Friday, April 10, 2009
I think that machine guarding is probably the most overlooked deficiency in industry. The reason being that the guards get in the way, slow down production, and the mindset that there was never a guard there. This is a form of complacency. Complacency seems to be the most common factor in the majority of accidents I have investigated.
OSHA requires all machines to be guarded. An employer must guard any machine without a guard, even if it was purchased without guards. This is especially relevant in manufacturing. From my work in the printing industry it was not uncommon to see a printing press, die cutter, etc. that is about 100 years old. This is also common in the woodworking industry too.
In many of these machines there are only 5 things that can go wrong and they are all replaceable wear parts. They are bushings/bearings, drive belts, cutters (the working tool), feeders, and the drive motors. (Some may argue that motors are not wear parts, but they are designed to be rebuilt.) Unlike many of the newer machines that rely on electronics, the older machines will last forever.
The most common unguarded machines I see are table saws and drill presses. As for the drill presses, I am not fully convinced that a guard is practical. I think that is because I have not seen a really good design for a drill press guard. Sears offers a pretty good guard retail! The Sears Craftsman guard is pictured above.
I have also seen 1 or 2 guards that were fabricated at shops that were designed pretty good also. The one drawback is that they limit the functionality of the drill press. I have an open mind and I am always looking to advance safety, so I continue to look for a good drill press guard.
For table saws, there is an amazing product called Saw Stop. If you touch the blade, it stops the saw blade before it can cut you. You can watch the video here: http://www.sawstop.com/