INCIDENT 1Date - 5th August 07Location - Workshop in Nongbon, ThailandIncident - A furnace module to be sent to Nigeria

was being fabricated. The company was doing a pneumatic coil test at approximately 100 bar. An employee from other project was walking pass the pressure test area. The testing flange blew off and struck the employee on the head.

The area around the pressure test had not been identified in any way.

Area not barricade. No warning signage. No standby person keeping watch to warn passers-

by. There had been no general warning of any testing

taking place.

Built in 1978-1979

Chernobyl

Reacktor Bolshoy Moshehnosty Kipyashiy

RBMK, a Russian acronym translated roughly means “reactor cooled by water and moderated by graphite”

The Control Rods: long metal rods which, in the Chernobyl reactors, contain boron; they help control the chain reaction

1. As the reaction occurs, the uranium fuel becomes hot

2. The water pumped through the core in pressure tubes removes the heat from the fuel

3. The water is then boiled into steam4. The steam turns the turbines5. The water is then cooled6. Then the process repeats

01:00 The preparation for the test 13:47 Lowering of the reactor power

halted at 1,600 MWt 14:00 The ECCS was isolated 23:10 The power reduction resumed

24:00 Operation shift change 24:28 Power level is now 500 MWt and

kept decreasing to 30 MWt 24:40 The operator withdrew some

control rods 01:00 Power had risen to 200MWt 01:03 Connecting the fourth main

cooling pump to the left loop of the system 200MWt

01:07 Connecting the fourth main cooling pump to the right of the loop system - this was a violation of NOP

01:19 Increased feed water flow to the steam drums and removed more control rods -violation of NOP

01:23 The test was started 01:23:10 Automatic rods withdrawn from

the core 01:23:21 Two groups of automated

control rods were back to the core

01:23:30 Power kept increasing 01:23:40 Emergency button pushed 01:23:44 Power is at 300000 MWth 01:23:48 1st thermal explosion 01:23:55 2nd explosion

0

200

400

600

800

1000

1200

1400

1600

1800

3:47:00 0:28:00 0:40:00 1:00:00 1:03:00

Series1

0

50000

100000

150000

200000

250000

300000

350000

Series1

31 employees and firefighters died

134 emergency workers suffered from acute radiation sickness

By the year 2000 there were 1800 case of thyroid cancer in children and adolescent

High number of suicide and violent death among Firemen, policemen, and other recovery workers

Use of graphite as a moderator Lack of a well-built containment structure Inadequate instrumentation and alarms

for an emergency situation There were no physical controls that

prevented the operators from operating the reactor in its unstable state

Isolation of the emergency core cooling system

Unsafe amount of control rods withdrawn Connection of the four main cooling

pumps to the right and left of the system

Mental model The operator did not have a good mental

model of the system itself Overconfidence

By having an electrical engineer on site for an electrical test

No confirmation of cues obtained from the system

Beta too high Many missed signals before the accident

Have proper Standard Operating Procedures (SOP) for both normal and emergency situations

Have scheduled trainings and practices for normal and emergency situations

Always have a reactor expert on site Have operators confirm any cues from

the system before making hypothesis or take action

Have a team work kind of environment such that every body is involved

Worst industrial disaster in history 2,000 people died on immediate

aftermath Another 13,000 died in next fifteen

years 10-15 persons dying every month 520,000 diagnosed chemicals in

blood causing different health complications

120,000 people still suffering from Cancer Tuberculosis Partial or complete blindness, Post traumatic stress disorders, Menstrual irregularities

Rise in spontaneous abortion and stillbirth

ICMR, IMA, AMA studies show Children born with genetic

defects Growth retardation in boys Hormonal chaos among girls

Ground water contamination with high level of mercury, lead, nickel, VOCs and HCH

High prevalence of skin and gastro-intestinal diseases

Bioaccumulation of toxins found in vegetables and breast milk

December 3-4, 1984: 40 tonnes of methyl iso-cyanate (MIC) released from Union Carbide plant at Bhopal

Accidental release caused by leakage of water into MIC storage tank

None of the six safety systems worked

Safety standards and maintenance system ignored for months

Complete absence of community information and emergency procedures

Public alarm system operated after the gas had leaked for nearly four hours

THE END