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Top 4 Common Regulatory Myths in Fleet
Several common misunderstandings of motor carrier safety regulations resurface year after year. Some seem plausible and even have a hint of truth. Nevertheless, these common myths are just that — myths.

Stay up-to-date on current fleet-related regulations. If you can’t locate a specific requirement in the regulations, don’t take it as truth.
Photo: Work Truck
Several common misunderstandings of motor carrier safety regulations resurface year after year. Some seem plausible and even have a hint of truth. Nevertheless, these common myths are just that — myths.
Department of Transportation (DOT) regulations for truck drivers are constantly changing and are often misunderstood.
Provided are the top four most common misconceptions, along with the possible source of each:
1. Air Conditioning Requirements in a Commercial Motor Vehicle (CMV)
Each summer, we receive requests to settle a debate between commercial truck drivers and their safety managers. Drivers contend that commercial motor vehicles (CMVs) must be equipped with air conditioning (AC) that is in working order. Managers claim it’s not a requirement.
So, who’s right?
The Federal Motor Carrier Safety Regulations (FMCSRs) do not require a commercial motor vehicle be equipped with AC. It is not listed as one of the required parts and accessories in 49 CFR Part 393. Therefore, it is not a violation of the FMCSRs if a vehicle is not equipped with AC, nor is it a violation if the AC is not functioning.
However, the Occupational Safety and Health Administration’s (OSHA) General Duty Clause (GDC) requires employers to protect employees from recognized, serious hazards, regardless of whether there is a specific standard addressing that hazard.
OSHA often uses the GDC to cite employers for not protecting workers from heat stress. If an incident of a heat-illness is investigated, the company could be cited by the agency.\
2. Spare Pair of Glasses
Truck drivers required to wear corrective lenses often mistakenly believe they need to show officers an emergency pair of glasses.
What is the origin of this myth? There used to be a requirement (§392.9a) for work truck drivers who wore contact lenses to have spare lenses. The section was removed from regulations in 1994. And, there was never a requirement to have two pairs of actual glasses, as some rumors today assert.
3. Reporting Crashes & Truck Accidents Directly to the DOT
A common question we receive is, “Where or how do we report crashes directly to the Federal Motor Carrier Safety Administration (FMCSA)?”
Current regulations do not require motor carriers contact FMCSA directly. Instead, motor carriers must maintain an accident register (§390.15) listing the details of crashes that meet the criteria of the accident definition in §390.5 (i.e., fatality, towing, or injury).
The accident register is kept for three years and would be presented to an investigator in the event of a motor carrier audit. This same document is referenced when a company receives an inquiry into the safety performance history of a current or former driver.
The requirement to report accidents to the FMCSA appeared in 49 CFR Part 394, which was removed and reserved when §390.15 replaced it in 1993.
4. Truck Driver Drug Tests with DOT Physicals
It has been decades since Part 382 replaced Subpart H to Part 391 (previous DOT testing rules).
Some carriers and their service providers continue to follow one specific obsolete requirement — a DOT drug screen with each medical recertification. The regulation (§391.105, Biennial or periodic testing) used to require a drug test at least once every two years, which is the maximum medical certification.
When FMCSA’s testing rules were overhauled, and §391.105 was removed and reserved, the requirement was not carried over to Part 382. Currently, a biennial or periodic test performed during a physical is not an allowable reason for testing under DOT authority.
Keep Misinformation to a Minimum
How do you keep from falling prey to myths such as these?
One of the easiest ways is to keep up to date on regulatory changes. Stay up-to-date through following reputable listservs, regularly checking FMCSA’s website, and subscribing to trade publications like Work Truck for the latest news and trends.
If you can’t locate a specific requirement in the regulations, don’t take it as truth. You can always pose your question to trusted subject-matter experts. Your regional FMCSA office is another starting point for clarification.
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