Wood preservation facilities, ammoniacal copper zinc arsenate: chapter C-12

12. Environmental Emergency Notification and Contingency Planning

Preparedness for emergencies is essential in any wood preservation facility. Hence, facilities using ACZA should prepare detailed contingency plans and have them readily available to ensure that response to spills and fires is quick, safe and effective.

12.1 Environmental Emergency Notification

The Environmental Emergency Regulations and its requirements are applicable for ACZA since it contains arsenic, listed in Schedule 1 of CEPA 1999.

Please refer to Section 12.1 of Part I, Chapter A - General Recommendations for All Wood Preservatives.

12.2 Spill Contingency Planning

Please refer to Section 12.2 of Part I, Chapter A - General Recommendations for All Wood Preservatives.

The following additional recommendations apply to ACZA facilities if a spill of ammonium hydroxide, ACZA solution or arsenic acid occurs:

• Immediately put on appropriate NIOSH-approved respirators, full-face mask / breathing apparatus, (NIOSH-approved respirators and full-face mask should be equipped with high-efficiency filter cartridges in combination for acid gas and ammonia with a P100 prefilter, e.g., TC23-C, TC14-G).
• Always stay upwind to avoid potential exposure to ammonia fumes.
• For ammonia spills, use water spray to knock down vapours.
• If tanks other than normal work tanks are used for salvage purposes, ensure compatibility of materials, i.e., do not use galvanized or aluminium tanks because of the corrosiveness of ammonia.

12.3 Fire Contingency Planning

Although the ingredients of ACZA and ACZA solutions are not flammable, precautions should be taken in the event that a fire occurs in the vicinity of ACZA solutions, arsenic acid or ammonia. Ammonia gas could be released if ACZA or aqua ammonia are heated. Mixtures of ammonia and air in an enclosed space with an ignition source could be explosive. In addition, heating of ACZA could result in the formation of toxic arsenic vapours. Using water blanket areas, water spray to suppress toxic dust and gases and keeping temperatures of oxidizable materials below that for ignition, are additional recommendation that can be considered.

It is, therefore, important that ACZA wood preservation facilities devise an adequate contingency plan for fire protection, including storing a copy of all necessary documents in a fire proof box outside the entrance to the facility.

Please refer to the National Fire Code of Canada (always refer to last version available) and to Section 12.3 of Part I, Chapter A - General Recommendations for All Wood Preservatives.