Depending on the circumstances, control measures will include: Engineering measures:
o Maintaining high levels of ventilation to keep airborne concentrations and
exposures to an acceptable level.
o Enclose the drilling fluid systems to reduce emissions into the air.
o Use bulk handling systems to eliminate the need to handle the fluids manually. o Use of sensors inside the fluid tanks to monitor levels and carry out other
measurements, instead of having to open the tank and visually inspect them. Administrative controls:
o Work overalls and clothing should be cleaned regularly and thoroughly to
remove all traces of drill mud contamination. Dirty clothing is a regular source of skin irritation.
o Regular washing and moisturing of the skin. This will remove contaminants,
and using skin moisturisers will keep the skin hydrated and healthy. The use of barrier creams can also provide a barrier between the skin and low level
exposure to fluids.
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2.22 - Properties, Hazards, and Control Measures of Drilling Muds.
the length of time they are exposed to the hazard. While this will expose more people, the overall exposures of each person will be much lower.
o Health surveillance programmes are necessary to monitor the condition of
employees' skin and their pulmonary function.
o Deliver training and raise awareness of the hazards and the controls to be
followed. The information on Material Safety Data Sheets should be
communicated to all relevant personnel. This will include the hygiene and PPE requirements to be followed.
o Emergency spillage procedures so that in the event of an accidental release
there is a method of cleaning and collecting the fluids while minimising exposure.
Personal Protective Equipment:
o The use of protective clothing is advised to prevent direct contact with
chemicals. PPE may include chemical splash goggles, appropriate chemical- resistant impermeable gloves, rubber boots, and coveralls.
o If ventilation is not adequate it is recommended that goggles and self-
contained respirators are worn at all times. Respiratory protective equipment (RPE) is considered to be a last resort. RPE should only be considered when exposure cannot be adequately reduced by other means. It is vital that the RPE selected is adequate and suitable for the purpose. It should reduce exposure to as low as reasonably practicable, and in any case to below any applicable
occupational exposure limit or other control limit. To make sure that the
selected RPE provides adequate protection for individual wearers, fit testing of RPE including full-face masks, half-face masks and disposable masks is strongly recommended. This will help to ensure that inadequately fitting face masks are not selected.
2.23 - Properties, Hazards and Control Measures of Sludges (including LSA material).
During the drilling process, Naturally Occurring Radioactive Material (NORM) flows with the oil, gas, and water mixture, and accumulates in scale, sludge, and scrapings. These NORMs include:
Uranium. Thorium. Radium. Lead 210.
Oil and gas were created in the Earth's crust by the decay of sea life in ancient seas and are, therefore, often found in aquifers which contain salt water (brine). Various minerals, as well as radioactive elements, are also dissolved in the brine and these separate out and form
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2.23 - Properties, Hazards and Control Measures of Sludges (including LSA material).
wastes at the surface. These include: Mineral scales inside pipes. Sludges.
Contaminated equipment or components. Water.
The process of hydrocarbon extraction exposes the environment and workers to the radioactive elements contained in the sludges. As such, they are classified as hazardous. They can be found in the following locations:
On the drill string.
Inside vessels and tanks. Inside filters.
In coolers where tubes might be coated with sludge.
Hazards.
Sludges are a mixture of liquid and suspended material, and therefore present a range of hazards:
Skin irritation, and possibly dermatitis.
Inhalation of the fumes or dusts from dried sludges.
Ingestion, through poor hygiene practices such as not washing, not cleaning up, eating at work site).
Exposure to radioactive substances and carcinogens.
The main hazard of exposure to ionising radiation from LSA materials is that of the
inhalation and ingestion of radionuclides, especially of dust and fumes. Employees are at a higher risk of significant exposure to ionising radiation if they work with dusty processes unless adequate control measures have been put in place to prevent the inhalation of dust. Employees may be exposed, although to a lesser extent, to direct radiation where there is bulk storage of the material. They may also be exposed to external radiation if they are involved in cleaning operations or the dismantling of equipment which contains scale from oil and gas extractions.
Control Measures.
Employers should put in place controls to ensure that the risk of exposure to ionising
radiation is reduced 'so far as is reasonably practicable'. The use of PPE may be used only as a last resort after all other control measures have been considered. Engineering controls
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2.23 - Properties, Hazards and Control Measures of Sludges (including LSA material).
and the implementation of safe systems of work should take priority, and they include: The provision of ventilation equipment to contain dusts and fumes.
The use of wet methods of working and good housekeeping to reduce the amount of dust in the atmosphere.
Having equipment in place to collect sludge instead of using manual means. Diluting sludge with water.
The use of permit-to-work systems. especially if the concentrations of dust or fumes reach a level where only designated persons are allowed to work under the
restrictions of written safe system of work.
The provision of training and awareness programmes.
The provision of a health surveillance programme to monitor the health of employees.
Good supervision to ensure that everyone follows the necessary control measures. Good hygiene practices, including washing before eating, drinking, or smoking, and
keeping work clothes clean.
The use of respiratory protective equipment specifically chosen to protect against exposure to airborne radioactivity.
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2.23 - Properties, Hazards and Control Measures of Sludges (including LSA material).
