Speed Restrictions – Railway GK Capsule

1. What is a “Speed Restriction”?

A speed restriction is any mandatory reduction below the sanctioned sectional speed, ordered through a “Speed Certificate” or “Special Instruction”. It may be temporary (TSR – Temporary Speed Restriction) or permanent (PSR – Permanent Speed Restriction).

2. Technical Definitions & Key Terms

3. Speed Restriction – Categories & Values

A. Geometry-based PSRs (typical)

B. Points & Crossings

• Ordinary switch (1 in 12): 15 km/h on facing & 30 km/h on trailing.
• CMS (Cast Manganese Steel) 1 in 16/20 with thick-web tongue rail: 50 km/h (facing) & 75 km/h (trailing) after 2018 retrofit.

C. Bridges

• Ghat section arch bridges (span < 30 m): 75 km/h (BG), 50 km/h (MG heritage).
• RC / PSC girder with longitudinal articulation: 110 km/h (BG) subject to oscillation test ≤ 0.15 g vertical acceleration.

D. Track Quality Index (TQI) based TSR

Introduced 2022: if TQI > 65 (1.5 m chord versine > 12 mm) → 20 km/h reduction till resurfacing.

4. Historical Timeline

• 1854: First speed “limit” – 30 mph (≈48 km/h) for “express” on GIPR.
• 1926: “Speed Certificate” system formalised after derailment of Howrah–Bombay Mail at Agra.
• 1957: Maximum for steam hauled passenger fixed at 90 km/h; freight 65 km/h.
• 1969: Rajdhani introduced with 120 km/h; first 1 in 20 switches allowed 60 km/h.
• 1988: CRS authorised 130 km/h on Delhi–Agra section (first < 160 km/h).
• 2014: Mission Raftaar – aim to raise sectional speed to 160 km/h on Golden Quadrilateral.
• 2018: Automatic ‘Signalling based Speed Restriction’ (SBSS) rolled out on Ghaziabad–Aligarh.
• 2020: First 160 km/h Goods train (Roll-on Roll-off) run on New Delhi–Mumbai WR route under T-14 policy.
• 2023-24: Kavach (ETCS-L1) mandatory for > 130 km/h; restriction removed when train under ATP supervision.

5. Current Status & Recent Updates (2023-24)

1. Mission 160: 8,000 km identified; PSR removed/relaxed on 1,400 km after infrastructure up-gradation.
2. Vande Bharat (VB): Operates at 130 km/h on existing track; no additional PSR if track category ≥ “Good-very good” (TGI 41-50).
3. KAVACH corridor: Wherever KAVACH commissioned, TSR of 10 km/h imposed during commissioning phase; lifted after 30 days of stable operation.
4. Digital Speed Restriction Module (DSRM): Pilot on Central Railway (2023); TSR now fed directly into Crew Lobby & Loco SI units.
5. Penalty: Non-compliance of PSR/TSR – SPAD (Signal Passed At Danger) category “A” – suspension of LP/ALP for 7 days minimum.
6. Environment-based: Pollution-control TSR of 80 km/h imposed in Delhi-NCR during GRAP-IV (Nov. 2023).

6. Procedure for Imposing / Withdrawing a TSR

1. Detection – PWI / AEN during patrolling or USFD testing.
2. Speed Certificate – filled in triplicate (white, pink, green).
3. Approval – DEN within 24 h; countersignature Sr. DOM.
4. Issue CO – Section Controller; copy to Crew Lobby, Station Manager, TPC.
5. Posting – One notice at each station & in Guard’s journal.
6. Review – every 30 days; extension beyond 6 months needs PHOD & CE concurrence.

7. Record Keeping

• SR Register – at every station; page numbered & audited quarterly.
• CO file – retained for 1 year.
• Speed Certificate file – retained for 3 years or permanent if converted to PSR.

8. Do’s & Don’ts for Candidates

✔ Do remember: “ sanctioned ≥ booked ≥ actual ”
✔ Do quote exact km/h from SOD when asked about curves, points.
✘ Don’t confuse “permanent” with “temporary” – PSR printed in WTT; TSR in CO.
✘ Don’t mix bridge restriction (generally 75-110 km/h) with turnout restriction (15-50 km/h).

9. Quick-Fire Facts

• Highest PSR in India: 160 km/h on Tughlakabad–Agra (WR) – 199 km.
• Longest continuous TSR: 30 km between Karjat–Lonavala ( ghat, wet-weather 55 km/h ).
• Only section with 200 km/h trial: Mumbai–Ahmedabad (but under NR; not yet operational).
• Minimum radius for 160 km/h: 1,750 m (transition length 120 m).
• Maximum cant deficiency allowed for BG: 100 mm (125 mm with CMS crossing & 160 km/h).

10. Practice MCQs

1. The maximum validity of a Temporary Speed Restriction (TSR) without extension is A) 3 months B) 6 months C) 9 months D) 12 months

   Show Answer

   Correct Answer: B Explanation: As per SOD 4.05, a Temporary Speed Restriction remains valid for a maximum of 6 months unless a formal extension is processed.

