Technical
Technical » Hazard Class Selection Guide
H1
Sawn lumber used in situations continuously protected from the weather. The purpose of preservative treatment is to protect against attack by wood-boring insects.
H2
Sawn lumber and plywood used in interior situations where there is a slight risk of decay and a risk of termite attack.
H3
Sawn lumber and plywood used in exposed exterior situations, but with no contact with the ground.
H4
Sawn lumber, round wood and plywood used in exterior situations where there is ground contact but in non-critical situations.
H5
Sawn lumber, round wood and plywood used in exterior situations that come into contact with the ground and have extreme decay hazards or the end use requires greater protection.
H6
Sawn lumber and roundwood used in a marine environment.
HAZARD CLASS SELECTION TABLE
Hazard Class |
Exposure |
Specific Service Conditions |
Biological Hazard |
Typical Uses |
|
H1 |
Inside, above ground |
Completed protected from the weather and well ventilated, and protected from termites |
Lyctids |
Susceptible framing, flooring, furniture, interior joinery |
|
H2 |
Inside, above ground |
Protected from wetting. Nil leaching |
Borers and termites |
Framing, flooring, and similar, used in dry situations |
|
H3 |
Outside, above ground |
Subject to periodic moderate wetting and leaching |
Moderate decay, borers and termites |
Weatherboard, fascia, pergolas,(above ground), window joinery, framing & decking |
|
H4 |
Outside, in ground |
Subject to severe wetting and leaching |
Severe decay, borers and termites |
Fence posts, greenhouses, pergolas (in ground) and landscaping timbers |
|
H5 |
Outside, in-ground contact with or in fresh water |
Subject to extreme wetting and leaching and/or where the critical use requires a higher degree of protection |
Very severe decay, borers and termites |
Retaining walls, piling, house stumps, building poles, cooling tower fill |
|
H6 |
Marine waters |
Subject to prolonged immersion in sea water |
Marine wood borers and decay |
Boat hulls, marine piles, jetty cross-bracing, landing steps, and similar |
