There are no Brazilian norms that determine the maximum weight of the worker at height. The ABNT NBR norms (NBR 14626, NBR14627, NBR14628, NBR14629, NBR15834, NBR 15835, NBR15836 and NBR15837) are not norms about working at height, but about product manufacturing. These norms do not limit the worker’s weight. They only establish test methods for products.
The test dummie with 100 kg is standardized and is the same one used all over the world. The fact that it is the same for all tests creates an evaluation standard among the harnesses offered in the world market.
By simulating the crash with a factor of 2 and the required “zero” defect result, one can conclude that the belt can certainly withstand the weight of an individual over 100 kg. The calculation based on Torricelli’s formula shows us that a 100 kg body falling from a height of 4 m attached by the test rope results in approximately 800 kgf. Testing lanyards with energy absorbers under the same conditions should result in no more than 600 kgf.
For the safety of any worker at height there is a need to establish a standard for “the whole set” of equipment. That is, the anchorage points and structure that should withstand the impact of a fall – the rope, connectors, etc.
What good is a strong harness if the rest is not dimensioned accordingly?
There are several procedures and recommendations for a safe work that can prevent and minimize the impact of a fall, such as never anchoring your lanyard and fall arrest device below the waist.
Another factor that must be taken into account is that fall arrest lanyards must have an energy absorber to reduce the impact caused to the worker in case of a fall. The size of the lanyard should be as small as possible, meeting only the mobilization needs and, consequently, decreasing the size of the fall. This means that the impact resulting from the fall will be reduced, compared to the impact of the factor-2 fall suffered by the dummie during the test. In addition, risk awareness training and proper techniques for using the equipment, as well as strong and safe anchorage points are fundamental.
It is up to the Safety Engineer and Technician to determine which PPE and procedures should be used for a particular job. It is also necessary to take into consideration the other issues involved in working at height, such as the fall factor and the occupational medicine clearance of the individual who will be using the equipment.
We conclude that Hércules fall protection equipment can be used by people weighing over 100 kilos, and we recommend that the 136 kilo limit be respected, taking into consideration the weight of the worker and the weight of their equipment.
Did you know that Hércules has a highly qualified technical team available to understand your needs and present the most adequate solution for your operation? Contact one of our specialists.