Imagine yourself on top of a skyscraper in Sydney, looking down at a very narrow path from a great height. The wind is roaring. Suddenly, in the twinkle of an eye, what was just a topic in a safety presentation before, becomes very real, with real consequences. Selecting the best safety netting for your project should not be just a matter of ticking boxes from a generic checklist; rather, it is ensuring that your colleagues will still be able to see their family members after work. In our field of work, gravity leaves no room for second takes. If your safety measures are defective, besides attracting heavy WorkSafe fines, you will also be endangering human lives.
Match the Net to Your Hazard
So, how do you avoid a costly trial-and-error nightmare? You match the net to the hazard. It sounds simple, but you’d be surprised how often people get it wrong. Let’s clear up a major misconception: personnel fall arrest nets and debris screens are chalk and cheese.
- Personnel Fall Arrest Nets: Designed to withstand heavy hits, these giants are certified to have a minimum breaking strength of 5,000 lbs (approx. 22.2 kN) per mesh and can still pass an extremely tough 400-pound drop test. These are the ones to go for when standard guardrails are just not going to work.
- Debris Containment Nets: They are mainly meant for catching dropped tools, loose materials, and other site waste. They feature a denser mesh to hold small items, but the breaking strength is quite a bit lower, in the range of fifty to one hundred pounds.
Write this on the shed wall: you can never use a debris net to protect your personnel. Simple as that.
Polyethylene, Polypropylene, or Nylon?
Now, let’s talk about materials, because the fierce Aussie sun will absolutely shred cheap gear. You basically have three options:
- Polyethylene (PE): This is hands down the best material for outdoor durability. It is very resistant to UV radiation, doesn’t take in water, and maintains its flexibility year after year in the outdoor environment. Because of this, if you are thinking about a commercial build for the long run, this is the material you should go for.
- Polypropylene (PP): It is a lightweight material and quick costs or simplicity accountants’ smiles. Indirectly, the downside is that PP is very susceptible to sun damage and, because of this, PP without any kind of treatment only makes sense for short-term use (up to 6 months).
- Nylon (Polyamide): The heavyweight for strength and stretchiness, but it is still a real water-loving sponge. Besides that, it is very UV-ray sensitive. You should, that means, probably reserve nylon mainly for temporary protection at indoor sites or dry and very sheltered places where fall protection is required.
Height, Scale, and Rigging Specs
But material is only half the story; scale changes everything. In tall skyscrapers, wind at high altitudes can make the scaffolding behave like a huge sail. So, you need to use wind-reduction mesh that lowers the wind speed by as much as 60%. Mesh density must be balanced with the wind load that the structural engineer calculates.
For rigging, it is a fact that “close enough” is not good enough. “She’ll be right” is a risky way of thinking in this matter. Accuracy is the key:
- Mind the Gaps: Aim for zero gaps. Regulations allow exceptional gaps of up to 100mm, but absolutely never go beyond 225mm.
- The 10% Sag Rule: Determine the amount of sag for your nets by taking 10% of the net span as a reference. If you make them too tight, they’ll behave like a firm trampoline; too loose and one way or another someone will be on the ground.
- Size Up: Net borders pull inward when hung. Always order your nets oversized by at least 10% on all sides.
- Overlap properly: Don’t ever just join net edges without a seam. Overlap them by at least 15cm and fixing them with UV-suitable ties every 30 to 50cm is recommended, or alternatively an overlap of at least 2m can be used without lacing.
Maintenance and the Five C’s
Finally, establish a strict maintenance routine for construction safety nets on your site. This relies on the five C’s: compliance, certification, capacity, craftsmanship, and care.
- Daily Visual Checks: Riggers must check daily for broken strands or loose ties.
- Weekly Formal Inspections: Perform weekly checks to verify tension, gap limits, and anchor points.
- Annual UV Strength Testing: Safety nets typically expire twelve months from their manufacture date. Send the attached test mesh strips to a certified lab annually to monitor UV degradation and keep your certification valid.
- The 2-Repair Limit: A single net must not exceed two significant repairs during its service life before it must be retired immediately.
- The Three D’s of Storage: The best practice for cleaning is using mild detergents only, allowing them to air-dry, and keeping them Dry, Dark, and Detached from the floor to avoid rodent damage.
Conclusion:
Working out your commercial netting strategy ahead of time will not only save you quite a bit of money, but also keep your team safe and avoid delays on the project that will be very costly.
