OSD Storage Volume (SSR) Quick Estimator
OSD Tank Load Class Selector

Click your surface use over the tank to see the load class range it typically requires. Final confirmation is your engineer’s call, based on site-specific traffic and cover-depth calculations.

Surface Over Tank Typical Load Class Example
Landscaped / lawn (no vehicle access) HS-20 Residential garden bed
Residential driveway HS-25 Single/multi-dwelling driveway
Carpark / commercial access road D400 Retail or office carpark
Industrial hardstand / plant area SLW60 Warehouse hardstand
Select a surface over the tank
to view the recommended load class.
Suggested Load Class
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Confirm the exact rating for your site: Request a Project Quote
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