In the present global industrial scenario, where a fatal mistake can be catastrophic, safety is important especially in high risk areas such as
nuclear, aircraft, chemical, oil and gases, and mining industries, as it
safeguards human life. Industrial Safety reduces risks to people, and
processes?. Usually, process control and safety systems are merged. It is not
only an important human resources issue to maintaining a safe and healthy
working environment , it’s the law. The employees need to understand health and
safety risks, whether they’re entry-level workers, seasoned veterans,
supervisors, or plant managers, the steps they need to take to minimize those
risks, and common safety standards and compliance procedures.
It is necessary to inculcate safety culture, for
any industry to be successful. The significance of Safety & Health in
chemical industries in achieving productivity and an edge in the competitive
world has been a vital issue. Therefore, it is an urgent task to establish a
systematic approach to safety in the use of chemicals at work.
A chemical plant is
an industrial process usually on a large scale that manufactures or processes chemicals. The objective of a chemical plant is generally to
create new material via the chemical or biological transformation or separation
of materials. Specialized equipment are used by the chemical plants which are units,
and technology in the manufacturing process. Other kinds of plants, such as
polymer, pharmaceutical, food, and some beverage production facilities, power
plants, oil refineries or other refineries, natural gas processing and biochemical plants, water and wastewater treatment,
and pollution control equipment
use many technologies that have similarities to chemical plant technology such
as fluid systems and chemical reactor systems
1.2.Importance of safety in chemical plant
The chemical industry creates a huge variety of products
which impacts on virtually every aspect of our lives.
Safety must be considered as the top agenda for the chemical
industry’s. During their manufacturing and transportation many of its products
are potentially hazardous. These chemicals could be solids, liquids or gases,
flammable, explosive, corrosive or toxic. The industry operates within the
safety limits demanded by national and international legislation, since the manufacturing
processes frequently involve high temperatures, high pressures, and reactions which
can be dangerous unless carefully controlled and monitored.
Safety becomes first and the foremost considerations due to
the following reasons:
protects workers, employers and all people in the plant including
strangers from illness, injuries or death.
survival of company’s business.
prevents company’s property and facility from damage.
enhances company’s reputation.
teaches people in the plant how to work safely.
helps company to achieve its targets and objective.
company away from law suits and penalties..
will be avoided from unnecessary cost.
keeps workers awareness alive.
teaches everyone in the plant to pay attention to their workplaces and
keeps customer’s confidence to do business with the company.
program is a cost-effective decision for the company.
is able to reduce employee’s turn over and increase productivity.
can prevent production process interruption and shut down.
1.3. Category of chemical plants
Agriculture is the
back-bone of the Indian economy, and hence, the very existence of economic
activities of entire people in the country is dependent on the state and health
of its agriculture sector.
Since last 30 years, the
fertilizer industry in India has grown tremendously. The fertilizer industry in
India consists of three major players; The Government owned Public Sector
undertakings, Cooperative Societies like KRIBHCO, IFFCO and units from Private
fertilizers give growing plants the nutrients they crave in the form they can
most readily absorb and use: nitrogen (N), available phosphate (P) and soluble
Refineries and Petroleum Industry
Oil refinery or
petroleum refinery is an industrial process plant where crude oil is
transformed and refined into more useful products such as petroleum naphtha,
gasoline, diesel fuel, asphalt base, heating oil, kerosene, liquefied petroleum
gas, jet fuel and fuel oils.
Oil refineries are typically large, sprawling industrial complexes with
extensive piping running throughout, carrying streams of fluids between large
chemical processing units, such as distillation columns. In many ways, oil
refineries use much of the technology of, and can be thought of, as types of
Pesticide is an all-inclusive term of pesticide, herbicides, weedcides
etc. The pesticide includes a variety of organic and inorganic compound but the
modem trend is towards the synthetic organic pesticide.
