Heat Treatment Standards

Heat Treatment & Quarantine Requirements

A heat-treatment standard includes both the time and temperature required to disinfest firewood of insect life stages and viable pathogens. All three standards (T314-a, b and c) can impact survivorship of insects and pathogens when appropriately applied and documented. See Heat Treatment for more information.

Heat Treatment Standard Comparison in Existing Firewood Regulations (Jan 1, 2020)

StateHeat Treatment Standard ReferencedRequirements for Permits or Notification
Florida T314-c: 71.1 °C for 75 minutes (not explicitly stated in quarantine) Certification and Master Permit
New HampshireT314-a: 60 °C for 60 minutesCertification
New YorkT314-c: 71.1 °C for 75 minutesCertification
OregonT314-a: 60 °C for 60 minutesNot explicitly stated
PennsylvaniaT314 (any federal treatment therein)Certification
UtahT314-c: 71.1 °C for 75 minutesCertification and Advance Notification
VermontT314-c: 71.1 °C for 75 minutesCertification

The science and data associated with heat disinfestation, heat-treatment standards, and kiln certification is summarized in the Heat Treatment appendix. Please review for additional background information.

General Benefit

Heat-treatments kill insects and pathogens found in or on firewood creating a more phytosanitary product. Regional and national consistency in heat-treatment standards benefits states’ abilities to maintain forest products markets.

T314- B: 56 °C for 30 minutes


  • Lowest standard and aligned with USDA gypsy moth and ISPM 15 standards.
  • Controls life stages of many insects and pathogens.
  • Adequate for control of life stages of Asian longhorned beetle1.
  • Encourages broad participation by the industry.


  • Inadequate for control of pests such as emerald ash borer and some thermophilic pathogens.

T314-A: 60 °C for 60 minutes


  • T314-a is the current USDA emerald ash borer firewood standard, and is therefore used by many states.
  • Provides security that life stages of more insects and pathogens are controlled when compared to T314-b.
  • Standard is achievable by a broad range of firewood kilns.


  • May provide incomplete control of some thermophilic pathogens.
  • Firewood originating in a gypsy moth quarantine area is certified to T314-b and therefore states requiring T314-a will need additional certification.

T314-C: 71.1 °C for 75 minutes


  • Highest treatment standard in the USDA’s Logs and Firewood T314 series.
  • Greater confidence about control of thermophilic pathogens and insects.
  • Greater confidence of adequate treatment when wood core temperatures are not measured or recorded.


  • Inability to certify firewood kilns unable or unwilling to run at these higher temperatures.
  • Potentially regulating the industry to higher standards than necessary.
  • Firewood from sources with lower treatment requirements would need additional certification to comply with this standard.

Heat Treatment Standard Recommendations

  1. Explicitly state heat treatment standards by temperature and duration.
  2. Explicitly state standards are as measured in the core of the firewood.
  3. Require that heat-treated firewood is certified by a federal, state, or 3rd party organization.
  4. Require that treatment, supply, and sales records are maintained and auditable by a certifying agency.
  5. Consider use of the T314-a: 60 °C for 60 minutes standard as the required standard.
  6. Consult with stakeholders if considering the higher T314-c: 71.1 °C for 75 minutes standard.

Sample Definitions

  1. “Treated firewood” means any firewood certified as heated to 60 °C (140 °F) for 60 minutes at wood core, OR
  2. “Treated firewood” means any firewood certified as heated to 71.1 °C (160 °F) for 75 minutes at wood core, OR
  3. “Treated firewood” means any firewood certified as heated to 56 °C (133 °F) for 30 minutes at wood core.

1 Myers, S.W. and S.M. Bailey. 2011. Evaluation of the ISPM-15 Heat Treatment Schedule for Asian Longhorned Beetle, Anoplophora glabripennis (Coleoptera: Cerambycidae) For. Prod. J. 61: 46-49.


Quarantine Template

Firewood Definitions

Firewood Labeling

Heat Treatment Standards

Compliance Agreements

Certification Programs