2. Who is the competent authority to countersign a Speed Certificate? A) ADRM B) Sr. DEN (Coordination) C) Sr. DOM (Senior Divisional Operations Manager) D) DRM

   Show Answer

   Correct Answer: C Explanation: The Senior Divisional Operations Manager (Sr. DOM) is the authorized official to countersign Speed Certificates within a division.

3. A 1-in-12 ordinary turnout on BG has a Permanent Speed Restriction of A) 10 km/h B) 15 km/h C) 30 km/h D) 45 km/h

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   Correct Answer: B Explanation: Standard 1-in-12 ordinary turnouts on Broad Gauge are restricted to 15 km/h in the facing direction for safety.

4. The minimum radius for running trains at 160 km/h on BG is A) 1,200 m B) 1,500 m C) 1,750 m D) 2,000 m

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   Correct Answer: C Explanation: To maintain stability and passenger comfort at high speeds of 160 km/h, the minimum curve radius required is 1,750 metres.

5. Which of the following is NOT found in the Working Time Table (WTT)? A) Inter-station distances B) Permanent Speed Restrictions (PSR) C) Temporary Speed Restrictions (TSR) D) Sectional capacity

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   Correct Answer: C Explanation: Temporary Speed Restrictions (TSR) change frequently and are notified via caution orders; they are not listed in the permanent Working Time Table.

6. The first section in Indian Railways to be sanctioned for 130 km/h was A) Mumbai–Pune B) Delhi–Agra C) Howrah–Delhi D) Chennai–Bengaluru

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   Correct Answer: B Explanation: The Delhi–Agra section was the first to receive sanction for 130 km/h operations in 1988.

7. For pollution control under GRAP-IV, a TSR of ___ km/h is imposed in Delhi-NCR. A) 60 km/h B) 75 km/h C) 80 km/h D) 100 km/h

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   Correct Answer: C Explanation: Under high-level pollution alerts (GRAP-IV) in the Delhi-NCR region, a speed restriction of 80 km/h may be imposed to mitigate environmental impact.

8. The colour of the “pink” copy of a Speed Certificate is retained by which department? A) Operating B) Mechanical C) Engineering D) S&T

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   Correct Answer: C Explanation: In the multi-copy distribution of Speed Certificates, the pink copy is traditionally retained by the Engineering department for their records.

9. Maximum cant deficiency permitted for 160 km/h on BG is A) 75 mm B) 100 mm C) 125 mm D) 150 mm

   Show Answer

   Correct Answer: C Explanation: With the use of CMS (Cast Manganese Steel) crossings, a higher cant deficiency of 125 mm is permitted for 160 km/h operations.

10. If TQI (Track Quality Index) value exceeds 65, the imposed speed restriction is A) 10 km/h below sanctioned speed B) 20 km/h below sanctioned speed C) Immediate stop D) 30 km/h fixed speed

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    Correct Answer: B Explanation: Poor track quality indicated by a TQI over 65 necessitates a speed reduction of 20 km/h below the normal sanctioned speed of the section.

11. Which train was introduced in 1969 with 120 km/h booking speed? A) Shatabdi Express B) Rajdhani Express C) Deccan Queen D) Frontier Mail

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    Correct Answer: B Explanation: The Rajdhani Express, introduced in 1969 between New Delhi and Howrah, was the first train to have a booking speed of 120 km/h.

12. The record-keeping period for a Speed Certificate that has been converted to PSR is A) 10 years B) 25 years C) 50 years D) Permanent

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    Correct Answer: D Explanation: Once a speed certificate becomes a Permanent Speed Restriction (PSR), the associated documentation must be kept permanently.

13. Speed restriction imposed during KAVACH commissioning phase is A) 10 km/h for 30 days B) 20 km/h for 15 days C) 30 km/h for 7 days D) 50 km/h for 10 days

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    Correct Answer: A Explanation: During the initial commissioning and testing phase of the KAVACH system, a speed restriction of 10 km/h is typically imposed for a 30-day period.

14. The highest operational PSR (Permanent Speed Restriction) on Indian Railways at present is A) 130 km/h B) 140 km/h C) 150 km/h D) 160 km/h

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    Correct Answer: D Explanation: The Tughlakabad–Agra section currently supports the highest operational speed on the network at 160 km/h.

15. Non-compliance of a notified speed restriction is treated as which category of SPAD? A) Category A B) Category B C) Category C D) Category D

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    Correct Answer: A Explanation: Signal Passing At Danger (SPAD) Category A includes serious safe-running violations, such as ignoring notified speed restrictions.

16. The pilot digital module for online TSR feeding is called A) Rail-Cloud B) DSRM (Digital Speed Restriction Module) C) e-Caution D) TMS-Speed

    Show Answer

    Correct Answer: B Explanation: DSRM is the digital platform developed for the real-time feeding and management of Temporary Speed Restrictions.

Last Updated: January 2026