PERMIT TO WORK SYSTEM (PTW)
SREKUMAR KONDAYIL GM(E)
-
WORK PERMIT
•ONGC based on OISD STD 105
•OMR 2017 (Reg 89/99/131)
•SMP
•HSE MANAGEMENT MANUAL
OISD
•1986
STD 105
•1988
•1998
•2004
MoP&NG constituted a Safety
Council assisted by OISD
PUBLISHED
AMENDED
FIRST REVISED
PTW
COLD
CONFINED
ENTRY
HOT
VEHICLE
ENTRY
ELECTRICAL
EXCAVATION
PURPOSE
• To ensure that work is carried out in
the safest possible manner
• To prevent injuries to personnel
• Protect property from damage
• Avoid fire etc
COLD WORK
HOT WORK
• An activity which does not produce
sufficient heat to ignite a flammable air
hydrocarbon mixture
• An activity that can produce a spark or
flame or other source of ignition
having sufficient energy to cause
ignition, where the potential for
flammable vapors, gases, or dust exists.
COLD WORK PERMIT
COPY
•TWO COPIES
COLOUR
•ORIGINAL YELLOW
WHERE
• Opening process of machinery
• Blinding & de-blinding
• Tightening of flanges, Hot bolting
• Inspection, painting, Grass cutting etc
HOT WORK PERMIT
COPY
•THREE COPIES
COLOUR
•ORIGINAL PINK
WHERE
• Welding, grinding, gas cutting, burning,
soldering, chipping
• Excavation, open fire, use of certain nonexplosion proof equipment
• Entry of Petrol / Diesel driven vehicles in
hazardous process area
EXCAVATION/CONFINED SPACE (OISD 192 checklist)
EXCAVATION
• PERMISSIONS (INST/ELECT/PROCESS)
CONFINED
• Excavation more than 1.2 M,
• Entry on Floating roof Tank ht>3 mt
• U/G channels, pits
• Enclosed area, restricted entrance &
exit
When to allow inside??(CONFINED)
• combustible gases are up-to 5% LEL
• Entry with an air-supplied mask permitted with
LEL of upto 20%
• The oxygen level at least 19.5 % vol
• Toxic gases below the threshold limits.
Threshold Limits of Natural Gas
S.No.
Methane
MIE
LEL in % by
volume of Air
5.0
Methane
UEL in % by
Auto ignition
volume of Air temperature
15.0
580°C
0.21 mJ @ 8.5% by volume
Electrical Isolation & Energisation Permit
•
Before issuing any work permit, it is essential to isolate electrical
power to the extent necessary.
• Section-A
Electrical isolation
• Section-B
for Energisation
• Colour: Different from others.
LOTO SYSTEM
•
•
Isolation of energy
Avoid accidental operation
Work at height
• More than 2.2 meters, ISI approved full body
harness shall be used.
• More than 2.2 meters, permit should be issued
General Guidelines
• Plot plans with red pins in C/R
• suspend work at any point of time.
• Stop work/Cancellation of permit when emergency
alarms ON
• Radiography with X-ray machine shall be carried out
under Hot work permit
• Cold work permit may be used if it is done with radioactive isotopes.
Tool Box
Talks
Job Safety
Analysis (JSA)
• Documented safety meeting in
local language
• Before start of day’s work
• Categorize work into small works
• Identify potential hazards &
recommend safe approach
PERMIT EXTENSION
• Only for a single shift.
• Extended shift wise for a period not exceeding seven
calendar days
HOW LONG TO KEEP A PERMIT (PRESERVE)
• 3 MONTHS
PERMIT TO WORK – BEST PRACTICE
TOOL BOX TALK & JSA
PTW – COLD/HOT
PERMIT ISSUE REGISTER (C/R)
ISOLATION CERTIFICATE
ENTRY IN LOTO REGISTER /LOCK & TAG
CROSS LINKING /CHECK & SIGN PTW
ORIGINAL TO RECIPIENT