The House surface transportation subcommittee yesterday approved a measure that would relax federal regulation of the nation's trucking industry although it would not go quite as far toward deregulation as a Senate-passed bill.

Nevertheless, the measure is a compromise that was worked out with key Senate members and the Carter administration and retains most of the important elements of reform legislation advocated by deregulation proponents. The bill would:

Significantly lower barriers to entry into the trucking business by new firms.

Establish a zone of pricing flexibility within which trucking companies can alter their freight rates without interference by the Interstate Commerce Commission.

Establish a schedule for the removal of restrictions on trucking operations that now prohibit companies from carrying certain commodities or stopping at certain cities or traveling the more direct routes.

Cut back on the antitrust immunity granted the industry that now allows companies collectively to decide on the rates shippers will be charged for trucking services.

The measure cuts back significantly on a Senate-passed provision that would have exempted from all federal trucking regulation the movement of all food products. Now, raw agricultural products are exempt from federal regulation and move at lower rates. The narrower House provision would allow owner-operators to carry processed food without significant federal involvement.

The compromise was accepted by the House subcommittee without any substantive amendments during the day-long session. Repeated attempts to amend the bill were defeated after the key members -- subcommittee Chairman James Howard (D-N.J.), ranking minority member William Harsha (R-Ohio) and Bud Schuster (R-Pa.) -- opposed them on grounds that the "delicate balance) of the compromise would be upset even though they might agree in principle. "This could just blow the compromise right out of the water," Shuster said in opposition to one proposed amendment.

"Are you going to legislate a bad bill because we don't want to go to conference?" Rep. Allen Ertel (D-Pa.) asked at one point when the subcommittee leaders opposed an amendment he sponsored that would have reduced regulation further.

According to a Senate Commerce Committee source, if the House bill stays as it is or gets stronger so that it resembles the Senate bill even more, Sens. Howard Cannon (D-Nev.) and Bob Packwood (R-Ore.), the bill's chief sponsors, would be inclined to recommend to the Senate that the bill be accepted without a conference.

Two key administration officials praised the House subcommittee's action, indicating the President would be ready to sign the bill if it survives a mark-up, scheduled for Thursday, and House action relatively intact.

Stuart Eizenstat, assistant to the President for domestic affairs and policy, congratulated the subcommittee for scoring "a major victory in the fight against inflation." And Transportation Secretary Neil Goldschmidt said the bill "does what needs to be done. It brings more competition to the trucking industry. It eliminates the worst form of truck price-fixing, and it offers opportunities to improve the quality of freight service to rural areas and small towns."