Pesticide includes both organic and inorganic material. Inorganic
pesticides include compounds of leads, arsenic, mercury chlorine, HCN, lead-
arsenate, sodium arsenite. etc. Examples of naturally occurring pesticides are
rolenone, phrethrin, nicotine and petroleum derivatives, DDT, BHC, Chloride,
Methoxychlor, Aldrin etc. are the example of synthetic organic pesticide.
iv. Electroplating and Heat Treatment Industries
of metals produce waste containing metal ions such as chromium, nickel,
cadmium, silver, gold etc. The volume of waste-water discharged from plating
industry is small but toxic.
v. Hydro-Generated Oil and Soap Industries
manufacture of soap a strong waste known as spent soap lye is discharged by the
industry. The lye consists of sodium salt of fatty acids which do not
crystallized out in the process. It is highly alkaline and exerts very high BOD
& COD values.
Inorganic and Organic Chemical Industries
of acids, alkalies, allied chemicals and salts are clubbed in to this industry.These
industries are classified into two broad groups:
The composition of waste-water from a synthetic
drug factory producing anti-pyretics, sulphur drugs, antitubercular drugs and
More than two thousand deaths from a methyl isocyanate
chemical leak in Bhopal, India, drew world attention to serious hazards in the
chemical industry. Following that tragedy, the Occupational Safety and Health
Administration (OSHA) developed guidelines to aid employees in reducing the
number of potential hazards in chemical industries.
It is important to draw attention towards the chemical
industry and safety precautions to guard against chemical disasters.
There are three tasks
to perform before any meaningful analysis of an emergency response system can
begin. The first The first task is to identify the key processes and elements
of the production process and to understand how operational processes are kept
within safe bounds under normal conditions. Conceptually, it is the normal
process instrumentation and control measures that provide the first and
greatest degree of protection to plant employees and to the public. The four
areas listed below identify some major subsystems or components which are
commonly found in chemical plants. Each has a bearing on the safety of
operations under normal and emergency conditions.
A management subsystem which includes management personnel, process
specifications, plant design, standard operating procedures, and the written
A personnel subsystem which assigns and defines roles, for both normal
and emergency operations, and provides appropriate training. This may also
include labor/management safety committees.
A physical subsystem which may include transportation systems for
materials, ventilation systems, waste removal systems, containment systems,
refrigeration systems, storage areas, communications systems, and other process
An emergency services subsystem including plant and community
A second task is to understand how critical failure points
are identified, and what controls are used to ensure safe operations.
The third task is to identify the emergency response system
that is embedded in the operating system.
All the planning and preparation of safe plant operation is
meaningless, unless it can be implemented. In the event of a problem, there is
no time for committee or front office decisions. Correct decisions have to be
made at the lowest organizational level possible, and those decisions have to
be communicated to other affected personnel
It is obviously to see the physical plant and to relate
information contained in operating procedures, emergency plans, and blueprints
with actual structures, materials, and processes.
Plant layout has some
specific safety aspects.
Separation and isolation
Chemicals which may react
with one another are to be physically separated, oxidizers are to be
stored in areas remote from fuel storage.
Areas of potential
explosions storage of explosives, reaction vessels are to be isolated so
if there is an explosion, the damage and risk to employees is minimized.
Where hazardous liquids may
leak or spill from piping or vessels, provisions are made to prevent
their spread to areas where employees may be exposed to the hazard.
Examples of possible methods include grading.
Provisions are made to control
unexpected hazardous vapor or gas releases within the drain lines.
§ Work areas are
supposed to be well maintained.
Some processes which are
safe in open air may become hazardous if enclosed. If areas of potential
or frequent leaks or spills are enclosed to prevent environmental
contamination or the spread of the chemicals, there has to be adequate
precautions to protect employees. Examples include ventilating the room
and treating the exhaust; automatically sampling the air in the room or
vault; having employees sample before entering the room.
two factors should be considered in materials selection: First, the contaminate
or cause of reaction in the chemicals to be handled or processed. Second, does
the chemicals to be processed attach or destroy the equipment. For all chemical
processes, there are preferred materials; preferences sometimes are economic,
and sometimes they are based on chemical reactivity or compatibility. The
intent here is to identify readily available materials that might be used but
that are incompatible with the chemicals involved.
reactive chemicals may have their reactions catalyzed by common materials which
easily enter systems whenever seals are opened. Examples include water or rust
which may easily enter a system during transfer from one vessel to another,
either during hookup or disconnect, or during pressurizing or venting of tanks.
