Michigan CDL Tanker cheat sheet

Pre-trip items unique to tankers: dome covers and gaskets, vents and vent valves, internal and external valves, discharge outlets and caps, grounding/bonding studs, and spill containment equipment.

A cargo tank must be marked with its specification plate (MC 306/DOT 406 for flammable liquids, MC 307/DOT 407 for low-pressure chemicals, MC 312/DOT 412 for corrosives, MC 331 for high-pressure gases); the plate shows design pressure, capacity, and test dates.

Cargo tank test and inspection intervals: external visual inspection and leak test at least once a year; internal visual inspection and thickness test at least every 5 years for most tanks (more often for corrosives).

Before loading, verify the tank is the correct specification for the product, that all valves and dome covers are closed except the one being loaded, and that the tank has been purged or is compatible with the new product.

Bottom loading requires the vapor-recovery connection to be made, the loading arm or hose grounded to the tank, and the overfill sensor (optic or float) connected and working.

Top loading: bond the tank to the loading rack before opening the dome, keep the loading line grounded, and stand upwind; splash loading of flammables is prohibited, so use an extension pipe reaching near the bottom.

Grounding and bonding: bond the cargo tank to the loading facility and ground the facility; a bond equalizes potential between truck and rack, a ground connects both to earth.

Never leave a loading or unloading operation unattended; stay within sight and reach of the controls and the emergency shutdown.

After loading, check dome covers, seals, and valves, remove and stow hoses, and confirm the tank is not overfilled before moving.

Liquid surge is forward and back movement of product in a partly filled tank; it is strongest when the tank is about half full and least when nearly full or nearly empty.

Surging liquid shifts the center of gravity and produces a force that can push a truck through a stop line or into a skid; surge also affects steering and braking distance.

Baffles are internal walls with holes that divide the tank into compartments; they slow the flow of liquid and reduce surge but do not eliminate it.

A smooth-bore (unbaffled) tank carries the greatest surge; baffled tanks and multi-compartment tanks reduce it, and completely filled or empty tanks have essentially no surge.

High center of gravity: a loaded tanker's weight sits well above the frame, so the vehicle rolls over at a lower lateral acceleration than a loaded van; rollover threshold drops as the tank empties.

Side-to-side slosh in a partly filled tank can combine with a curve to lift the inside wheels; avoid abrupt steering and do not enter a curve too fast.

Baffle compartments are not separate cargo tanks for specification purposes but do create trapped product; know compartment capacities so you do not overload an axle.

Front-to-back surge increases stopping distance; allow extra following distance and brake earlier and more gently than with a dry van.

Speed in curves: slow to a safe speed before entering the curve, then maintain or gently increase power; braking while turning on a tanker invites a rollover or jackknife.

Rollover is the leading serious crash type for tankers; posted curve speeds are for cars, so use a lower speed for a high-center-of-gravity tank vehicle.

Braking: use controlled, progressive braking, avoid hard stops that trigger surge, and remember that a partly loaded tank needs a longer stopping distance.

Skids: if the drive wheels skid under acceleration, ease off the accelerator and steer in the direction you want to go; if the front wheels skid, release the brake to regain steering.

Wet or icy roads multiply tanker risk because the high center of gravity and surge combine with reduced traction; reduce speed well below the posted limit.

Railroad crossings and bumps: slow down, because a stiff suspension and high load can bounce the tank and shift liquid, and low clearance can snag the tank or piping.

Downgrades: select a gear before the grade, use engine braking, and avoid riding the brakes; a loaded tanker can fade brakes and surge forward on a steep descent.

Off-tracking and tail swing: a long tanker cuts corners, so swing wide on turns and watch the rear of the tank in tight spaces.

Tunnel and bridge restrictions apply to hazardous cargo tankers; check the route for hazmat routing designations before departure.

A tanker carrying a placarded quantity of hazmat needs the placards on all four sides (both sides and both ends) for the material, plus the UN number displayed as required.

Shipping papers must accompany the load, be within the driver's reach in the cab, and state the proper shipping name, hazard class, UN number, packing group, and total quantity.

Emergency response information must be carried with the shipping papers; the ERG (Emergency Response Guidebook) is the standard reference for initial isolation and protective action distances.

Cargo tank motor vehicles require a CDL with the tank vehicle (N) endorsement; hazmat (H) endorsement is separate and requires a TSA threat assessment and knowledge test.

Flammable liquid tanks must be bonded and grounded during loading and unloading; static electricity is a real ignition source, and splash filling is prohibited.

Corrosive and poison-inhalation-hazard materials require special handling: know the material's PIH status, keep upwind, and follow the ERG isolation distance if a release occurs.

Unloading: set the parking brake, chock wheels, shut off the engine (unless the pump requires it), attend the controls, and verify the receiving tank has room before opening valves.

A cargo tank with a leak, defective valve, or missing placard is out of service; do not move it until repaired, and report the defect to the carrier.

Parking a placarded tanker: do not park within 5 feet of a roadway, and follow local rules for tunnels, bridges, and populated areas; never park near an open flame.