Oil spills on land and sea happen for many reasons. For example, when pipelines break, containers leak, or refineries explode. They can cause significant damage to the environment and wildlife. Even minor oil spillages can have serious consequences. Because it may take years for some species or sensitive areas to recover from the effects.
Booms are a commonly used tool for spill response in open waters. However, they can also sometimes be a source of confusion. Because it‘s often challenging to know the differences—or advantages—between each type of containment boom.
Well, no longer! In this article we’ll explore four different types of oil booms and how they work. Plus, look at guidelines for selecting the best boom appropriate to water conditions. So, keep reading to find out more about using booms for oil spill containment and clean up.
How Are Oil Booms Used?
Containment booms are designed to encircle and control the spread of oil spills. Be it on a harbour, coastline, marina or other body of water. Oil floats and quickly disperses on the surface of the water. So booms act like a floating barrier or dam to contain, deflect, or divert the flow of oil.
Thus, booms assist emergency response crews to remove oil from the spill area. Which is done with recovery equipment like scoops, vacuums and skimmers. As well as oil absorbent materials or dispersants (chemicals that break an oil slick down into smaller droplets).
Oil spill containment booms may be towed or moored to a structure like a buoy. How the boom is used will depend on the size and location of the spill. As well as how responders plan to clean it up.
Boom reels are often used to store certain shapes or types of booms. They offer a tidy and efficient storage space solution. And also allow for easy transportation and fast boom deployment.
What Are The Parts Of A Containment Boom?
Oil spill containment booms can have quite different appearances. However, they all share the same basic design characteristics and components. Including impermeable materials with high tensile strength, like heavy duty PVC. Often in high visibility colors of yellow or orange that stands out against dark water.
Let’s explore the individual elements of a boom and what each part does:
- The freeboard is the visible barrier that sits above the water. It keeps the oil contained and prevents it from splashing over the top of the boom.
- A draft or skirt extends the freeboard wall below the water’s surface. This flexible part of the boom stops any oil from escaping underneath.
- Floatations, of foam or air chambers, provide buoyancy and prevent the boom from sinking.
- Ballast or chains along the bottom of the draft act like anchors against the above-water floatations. By helping weigh down the boom, they maintain its vertical wall position in the water.
- Horizontal tension cables give the boom strength, stability, and hold its shape. Plus add resistance to forces like wind, waves and water current.
- Lateral connectors or couplings join boom sections together. To create the necessary lengths or perimeter enclosure around a spill. Or for towing a boom through the water, behind a spill response vessel.
Different Types Of Oil Booms
There are several types of booms available for containing spills. With varying shapes, heights and sizes. Each has its own purpose when it comes to the body of water where it will be used. For example, calm waters like small and shallow lakes or ponds. Versus deep water at sea that is subject to strong currents, wind or choppy wave action.
ASTM International provides two guidelines relevant to oil containment booms. They summarize grading of wave height in relation to selecting a boom suitable to the water conditions:
ASTM F625: Classifying Water Bodies for Spill Control Systems
| Type | Wave height (feet) | Condition examples |
|---|---|---|
| Calm water | 0 to 1 | Small, short, non-breaking waves |
| Protected water | 0 to 3 | Small waves, some whitecaps |
| Open water | 0 to 6 | Moderate waves, frequent whitecaps |
| Open water (rough) | > 6 | Large waves, foam crests and some spray |
Strong current direction, the ratio of wave length to height, and orientation should also be taken into account
ASTM F1523: Selection of Booms in Accordance With Water Body Classifications
| Boom property | Calm water | Calm water – Current | Protected water | Open water |
|---|---|---|---|---|
| Freeboard/draft total height (in.) | 6 to 24 | 8 to 24 | 18 to 42 | 36 to 90+ |
| Minimum buoyancy to weight ratio | 3:1 | 4:1 | 4:1 | 8:1 |
| Minimum total tensile strength (lbs.) | 1,500 | 5,000 | 5,000 | 10,000 |
| Minimum fabric tensile strength (lbs./in.) | 300 | 300 | 300 | 400 |
| Minimum fabric tear strength (lbs.) | 100 | 100 | 100 | 100 |
Recommendations for Selection of Temporary-Use Spill Containment Booms
Freeboard should be between 33% and 50% of the total boom height
Four design types of booms for oil spills
1. Inflatable booms
Inflatable booms rely on air chambers for buoyancy. Self-inflating booms work by compression and spring or coil action. They open up and expand by automatically drawing in air through a one-way valve. Whereas manual inflation models require a blower or air compressor to fill them up.
Uses: Inshore or offshore (rough, protected, or calm waters).
Pros: Versatile uses including deep water sea or rivers. Can be anchored or towed. Compact and easy to store or transport on a boom reel. Flat shape is easy to clean.
Cons: Although made from durable materials, they can puncture and deflate. Often more complicated to deploy. Generally the most expensive boom design.
2. Solid Flotation Booms
This style boom uses solid foam-core floats that make them somewhat rigid. The dense foam is usually a flat or cylindrical shape. And is either attached externally to the freeboard or housed inside a pocket chamber.
Uses: Inshore or offshore (sheltered or calm waters like harbours).
Pros: Heavy duty design can stay afloat for long durations. Lightweight to handle. Low to mid-range cost.
Cons: Bulky and require more storage space than inflatable booms. Can be more difficult to clean depending on the float shape.
4. Curtain Booms
One of the most common designs, curtain booms can have either a solid foam or inflatable flotation chamber.
Uses: Inshore or offshore (rough, calm or protected waters).
Pros: High buoyancy to weight ratio so able to perform well in rougher, open water. Lightweight designs provide ease of handling for spill responder crews.
Cons: Booms with foam floatations are bulkier to transport and store. Can be difficult to clean.
3. Fence Booms
A high freeboard and flat flotation design fits this boom‘s fence name. The shape has an obvious contrast to inflatable or rounded-foam float booms.
Uses: Inshore waters (calm or protected).
Pros: Flatter design can be wound onto a reel for easier storage and deployment. Durable design is suitable for longer term use applications. Usually the most affordable style of boom.
Cons: Lower stability and less buoyant than other booms. Externally attached floats can be more difficult to clean than flat foam chamber designs.
Other Kinds of Booms
Absorbent boom
As the name suggests, absorbent booms soak up—as well as confine—spills. They have a mesh tube exterior that is filled with synthetic sorbent material. Sorbent booms come in various lengths and diameters. They can be clipped together to create required lengths.
Different colors differentiate use with chemical (yellow), water (gray) or oil spills (white). Because they float on water, oil absorbent booms can be used in conjunction with conventional booms.
Trash and debris boom
Oil is not the only hazardous material that can pollute water ways. Trash and organic debris, like plant matter, can also be harmful. Containment booms can also be used to trap these materials, for removal by clean up response crews. Debris boom designs and water applications follow the oil boom features we outline above.
Conclusion
Booms are useful tools for preventing oil slicks spreading on the surface of the water. When used correctly, they help protect coastlines and marine ecosystems from the harmful effects of oil pollution.
There are many containment booms on the market for dealing with oil spills. Each design has advantages and disadvantages, from its cost to water conditions suitability. Knowing the differences is important so that you can choose the right boom type for emergency spill response.
If you’re looking for more advice on booms or other spill clean up supplies, contact us today. We have years of experience with emergency spill equipment and are happy to help.
Frequently asked questions
- What are booms for oil spills?
- How do oil containment booms work?
- What are the disadvantages of booms for oil spills?
- What is the difference between a boom and a berm?