There are a total of 6 levels of treatment. H1 through to H6. Each level of treatment is designed to suit a particular application. The most common of these is H3 and H4.
H1 – Inside use – Protection from some insects, not termites.
H2 – Inside use – Protection from insect attack including termites.
H3 – Exterior above-ground use – Protection from moderate decay (periodic wetting) and termites.
H4 – Exterior in-ground use – Protection from severe decay and termites for landscaping applications.
H5 – Exterior in-ground use – Protection from very severe decay and termites for structural applications.
H6 – Marine use – Protection from prolonged immersion in seawater and most marine borers.
H1 to H5 cannot be used in permanently wet environments, including areas that are boggy or areas that are susceptible to long periods of high moisture retention.
You must choose the correct Treatment Level for your application.