- HSSE WORLD

Safety nets are quickly becoming the preferred method of fall prevention in construction. Learn what they are, and how to make sure your safety net passes the test.

When I got my first construction job after moving to a big city, I was a bit nervous. I wasn’t used to working at heights. I had worked on the rooftops of a few houses, but working on a high rise building was a whole new ballgame. On my first day, I lost my balance near the edge and I was sure I was going to fall. Thankfully, I managed to catch myself, but it made me realize it could happen to anybody. That’s why I never take for granted the safety nets my company set up in case one of us isn’t as lucky as I was that day.

Safety Nets Are Growing in Popularity

When a worker is exposed to a potential fall from a height of six feet or greater vertically, the employer is required to do at least one of the following:

Install guardrails
Provide a personal fall arrest system
Set up safety nets

Among these options, safety nets are gaining in popularity. When installed properly, safety nets can reduce the distance of a fall from a high level, or prevent the fall altogether. They’re an attractive option for employers because they eliminate the need to provide each employee with their own individual fall protection equipment, which not only cuts back on equipment costs for larger teams but also means workers have to spend less time inspecting each individual item (for more on inspecting fall protection equipment, see How to Inspect Your Fall Harness When Working Alone).

Safety Net Regulations

As with any fall protection system, OSHA outlines regulatory specifications for the proper use of safety nets. Here’s what you need to know.

Placement

Safety nets must be installed as close as possible to the working surface, or the surface from which the fall may take place, but must not be further than 30 feet below in either case.

When safety nets are used on bridges, the potential fall must be unobstructed.

The safety net must extend outward from the outermost projection of the work surface in the following manner:

The vertical distance from the working level to the horizontal plane of the net will determine the minimum required horizontal distance of the outer edge of the net from the edge of the working surface
If the vertical distance is up to five feet, the maximum horizontal distance of the outer edge of the net from the working surface is eight feet
If the vertical distance is between five and ten feet, the maximum horizontal distance of the outer edge of the net from the working surface is ten feet
If the vertical distance is over ten feet, the maximum horizontal distance of the outer edge of the net from the working surface is 13 feet

Safety nets must be installed with enough clearance to prevent contact with any other surface or structure under them when subjected to an impact force equal to the weight used in the drop test.

Drop Testing

The drop test consists of a 400 lb. sandbag dropped from the highest height from which a potential fall might occur, and from no fewer than 42 inches above that level.

Safety nets must be drop-tested on the job site at the following times:

After installation and prior to first use
If the net is relocated
After a major repair
After six months, if the net is left in place

Certification

Once the safety net has been drop tested and has been shown that it is capable of absorbing an impact force equal to the weight used in the drop test, the net may be certified for use by the employer or other competent persons.

The certification means that the net is compliant with the regulations for impact absorption, as well as sufficient clearance.

The certification record must include:

Identification of the net to be used and the net installation
The date at which the net was demonstrated to be compliant with the impact force standards
Signature of the individual deeming the net compliant

The employer must keep the most recent certification available on the job site and readily available for inspection.

Inspections

Nets must also be inspected at regular intervals—at least once per week, and after any occurrence that might have affected the integrity of the system. Defective nets must never be used and should be tagged and repaired or removed from service. Nets should be inspected at least once a year for UV-related deterioration.

Other Considerations

Objects that have fallen into the net must be removed immediately.

The maximum mesh size must not exceed six inches by six inches. Mesh crossings must be secured in an effort to reduce the possible enlargement of the mesh opening. This must be no larger than six inches when measured from center to center.

Each safety net, or section of net, must be equipped with a border rope for webbing with a minimum breaking strength of 5,000 pounds.

Connections between nets must meet the same minimum requirements as any other net components and must not be spaced more than six inches apart.