Some approved hazardous substances need permission before you can use them. Find out which substances these are and how to apply.

If you are unsure whether your product requires a permission from the EPA, you can search the HSNO Approvals Register or the HSNO Controls database and check the controls that apply.

Search the HSNO Application Register database

Search the Approved hazardous substances with controls database

Aquatic herbicides

You may need to obtain permission from us if you will be using aquatic herbicides in any of the following ways:

  • undertaking a plant pest control operation in an aquatic environment
  • applying certain herbicides on or into water 
  • applying certain herbicides near enough to water that it can reasonably be expected that the substance will enter water.

You need permission to use a herbicide with one of the following active components:

  • metsulfuron-methyl
  • haloxyfop-R-methyl
  • imazapyr isopropylamine
  • triclopyr trimethylamine
  • endothall (Aquathol K and Aquathol super K).

To apply for permission, fill in the form below and send it to us.

Application form for permission to use a hazardous substance (DOC, 439KB)

A guide to applying for a permission (PDF, 50KB)

Sodium nitrate

Permission is required for sodium nitrite control operations on feral pigs on any land not administered by the Department of Conservation (DOC).

To request a permission be granted, fill in the application form below and send it to us.

Application form for sodium nitrite permission (DOCX, 363KB)

Vertebrate Toxic Agents (VTAs)

If you are undertaking a pest control operation that requires the use of certain VTAs, you may need a permission from the Department of Conservation and/or the Public Health Unit (PHU) of the local District Health Board. 

If you are using a VTA that requires a permission from the PHU, you will need to make an application on the approved application form, available from the Ministry of Health.  

You will need a permission from DOC to use any VTA on land administered or managed by DOC. To obtain this Permission, contact your local Department of Conservation office.  

You can find out more about when a permission is required in the guidance document.

Guidance on when a permission from DOC and/or PHU is required (PDF, 91KB)