PTS Safe Systems of Work 3 — Questions and Answers
Question 1: Which of the following best describes a 'Blocking' arrangement in railroad safety?
- Physically placing a locomotive on the track to stop trains
- Using signals and rules to prevent train movements into a work area (Correct answer)
- Fencing off both ends of a work zone with barriers
- Notifying all local station masters of work activity
Correct answer: Using signals and rules to prevent train movements into a work area
Blocking uses operational rules and signal systems to prevent train movements from entering the limits of a designated work area.
Question 2: A PIC must hand back a SSoW authority before the stated expiry time if work is completed early. Why is this important?
- To avoid additional charges from the track owner
- So train operations can resume or other work can begin safely within those limits (Correct answer)
- To allow the next shift's PIC to take over the paperwork
- To satisfy union regulations on overtime work
Correct answer: So train operations can resume or other work can begin safely within those limits
Handing back authority promptly allows the controlling authority to restore normal train operations or reassign the limits, preventing unnecessary delays.
Question 3: Under what circumstance is it acceptable to extend the time limits of an active SSoW without contacting the controlling authority?
- When all workers agree it is safe to continue
- When the PIC judges no trains are scheduled
- It is never acceptable — extensions must always be authorized (Correct answer)
- When work is more than 75% complete
Correct answer: It is never acceptable — extensions must always be authorized
Time limits on a SSoW cannot be self-extended; any extension must be formally requested from and granted by the controlling authority.
Question 4: What action must a PIC take if radio or communication equipment fails during an active SSoW?
- Continue work but increase the number of lookouts
- Immediately stop work and establish an alternative communication method or withdraw from the SSoW (Correct answer)
- Send one worker to a signal box to maintain contact
- Reduce the working gang to two people only
Correct answer: Immediately stop work and establish an alternative communication method or withdraw from the SSoW
Loss of communication is a critical safety failure; the PIC must stop work immediately and either restore communication or formally withdraw from the SSoW.
Question 5: What does the term 'absolute block' mean in the context of protecting a work site?
- All trains must slow to walking pace through the work zone
- No train movement is permitted into the protected section under any circumstances (Correct answer)
- Trains may proceed only after receiving a hand signal from the PIC
- The section is blocked to freight trains but open to passenger traffic
Correct answer: No train movement is permitted into the protected section under any circumstances
An absolute block means no train movement whatsoever is permitted into the protected limits, providing the highest level of track protection.
Question 6: A second gang needs to work within the same SSoW limits already held by another PIC. What must happen?
- The second gang's supervisor must obtain a separate, independent authority
- The original PIC must formally include the second gang within their authority after notifying the controlling authority (Correct answer)
- Both PICs hold joint authority automatically
- The second gang may proceed as long as they stay 500 feet from the first gang
Correct answer: The original PIC must formally include the second gang within their authority after notifying the controlling authority
Multiple gangs within the same limits must be covered under a single, clearly defined authority with the original PIC taking responsibility or with formal sub-authority arrangements.
Question 7: Which of the following is classified as a 'last resort' protection method and should only be used when no other method is practicable?
- Possession of the line
- Lookout protection (Correct answer)
- Absolute block working
- Track circuit clips
Correct answer: Lookout protection
Lookout protection is considered a last resort because it relies on human reaction and provides less certainty than track possessions or electrical protections.
PTS Safe Systems of Work 3
Which of the following best describes a 'Blocking' arrangement in railroad safety?