A covered hazmat truck has a flat tire. Where may it be driven under the repair-location exception?
Correct answer: To the nearest safe place for the necessary repair.
The tire must be repaired, replaced or properly inflated before driving, except travel to the nearest safe place to perform that work. Other safe-operation requirements still apply.
Source: 49 CFR 397.17(b). Official eCFR XML dated September 11, 2026; reviewed September 15, 2026. ↗
A tire on a covered hazmat vehicle is found overheated. What must be resolved before further operation?
Correct answer: The cause of the overheating must be corrected.
The driver must cause the overheated tire to be removed to a safe distance and correct the cause before operating again. Arrange qualified help and maintain applicable parking and attendance precautions.
Source: 49 CFR 397.17(c)–(d). Official eCFR XML dated September 11, 2026; reviewed September 15, 2026. ↗
A Class 3 placard-required truck approaches an ordinary railroad grade crossing with no applicable exception. Where must it stop?
Correct answer: Between 15 and 50 feet from the tracks.
For a covered vehicle, stop within 50 feet but not closer than 15, then look and listen. Use a gear that allows crossing without shifting.
Source: 49 CFR 392.10(a), (a)(3)(vi). Official eCFR XML dated September 11, 2026; reviewed September 15, 2026. ↗
A cargo tank formerly used to transport hazardous material is empty. At an ordinary grade crossing with no applicable exception, does empty status alone remove the federal stop requirement?
Correct answer: No; the rule includes loaded and empty hazardous-material cargo tanks.
392.10(a)(4) expressly covers such cargo tanks whether loaded or empty. The specific crossing exceptions in paragraph (b) must be considered separately.
Source: 49 CFR 392.10(a)(4), (b). Official eCFR XML dated September 11, 2026; reviewed September 15, 2026. ↗
After making a required railroad stop, how should the driver choose a gear for crossing?
Correct answer: Choose one that allows the whole crossing without shifting.
The rule requires a gear that permits completing the crossing without a gear change and prohibits shifting while crossing.
Source: 49 CFR 392.10(a). Official eCFR XML dated September 11, 2026; reviewed September 15, 2026. ↗
Which shipping information helps responders locate the appropriate entry in the Emergency Response Guidebook?
Correct answer: The proper shipping name and material identification number.
The handbook explains that ERG information is indexed by proper shipping name and identification number. Accurate hazard communication helps responders find the applicable guidance.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 9.7.1, Emergency Response Guidebook; physical PDF page 243 (printed 243); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
You notice an unfamiliar leak from hazardous cargo. How should you identify the material without deliberately exposing yourself?
Correct answer: Use available shipping information from a safe position.
Do not identify a hazardous leak by touching, tasting or deliberately smelling it. Use papers and safe observations, keep away and seek qualified emergency assistance.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 9.7.3, identifying a leak without deliberate exposure; physical PDF page 244 (printed 244); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
Hazardous cargo is leaking and the driver wants to continue to a truck stop to find help. What is the appropriate response?
Correct answer: Stop safely and call or send for help instead of spreading the leak.
The handbook warns against continuing a leaking shipment to find a phone or truck stop. Movement is limited to what safety requires and what can be done without endangering people or spreading contamination.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 9.7.3, stopping safely and obtaining help for a leak; physical PDF page 244 (printed 244); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
Hazardous cargo is burning and the driver lacks specialized firefighting training and equipment. What should the driver do?
Correct answer: Withdraw, warn others and summon emergency responders.
A hazardous cargo fire calls for trained, equipped responders. Keep shipping information available when safely possible and do not put yourself into the hazard.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 9.7.3, fires involving hazardous cargo; physical PDF page 244 (printed 244); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
While waiting for responders at a hazardous-material release, which location does the handbook recommend for people kept away from the scene?
Correct answer: Far away and upwind of the release.
Keep people far away and upwind and warn them about the danger. Actual isolation distances and protective actions depend on the material and responders' guidance.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 9.7.2, keeping people far away and upwind, continued from page 243; physical PDF page 244 (printed 244); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
What information is especially useful when someone contacts responders about your hazardous-cargo incident?
Correct answer: Exact location, incident details and known shipment identification.
Give the exact location and direction of travel, what happened, carrier details and known proper shipping name, class and identification number. Do not approach the hazard merely to gather missing information.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 9.7.3, information when obtaining help, continued on page 245; physical PDF page 244 (printed 244); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
A transportation incident meets 171.15's NRC telephone-report criteria. When must the person in physical possession notify the NRC?
Correct answer: As soon as practical, no later than 12 hours after occurrence.
The telephone deadline is as soon as practical and within 12 hours. This is not permission to delay emergency assistance; the detailed written report has a separate deadline.
Source: 49 CFR 171.15(a). Official eCFR XML dated September 11, 2026; reviewed September 15, 2026. ↗
A hazardous material directly causes the public to be evacuated for exactly one hour. Does this meet the evacuation trigger for NRC telephone reporting?
Correct answer: Yes; the trigger is one hour or more.
The current rule includes an evacuation lasting exactly one hour. The older handbook's more-than-one-hour wording should not be used to exclude this incident.
Source: 49 CFR 171.15(b)(1)(iii). Official eCFR XML dated September 11, 2026; reviewed September 15, 2026. ↗
A hazardous material directly causes an injury requiring admission to a hospital during transportation. Does that meet an NRC telephone-report trigger?
Correct answer: Yes; hospital admission is one of the listed triggers.
An injury requiring admittance to a hospital as a direct result of the hazardous material is a listed trigger. Mere cost estimates are not a substitute for checking the actual criteria.
Source: 49 CFR 171.15(b)(1)(ii). Official eCFR XML dated September 11, 2026; reviewed September 15, 2026. ↗
After an incident covered by 171.16, what is the ordinary deadline for the detailed hazardous-material incident report?
Correct answer: Within 30 days of discovering the incident.
The person in physical possession at the incident must submit the required DOT Form F 5800.1 within 30 days of discovery. This is separate from any prompt emergency call and NRC telephone notice.
Source: 49 CFR 171.16(a). Official eCFR XML dated September 11, 2026; reviewed September 15, 2026. ↗
At pickup, a Division 6.2 package is damaged and appears to be leaking. What should the driver do?
Correct answer: Do not accept it; contact the supervisor about the damage.
The handbook says damaged or leaking infectious-substance packages should not be accepted and the supervisor should be contacted. Avoid contact and leave specialist handling to trained personnel.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 9.7.4, Class 6 infectious substances; physical PDF page 246 (printed 246); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
