drums on wooden pallet

Achieving ISPM 15 Compliance: A Technical Guide to Methyl Bromide Fumigation

The International Standards for Phytosanitary Measures No. 15 (ISPM 15) requires heat or methyl bromide gas treatment of wood packaging materials before export shipping to prevent pest spread. When properly performed, methyl bromide fumigation effectively eliminates quarantine wood pests and pathogens.

In this comprehensive, technical guide, we examine key considerations, protocols, and procedures for effective methyl bromide fumigation in compliance with ISPM 15 parameters.

I.Methyl Bromide Treatment Overview


Methyl bromide is a broad spectrum fumigant that penetrates wood surfaces, residual bark, and cracks to kill organisms in all life stages. At normal temperatures, it has high volatility and diffusivity, making methyl bromide ideal for treating stacked wood products.

For ISPM 15, the minimum fumigation concentrations and duration vary based on temperature:

– At 10°C and above, the minimum concentration must reach 48 g/m3 over 24 hours

– Between 5°C and 10°C, the minimum concentration increases to 56 g/m3

– Below 5°C, uniform dispersion cannot be achieved 

If the measured concentration after 24 hours is below 95% of the minimum threshold, a 2-hour extension is permitted. Otherwise, full retreatment is required.

II. Technical Considerations Before Fumigation:

Here are the technical consideration we follow before a methyl bromide fumigation. 

  1. Wood moisture content should not exceed 75%, as high moisture inhibits penetration.
  2. Wood thickness is limited to 20cm, as diffusion through thicker wood is inadequate.
  3. Residual bark must be less than 3cm wide, as bark absorbs and adsorbs the fumigant.
  4. Use gas-proof sheets or tape for enclosure sealing to minimize leakage.
  5. Eliminate absorbent materials like cardboard from the treatment area.
  6. Maintain a minimum temperature of 10°C for even dispersion of methyl bromide.
  7. Adjust dosing to account for any excessive fumigant sorption by wood or surroundings.
  8. Allow 12+ hours after required exposure before aeration to permit desorption.
temperature control ispm 15 fumigation

III.Protocols for Methyl Bromide Fumigation

A. Preparation

The meticulous execution of protocols for methyl bromide fumigation is integral to ensuring the efficacy of the treatment and compliance with the International Standards for Phytosanitary Measures No. 15 (ISPM 15). The initial phase of preparation requires a strategic approach, with wood packaging articles stacked at intervals of 10-15cm to facilitate optimal gas circulation. Additionally, a thorough sealing of all cracks, joints, and entries using caulk, tape, or sand snakes is essential to prevent any escape of the fumigant. The positioning of fans and agitators plays a crucial role in the efficient distribution of methyl bromide, ensuring a uniform treatment across the stacked materials.

B. Dosing and Exposure:

The 2nd phase of methyl bromide fumigation, dosing and exposure, demands precision and monitoring throughout the fumigation process. The use of a vaporizer or wand allows for the accurate application of methyl bromide, taking into account both volume and minimum concentration requirements. Concurrently, gas analyzers and tubes are strategically placed to measure concentrations at various heights during the fumigation, with readings taken at intervals of 2, 4, and 24 hours. Flexibility is built into the protocol, as an extension of 1-2 hours is permissible if the 24-hour reading falls below the recommended threshold, provided the concentration remains at 95% or more of the minimum requirement.

C. Ventilation:

Ventilation, the third phase, is a critical component in the post-fumigation process. After the prescribed exposure time, a mandatory desorption period of 12 hours is observed before venting commences. During this phase, fans and openings are strategically utilized to actively flush residual fumigant from the wood, reducing concentrations to safe levels below 5 ppm. The safety of personnel is paramount during venting, and protective equipment is mandated to minimize any potential health risks. Placards and markings, indicative of the fumigation process, are only removed once the ventilation process is completed, ensuring that the treated wood packaging articles are ready for the next stage of certification.

D. Certification:

Certification, the final step in the methyl bromide fumigation protocol, involves the application of the ISPM 15 compliance stamp to all treated wood packaging articles. This certification not only signifies adherence to international phytosanitary standards but also assures stakeholders that the fumigation process has been diligently executed. The comprehensive nature of these protocols, from preparation to certification, underscores the commitment of professionals at Focus Pest Management to provide a reliable and compliant solution for methyl bromide fumigation services, ensuring the integrity of wood packaging materials destined for international trade.

methyl bromide fumigation in process

IV. Testing Fumigation Execution:

These are the 3 main process verification

  1. Cold Spot Mapping – Identify and test the area that is slowest to reach required temperatures, normally by placing sensors at various spots.
  2. Routine Sensor Calibration – Calibrate temperature and gas analyzers annually and verify all parts function properly.
  3. Control Chamber Trials – Perform test fumigations under controlled conditions with extensive sensor placement to validate treatment efficacy.

At Focus Pest Management we maintain full records of key process parameters and wood details for each methyl bromide fumigation batch. Our operators are trained to carefully control key variables and troubleshoot issues to ensure treatments meet ISPM 15 compliance thresholds every time. Ask us a quote by clicking on the button bellow.