Figure 1. Photo of an employee in full PPE following a tank sludge cleaning operation.
Question 4.
Is the below statement true or false?
The higher the flash point, the greater the potential fire hazard.
Question 5.
Select the correct missing word to complete the below statement. _____ designates liquids with a flash point below 21°C.
Question 6.
Select the correct missing word to complete the below statement.
When Nitrogen concentrations increase (e.g. when purging equipment) and the oxygen levels drop below _____, rapid suffocation can occur.
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2.24 - Example Exam Questions on Hazards Inherent to the Oil and Gas Industry.
Here is a small selection of past exam questions on recent sections. It is unlikely that you will be asked these questions at your exam. But you may be asked similar questions, and therefore this is an opportunity for you to familiarise yourself with types of questions NEBOSH ask at Certificate level.
1.
(a) Outline the term Flash Point. (3)
(b) Identify the Hazards associated with LNG. (4) 2. Give the meaning of the following terms: (a) upper flammable limit (UFL); (2)
(b) lower flammable limit (LFL); (2) (c) flashpoint; (2)
(d) Highly flammable liquids. (2)
3. Following preparation of a vessel for maintenance within an oil and gas installation a low specific activity (LSA) radioactive sludge was encountered.
(a) Identify hazards associated with the sludge. (2)
(b) Outline control measures to reduce the risk to workers exposed to the sludge. (4)
(c) Identify TWO other pieces of workplace equipment where the sludge may be found. (2) 4.
(a) Identify properties of hydrogen. (4)
(b) Outline hazards associated with hydrogen. (4) 5.
(a) Identify properties of nitrogen. (4)
(b) Outline hazards associated with nitrogen. (4) 5.
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2.24 - Example Exam Questions on Hazards Inherent to the Oil and Gas Industry.
(a) Identify properties of Hydrogen Sulphide. (4)
(b) Outline hazards associated with Hydrogen Sulphide. (4) 6.
(a) Identify properties of Methane. (4)
(b) Outline hazards associated with Methane. (4) 7.
(a) Identify properties of LPG. (4)
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2.25 - Summary.
The learning outcome for this section was:
2.0 - Explain the hazards inherent in oil & gas arising from the extraction, storage and
processing of raw materials and products. In this section we have learnt:
About various physical properties such as flash point, vapour density, vapour pressure and flammability limits etc.
About the hazards and risks of various hazardous gases and substances such as LPG, LNG, methane, hydrogen, hydrogen sulphide, mercaptans, water, drilling mud, low specific activity sludge etc.
About related control measures for the above hazards.
3.0 - Risk Management Techniques Used in the Oil and Gas Industries.
The learning outcome for this section is:
3.0 - Outline risk management techniques used in the oil & gas industries.
In this section we will provide an overview of risk management techniques. In particular we will discuss:
The purposes and uses of risk assessment techniques. Qualitative and quantitative techniques.
How risk management tools are applied in process safety risk identification and assessment.
How they are applied in project phases from concept, design and start-up. The concept of 'as low as is reasonably practicable'.
The management of major incident risks.
Industry related process safety standards, inherent safe and risk based design concepts, engineering codes and good practice.
The concept of hazard realisation.
The concept of risk control using barrier models.
The use of modelling for risk identification, such as thermal radiation output and blast zones.
3.1 - The Purposes and Use of Risk Assessment Techniques.
Employers in each workplace have a general duty to ensure the safety and health of
workers in every aspect related to their work. The purpose of carrying out a risk assessment is to enable the employer to introduce control measures necessary for the safety and
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3.1 - The Purposes and Use of Risk Assessment Techniques.
health protection of workers.
Whilst the purpose of risk assessment includes the prevention of occupational risks, and this should always be goal, it will not always be achievable in practice. Where elimination of risks is not possible, the risks should be reduced and the residual risk controlled. At a later stage, as part of a review programme, such residual risk will be reassessed and the
possibility of elimination of the risk, perhaps in the light of new knowledge, can be reconsidered. In the oil and gas industry it will be necessary to identify risks related to plant, equipment, products, processes, and systems of work. All of these have the potential to cause harm.
The UK Health and Safety Executive states that a risk assessment is "a careful examination of what, in your work, could cause harm to people, so that you can weigh up whether you have taken enough precautions or should do more to prevent harm".
There are a number of techniques available when assessing risks, including: The HSE's 5 Steps to Risk Assessment approach.
Qualitative assessment techniques.
Semi-quantitative assessment techniques. Quantitative assessment techniques.
We will learn more about these in the following sections.
Before we progress further, it is important to define what is meant by 'hazard' and 'risk'. A hazard is defined as something with the potential to cause:
Harm, including ill-health and injury.
Damage to property, plant, products or the environment. Production losses or increased liabilities.
A risk is defined as the likelihood that the harm will occur. It is the chance, high or low, that a person could be harmed or some infrastructure could be damaged. This is usually
accompanied by an indication of how serious the harm could be.
It is commonly considered that risk is the combination of the likelihood of a hazard causing harm, and the potential severity of that hazard.
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3.1 - The Purposes and Use of Risk Assessment Techniques.
In other words: