The California Air Resources Board is following through on its promise to clamp down on emissions from reefer diesels

. They're putting out the "unwelcome" sign to units that don't burn cleanly enough. Because so many operators of what CARB calls transport refrigeration units, or TRUs, send rigs into California to deliver goods and pick up produce and other perishables, the new, strict rules will affect most reefers in the U.S., and many in Canada and Mexico.

CARB acted after getting a waiver from the U.S. Environmental Protection Agency that allows California authorities to set reefer standards stricter than those written by the feds, just as CARB has done for years on automotive emissions. Requesting the waiver was CARB's response to a complaint by industry groups that delayed implementation of the new reefer rules by six and a half months. The effective date is now July 17.

(Editor's note: After we went to press with this issue, CARB delayed the implementation date. Low-Emission TRU In-Use Performance Standards for 2001 and older TRU engines -- originally scheduled for this month -- have been delayed until December 31.)

Instead of following EPA's Tier limits for reefer-diesel exhaust, CARB has set phase-out dates for older, existing equipment. Particulates are the main target, but NOx should also be reduced.

Basically, TRUs bought today are good for seven years of operation in California. Those older than seven years must be upgraded. That means that this month, units built for the 2001 model-year or older are banned unless they've been upgraded to meet limits for current engines. On Dec. 31, '02- and earlier-model units are banned unless they're modified, and so on, up to 2013, when the most stringent EPA Tier limits are due.

Compliant TRUs must display decals showing a registration number issued by CARB. Instructions can be found on the Web at www.arb.ca.gov/diesel/tru.htm.) Carrier Transicold and Thermo King also will assist owners with TRU registrations.

There are several ways to meet the new rules:

* Avoid sending non-compliant TRUs into California, or if you're headquartered there, send or sell older equipment outside the state.

* Lease or rent legal TRUs and trailers. Many leasing companies are stocking up on new trailers with CARB-compliant reefers.

* Modify existing TRUs or replace them.

* Use "alternative technologies."

Natural gas fuel, electric standby mode or chemically cooled units would qualify. Natural gas engines are not yet available for reefers, electric-equipped TRUs need a high-voltage socket to plug into and while on the road must still use their diesels, and chemical TRUs are still rare and costly.

Options for modification of non-complying TRUs include:

* Remove the old diesel and install a new compliant engine;

* Install an approved diesel particulate filter on the existing engine's exhaust;

* Install a complete new reefer unit on the existing trailer or truck body; or

* Buy a new reefer unit on a new trailer or truck body.

The older the unit, the less sense it makes to modify it, because the compressor, evaporator and other components aren't as efficient as newer designs. Money spent on a new engine might save some fuel, but a DPF won't pay for itself except that the useful life of the rest of the TRU and vehicle can be extended.

Times being what they are, builders of reefers, trailers and truck bodies would prefer to sell you new equipment. They also have products that are far more efficient, and can equip them with electric standby systems that keep the reefers legal while they're parked at docks. And they might even cut you a deal that's hard to ignore.

From the July 2009 issue of Heavy Duty Trucking.