The gleaming, intricate parts emerge from 200 lb. slabs of aluminum alloy that have recently been cut by a screaming 50 hp saw from even larger sheets of the stuff. Chips are flying and coolant is spraying from high speed tool bits controlled by carefully written CNC (Computer Numerically Controlled) programs. Attentive, highly skilled milling machine operators watch as first the part moves and then the tool bit is positioned. They are making components for the next generation of space exploration machines.

Seemingly delicate suspension system parts for the new lunar rover are arranged as if on display on the carts marked "Work In Progress" in front of their machines. There is an air of purpose and mission in this huge building whose primary charge is to support the NASA astronaut training facility and research arm at the Johnson Space Center, Houston, Texas. There is also ample evidence of a strong commitment to worker safety, even on a small scale. Right next to the rover part, as it sits in front of the machine that just produced it, is a neatly lettered red and white sign that reads: "CAUTION - SHARP EDGES" warning anyone of the risk of laceration should they dare to handle this freshly minted piece of the future.

Jacobs-Sverdrup, the firm that runs this shop and many others for NASA, recently chose my company, Lovegreen Risk Management, to do two things. First, it was my privilege to assess the machine guarding and control hazards at this shop and the adjacent wood and model shop. My survey last year included over 100 machines. Second, we were chosen to propose, design, fabricate and install solutions to the machine safety and regulatory compliance issues I found and recorded. We recently returned from a 2-week project wherein we fulfilled our proposals. The way in which we helped solve their problems is characteristic of our work.

Here is an example of our approach. Among other machines, this shop contained 10 Hurco CNC Vertical Mills. These mills are characterized by having a large table, sometimes up to 8 feet long and about 4 feet wide on which the work piece is held by clamps. The CNC system drives this work-holding table in 2 directions, left/right and in/out. Above the table a rotating tool bit is suspended that can go up and down. Adjacent to the tool bit is a tool changer that holds a large number of different bits. These bits are automatically substituted under the direction of the CNC system. Once the work piece is manually clamped in place and the tool bit is zeroed by the operator, the CNC program guides the motions of the machine. While the bit is engaging the work piece, multiple streams of water-based coolant bathe the point of operation, cooling the tool bit and carrying away some of the chips. Everything that is not "the part" becomes an airborne chip that flies away from the point of operation in a spray of coolant.

The manufacturer of these machines provided a 3-sided enclosure around the work holding table to help contain chips and coolant. Unfortunately, like so many other manufacturer-supplied machine shields, it is inadequate. Once I characterized this hazard, my task was to help design a supplementary shield system that would: 1. Provide a user-adjustable shield intended to comply with basic OSHA machine safety standards. 2. Help control and deflect broken tool bits and loose inserts if these hazards should occur. 3. Provide a user-adjustable shield intended to comply with basic OSHA machine safety standards.

This shield system should have the following characteristics: It must be compatible with and supplementary to the existing OEM machine enclosure. It must not require significant modification of the machine or require significant downtime to install. It must be user adjustable through a wide variety of configurations and be capable of stopping or deflecting chips and coolant normally produced by the machining process. It must be made of parts and materials that are compatible with the process and which are reasonably priced and be capable of being fabricated and installed quickly in the field with standard hand tools

We chose to design, fabricate and install a rather low-tech shield set for machines that are turning out some of the world's most high-tech parts. We provided each of the ten Hurco mills with a set of four shields. Each shield is fabricated from ?" thick polycarbonate sheet cut to fit the particular side of the steel OEM mill enclosure or "tub". The shield is fitted with two simple handles near its upper edge that the operator may use to position the shield. Below the handles, near the lower edge of the shield, two powerful ring magnets are fitted in chromed steel cups. These magnets secure the shield to the inside vertical surface of the tub in almost any position the operator may choose. To position the shield, the operator pushes away and breaks the magnet's hold. Once he chooses a new location, he allows the magnets to regain their hold. We call this the LRM MagnaShield.

I am pleased to report that the MagnaShield gained almost immediate acceptance and praise from the operator's on whose machines it was installed. Management staff saw its utility immediately and are including it in their Safety Action Plans for this machine type.

Fifty years ago, I stood in a dark North Dakota farm-yard and desperately scanned the sky, trying to see Sputnik. Later, I dreamed of working for NASA and the US space program. While I realize that I will never be an astronaut, I feel I have contributed in a small way to the effort to explore the stars by helping to protect those who support the explorers. Safety has its own rewards.

Dave Volker

Safety Consultant LRM, LLC

Dave Volker is a safety consultant with Lovegreen Risk Management. He may be reached at dvolker@lovegreen.com. Visit the Lovegreen website at http://www.lovegreen.com