INFRINGING
STANDARD MOVING DIMENSIONS (ISMD) or OVER
DIMENSIONAL CONSIGNMENT (GR/SR 4.28)
Standard moving dimension measurements are prescribed by the Railway
Board for safe movement of consignment loaded in wagons.
It is classified based on the clearance from the
fixed structure.
Gross
Clearance: Means the physical clearance at rest.
Net
Clearance: Means the
minimum clearance on run.
Class-A (Permitted
out of Guage loads)
Ø Gross clearance more than 9” and net clearance more than 6”.
Ø Sanctioning authority is ‘DRM’ within divisions and ‘COM’ beyond two
divisions and movement permitted both during day and night.
Ø Escort is not necessary.
Ø Speed limit- 75 kmph in normal case 30 kmph near fixed structures.
Class ‘B’
(Exceptional out of Guage loads)
Ø Gross clearance is between 6”and 9” and Net clearance between
3” to 6”.
Ø Sanctioning authority is CE.
Ø Normally permitted during day and with precautions during night also.
Ø Speed limits 40 kmph.
Ø Escorting officials TI, SE/P-way, SE/C & W, Signal Inspector are required.
Class ‘C’ (Extra
ordinary out of Guage loads)
Ø Gross clearance less than 6”and net clearance less than 3”.
Ø Sanctioning authority CRS and permitted only during day.
Ø Speed limit 25 kmph
Ø Escort is required.
Precautions to be taken while carrying
ISMD.
Ø It shall be marshaled next to Train engine.
Ø It shall be moved only by through goods trains.
Ø If no through goods trains on run it may be attached to shunting trains with
specific instructions to the staff of all stations enroute.
Ø Loose shunting against such loads is strictly prohibited.
Ø Escort staff shall
be arranged according to the Class by C & W department, Engineering
department, OHE department etc.
Ø Trains carrying ISMD should be dealt only on the lines nominated in the
station working rules at stations.
Ø Normally these trains shall be dealt on non platform lines.
Ø When dealt on PF lines speed shall be restricted to 5 kmph.
Ø Escort staff to inspect the loads at frequent intervals to ensure that
the position of the loads is not shifted during run.
Ø Change of route and diversion is not permitted.
Precautions to
be observed in 25 KV electrified sections
Ø If Gross Clearance is more than 390mm- No speed limits.
Ø If Gross Clearance is between 340mm and 390mm speed limit is 15 kmph.
Ø If Gross Clearance is less than 340mm-speed limit 15 kmph and OHE power
supply to be switched off.
Ø If Clearance is Less than 100mm-No movement permitted.
