We’re pleased to share an important regulatory update that reflects the success of MAA’s continued advocacy on behalf of our members.

In July 2019, MAA submitted a formal request to the Federal Motor Carrier Safety Administration (FMCSA) seeking an exemption for older portable conveyors from the brake requirements outlined in 49 CFR § 393.42(b). Our request was based on practical industry experience and safety considerations: conveyors manufactured prior to 2010 were not equipped with brakes because the drum brake systems available at the time often became clogged with sand and aggregate materials, rendering them ineffective and potentially creating road hazards during transport.

Since then, manufacturers have transitioned to disc brake systems, which perform more reliably in aggregate environments. However, older conveyors cannot be retrofitted with these modern braking systems. Despite this, the aggregate industry has maintained a strong safety record while transporting these brakeless conveyors.
 

FMCSA is now proposing to adopt MAA’s requested exemption into the Federal Motor Carrier Safety Regulations (FMCSRs) as an official rule change. This proposal would create a new exception—§ 393.42(b)(7)—specifically allowing for portable conveyors manufactured before 2010 to be transported without brakes, provided that certain safety conditions are met.

FMCSA reviewed safety data from 2020 through Q1 of 2024 and found that:

To ensure continued safe transport, FMCSA proposes the following conditions under the new exemption:

1. Stopping Performance: The towing vehicle and conveyor must meet the braking performance requirement in § 393.52(d)—stopping within 40 feet from 20 mph.
2. Weight Ratio Limit: The towed conveyor’s axle weight must not exceed 40% of the towing vehicle’s axle weight to maintain vehicle stability.
3. Speed Restrictions: Transport speed must not exceed 45 mph on two-lane roads or 55 mph on freeways.

FMCSA further notes that, due to the length of these conveyors, motor carriers typically require overlength permits from state agencies. These permits often include speed limitations that align with the proposed rule.
 

Portable conveyors manufactured prior to 2010 and used by the aggregate industry are not required to be equipped with brakes on all wheels provided:
(i) The combination of portable conveyor and towing vehicle meet the performance requirement in 49 CFR 393.52;
(ii) The sum of the axle weights of the towed vehicle does not exceed 40 percent of the sum of the axle weights of the towing vehicle; and
(iii) The maximum speed is limited to 45 mph on two-lane roads and 55 mph on freeways.
 

Next Steps

The proposed rule has been published in the Federal Register and is now open for public comment. MAA is actively working with the National Stone, Sand & Gravel Association (NSSGA) and other state aggregate associations to generate support during the public comment period.

We encourage our members to stay engaged and support this effort. This proposed change represents a common-sense update that recognizes longstanding industry practices while maintaining safety on the road.

Click here to view the Proposed Rule as published in the May 30, 2025 Federal Register

MAA will continue to monitor developments closely and provide updates as the rulemaking process progresses.