When systems are opened for maintenance
purposes, precautions are taken to prevent contamination. It is done to
safeguard the system while it is open. Precautions are taken to ensure that
replacement parts are free of contaminants incompatible or incompatiable
materials. When connections are made and broken (e.g., during transfer from
rail cars or trucks), measures are taken to ensure contaminants do not enter
equipment must be shut down sometime. When safety systems are shut down, backup
systems or procedures are available to provide replacement protection.(e.g.,
stop process until safety systems are available again). If shutoff valves can
isolate safety relief valves, measures ensure that the system is protected from
over-pressurization (e.g., person stationed to monitor pressure)
Pressure vessels also need periodic inspection
and testing because of normal wear and potential corrosion either at welds or
in the base material. The combination of pressure and volume determine the
hazard: high volume, low pressure systems can have the same potential energy
for release as low volume, high pressure systems.
When potentially corrosive chemicals are used
(e.g., acids, caustics), or the plant atmosphere is corrosive (e.g., near the
ocean, or from chemical releases within the plant), measures are taken to
ensure system integrity. Examples include periodic pressure testing, x-ray,
As long as
chemicals are maintained in a closed system, they are safe and harmless.
Chemical processes using hazardous chemicals should be designed to maintain
that closed system. After design and maintenance, the only potential problems
are: introduction of raw into the closed system and the removal of products
(either the desired product for shipment or waste) from the closed
Suitable controls and instruments should be
provided for both normal conditions of operation and for emergencies.
Instrumentation includes sensors, indicators, recorders, and transmitters for
measurements such as temperature, pressure, flow, liquid level, and analysis.
Many self-acting control devices, such as
pressure regulators, normally fail in the open position, which may be the
unsafe position. In such cases, emergency backup controls should be provided.
In the case of pressure regulators, this includes pressure relieving devices
down-stream and automatic shutoff valves interlocked with excess pressure switches.
Response to Emergencies
Assessing the adequacy of a written
emergency plan is an art. It involves judgment as to the reasonableness of the
assumptions underlying the plan (e.g., what is a reasonable worst-case estimate)
as well as the adequacy of countermeasures designed to protect life and to
limit environmental and property damage.
A few general principles may be useful in approaching this task:
The priorities of the plan
clearly stated as to — safety of plant personnel and the public, control
of hazard and minimizing damage to property.
Plan deal with reasonable
Dealing with any type of
emergency. For example, contingencies included for: fire and explosion, release
of highly toxic materials, large chemical spills, sabotage including bomb
The Secretary of Labor has said that “the cornerstone of any successful,
effective safety and health program is accurate and complete recordkeeping.”
Because of its importance, OSHA places special importance on recordkeeping.
Employers of 11 or more employees must maintain records of occupational
injuries, illnesses and deaths as they occur. The purposes of keeping such
records are to inform employees of the effectiveness of their employer’s safety
and health program, to permit the Bureau of Labor Statistics to complete survey
material, and to help define hazardous industries.
Initial and periodic monitoring, including the date of measurement, operation
involving exposure, sampling and analytical methods used and evidence of their
accuracy: number, duration, and results of samples taken, type of respiratory
protective devices worn,and name, social security number, and the results of
all employee exposure measurements. This record should be kept for 30 years.
Employee Training:These records should be kept for one year beyond the last
date of employment by that employee. All records should be made available, upon
request, to the OSHA Assistant Secretary, the Directory of NIOSH, affected
employees, former employees, and designated representative.
