Buyer's Guide:
The Questions to Consider Before Purchase

Helicopters are vital transport vehicles for oil rigs and ships. While weather conditions offshore are often harsh, restricting traffic more than absolutely necessary is in no-one's interest. Therefore, helicopter landing decks must be equipped for high friction and safe walking.

There are a few vital questions that should be carefully considered by everyone charged with a responsibility to select and purchase helideck safety nettings.

1. What is essential in selecting the material?

In general, all nettings used offshore should be ultra durable andresistant to weather conditions including ultraviolet radiation.

In landing nets, the ideal material provides high friction especially when moist and does not deform or distort regardless of weather. Low profile material without high knots increases safety and convenience of walking and enables the use of wheeled carriages.

In perimeter safety nets, the ideal structure is completely balanced and does not have knots, joiners or extra framing that most often are the weakest links. In addition, the material should produce a hammock effect and recover to its original form after tension.

2. Why is durability so important?

The highest possible durability is essential to ensure lowest total cost of ownership, as offshore installation costs often exceed theprice of the nettings.

In fact, from financial point of view, traditional abrasion-prone materials should not be accepted even for free.

In addition, worn-out or deformed materials obviously pose seriousrisks to safety.

3. What should be known of installation and maintenance?

Installation is crucially important, especially offshore, as the process is typically more expensive than nettings themselves. The installation method should be fail-safe, with crystal clear instructions.

In landing nets, the nets should include robust tension straps andratchets that ensure balanced tightness and invariable shape. For maintenance such as periodical cleaning of the helideck from guano, lightweight structure is ideal.

In perimeter safety nets, the ideal installation method does not require extra joiners or framing which most would most often be the weakest links. The safest and most balanced way is to attach the net directly to existing helideck frames, using the same material.

4. Why is fulfilling standards not enough?

Existing standards state minimum requirements. When it comes to safety, the responsible planning method is not to fulfil standards but to respond to real-life worst case scenarios.

When looking at standards' requirements, it is important to consider the entire life cycle of the nettings in harsh offshore conditions. Nettings that barely fulfil standards at the time of purchase will most probably not do so after 1-2 years.

Therefore, any new material and structure should exceed the standards' requirements in high multiples.

5. What should be known of testing?

When selecting landing nets or perimeter safety nets, historical data of real-life performance is by far the best predictor of expected lifetime. The longer the experience of any particular material and design, the more exact data the vendor has on the durability.

However, due to the harsh conditions offshore, safety equipment simply cannot be installed and forgotten. Periodical testing of all safety gear is crucial to measure their current strength and ensure theycontinue to provide the required level of safety.

Traditional testing method for perimeter safety nets has been to throw sandbags in the net and see if the net holds. The method is problematic in many ways. The test only tells if the net holds the load or not; the results do not tell how much the net holds.

As traditional materials will not recover in full, there is no wayto foresee when the nets should be replaced. At worst, the next tensionmay already be enough to break the net or its joiners.

The most reliable testing is done in a laboratory. However, removing nets and sending them for testing is costly and impractical. A novel method for testing is to include extra straps in the nettings, oneof which can be detached in regular intervals and sent to labs.

The results of the lab test tell the exact current strength of thematerial. Compared with long-term field testing data on the average pace of deterioration, it is possible to calculate a reliable estimate on the net's remaining lifetime.