Tanker Loading and Unloading Procedures
Domain 2 tests loading and unloading: site set-up, static electricity control, filling to the correct outage, and staying with the transfer. Questions often turn on sequence - what you connect or open first and last.
Before the transfer
- Engine off unless the pump/PTO requires it; parking brake set; wheels chocked.
- Confirm product, quantity and compartment assignment against the paperwork.
- Ground and bond before opening any dome cover or valve; keep the connection until the transfer is finished and the tank is closed.
- No smoking, no open flame, no running engine near flammable vapors.
During the transfer
- Watch the fill; never rely on the automatic shutoff alone.
- Do not overfill; leave the required outage for expansion.
- For flammable liquids, attend the transfer - generally within 25 feet with the vehicle in clear view - and never leave to do paperwork.
- Stop if you see a leak, a bulging hose or a vapor release.
Worked example
A 6,000-gallon tank requires 2% outage. Two percent of 6,000 is 120 gallons, so the maximum load is 5,880 gallons. The order is 5,900 gallons. Answer: you cannot put it all in one tank; reduce the load, split it, or use a larger tank. If you filled to 5,900, a modest temperature rise would push liquid out of the vent.
Traps that cost marks
- Bonding after the hatch is already open.
- Treating "full" as filled to the top.
- Trusting the previous driver's paperwork instead of the current order.