Recently, OSHA ruled on new limits regarding worker exposure to crystalline silica dust. This has caused some concerns across the industry where silica reduction measures have been implemented to minimize its health risk effects. The argument is that these new limits will do little to further improvement in worker health and safety. But, if you have been considering ways to mitigate silica dust in your process or if the new ruling simply forces you to prioritize this endeavor, it is hard to argue that keeping you or your employees away from the hazard in the first place is a good start.
The new ruling reaches across many industries where silica is used in everyday operations such as in:
And since one the key provisions of the ruling is to limit worker access to high exposure areas, the implementation of level monitoring devices can dramatically reduce direct exposure and dust dispersion in the surrounding areas making it safer for everyone.
Challenges from the past
Your experience with level instruments in extremely dusty environments may remind you that the material level in such environment is not easily monitored. This may be the very reason why somebody has to go up the silo, open the hatch and take a manual measurement – allowing the dust to simply escape and coat everything and everyone. A few years back, I would have agreed with this. Silica sand or similar granular materials create a lot of dust and their inherent steep angle of repose can cause unwanted signal skipping, thereby challenging most level instruments. However, now there is a viable measurement solution. A huge game changer was introduced to the industry: a radar level transmitter that operates at 78 GHz.
So, what can a radar transmitter operating at 78GHz do and how did it improve the industry?
The thing is frequency matters because as the frequency gets higher, the wavelength gets smaller. What this means is that the transmitted signal of a 78 GHz radar transmitter can penetrate dust more easily than traditional radar transmitters operating around 25 GHz. Great dust penetration and excellent signal reflection from sand like products has become a plug and work solution with 78 GHz radar transmitters. This is true even for silos exceeding 100 ft. in height. Furthermore, 78 GHz yields only a 4 degree beam signal and, more importantly, without the need of a large horn antenna. This offers a new level of flexibility since these radar transmitters can be mounted virtually on any process connection on top of a silo, thus saving on retrofitting costs.
Implementing a level monitoring solution not only increases the worker’s safety, but inventory management becomes a reality since you will soon trust that the indicated level is consistent and dependable.
Although OSHA’S ruling spells out how to reduce silica dust exposure, the ruling offers flexibility to the industry as long as the industry’s own measures achieve the same end, which is a safer environment for the employees.
While some in the affected industries are hoping Congress will enact legislation to prevent the ruling from taking effect, it is also speculated that the ruling will stand and compliance will begin as proposed – starting in June 2016 for some industries.
I believe that even if the ruling is modified, the wheels are in motion and some kind silica dust reduction measures will take place. So, if you wait till the dust settles and then find yourself in a time crunch to come up with a solution, don’t reinvent the wheel, go with what works.