with no change to the wood's natural appearance.
Enhances ignition resistance and limits flame spread at the wood surface.
Trust & Compliance
Our products undergo rigorous third-party testing to ensure the highest standards of safety and performance.
Low chemical emissions for safe use around people and animals.
Non-toxic certification (LC₅₀ > 750 mg/L).
Independent validation of ignition resistance.
Get connected with our team to learn how CitroTech can help safeguard your home, business, or community.