2.1. Rules and regulations
According to the
EPA, the rules aim to:
accidents by improving accident prevention program requirements.
preparedness to ensure coordination between facilities and local
Improve information access
to help the public understand the risks at the facilities.
Improve third-party audits
at such facilities.
General Plant Safety and occupational health policy
Objective: Zero Injuries, Illnesses and Incidents
will be operated in a condition that will not risk incurring injuries or
illnesses to personnel, adversely affect the health and safety of the community
or negatively impact the environment.
are personally accountable for preventing injury and illness to themselves and
their fellow workers, and for protecting Company assets. Acceptance of this
full safety responsibility, personal alertness and following plant safety rules
is job requirements.
injury/illness, no matter how minor, will be addressed because the employee’s
immediate and future health is a top priority. A minor injury or illness left
untreated increases the potential of becoming a serious health risk to the
General Safety & Occupational Health (S&OH) Rules
injury or occupational illness sustained or even suspected, on plant, must be
reported immediately to the Managing Resource Team Leader, or their designee,
and be examined by Medical.
S&OH incident with or without injury is to be reported to their Managing
Resource Team Leader, or their designee, so the cause can be determined and
preventive action taken.
employee must be familiar with all S&OH Rules and Material Safety Data
Sheets (MSDS) for chemicals used in their assigned area, and understand any
injury or health problem potential inherent in the use or handling of such
wear rings, watches, bracelets, necklaces, and earrings (studs are acceptable)
in all production areas, back maintenance shop, equipment room and designated
areas in technology labs when outside of marked aisle ways.
Site housekeeping standards
individual has responsibility to establish and maintain housekeeping at a high
standard of excellence such that any deviation that might create a hazard or
reflect poor workmanship or poor quality are quickly identified and corrected.
housekeeping and orderliness have positive impacts on safety, product quality,
workmanship, pride, and efficiency. It is a reflection of the safety
environment within the area.
General Equipment Safety Rules
using periodically inspected equipment such as safety harnesses, life lines,
ladders, steam hoses, extension cords, hoists, etc. verify the presence of a
current inspection tape and be sure there are no obvious deficiencies. Tag out
and correct any deficient items.
the condition of any tool or piece of equipment (electrical or non-electrical)
to determine if it is safe to use before you use it. Regardless of condition,
do not use equipment that has an overdue inspection tag.
General hazardous material
hazardous products, or contaminated parts will not be stored in offices or
lockers unless appropriate storage facilities are provided.
liquids more than 16 oz. and all flammable aerosol cans must be stored in a
flammables cabinet after use.
carriers must be used for flammable, toxic, corrosive, or other hazardous
materials or multiple samples in glass containers that are being carried or
Several types of
risks, for example, credit, market, and operational risks are encountered by
chemical companies. In this work, the primary focus is on calculating the
operational risk associated with a chemical company, which is defined as the
risk of direct or indirect losses resulting from inadequate or failed internal
resources, people, and systems, or from external events.
Analysis (HAZOP Study) for a Hazardous Chemical Storage Plant
timing of a hazard and operability study is determined by the objectives of a
study, and in turn determines the benefits that may be gained. The outline
concept of a process may be examined to highlight any major omissions or
significant features. As further detailing is carried out, e.g. when the
process design is complete, the full study procedure may best be applied.
Operating procedures may be examined to ensure that all eventualities have been
hazard operability method is careful examination which is performed by
multi-disciplinary team to collect necessary information related to process so
as to find out all potential hazard involve in the process. HAZOP is
quantitative risk assessment method which can be performed to make sure that
existing design and operating process is safe. It is also performed to improve
safety of existing facility most importantly it is conducted to find out
deviation in typical operation and operational failure.
operability study (HAZOP) method is to identify unexpected deviation while
decanting and storage of toluene and action required reducing risk are
suggested and implemented. The hazard operability study is basically performed
at design stage. It is qualitative analysis and helps to identify the
possibility of failures and consequences
This method helps to identify potential hazard related any system or
process and contributes to recommend control measures.