Issue link: https://www.e-digitaleditions.com/i/964311
22 POWDER COATING, April 2018 Maintaining a safe blast booth In the April 2013 issue of Powder Coating, I wrote an article on sand blasting (abrasive blasting) as pre- treatment for powder coating. I provid- ed an overview of the process and the impressive results that can be achieved when blasting is used with a two-coat powder coating system. (Editor's note: You can access this article for free by vis- iting www.pcoating.com and searching the Article Archive by author.) To continue the discussion, the focus of this article is on maintaining a safe oper- ating blast booth in your production facility. While not an exhaustive list, nor a replacement for the guidelines provid- ed by your equipment supplier, the intent of this article is to provide food for thought based on the experiences that we have had at Aegis and some insight into factors that may not be immediately apparent. The areas covered in this article will be: • Operator safety • Equipment maintenance • Safety check schedule Safe operator If you run abrasive blasting in your plant, you likely have safety guidelines that your employees have to fol- low when operating the blast booth. Your guidelines likely address the pro- tective equipment that an operator must wear, the training that they must have undergone before operating the blast booth, and safety checks that must be done. At the very least, your operators should be wearing positively pressurized hel- mets designed specifically for abrasive blasting, as shown in Photo 1. This unit likely comes with a belt that holds the air line and protective bib close to the operator's body. In addition to the hel- met, your operators should also be using hearing protection, protective footwear and gloves, and coveralls. While blast equipment suppliers sell purpose- designed blast coveralls, we have some operators that prefer to wear cotton cov- eralls over their work clothes. As for blast gloves, welding gloves seem to be the favored style of glove for operators. If you have the above covered, the next step is to drill into your operators the proper use of the deadman switch. See Photos 2a and 2b. (A quick aside: For those who are considering adding blast- ing to their operation, the deadman switch completes either an electric or pneumatic circuit which activates the air that pressurizes the blast pot, thus beginning the blasting process.) It seems to be an immutable law — if an operator can make their life easier, they will, albeit at their own expense in cer- tain situations. I had one new blaster proudly explain to me that they found a way to operate the paddle deadman with ease by using a zap-strap to secure the deadman paddle down, making it easier for them to handle the blast hose. This is not a good idea. The purpose of the deadman is to quickly cease the operation of the blast system in case the operator loses control of the blast hose. By securing it with a zap strap (or banding wire, tape, rope, etc.), the safety feature is eliminated. I once heard from a supplier of an opera- tor who used this method of productiv- ity improvement at his own expense. He passed out in the blast booth, and when he came to he realized that the blast hose was still blasting as it ripped through the knee of his coveralls. Chris McKinnon Aegis Industrial Finishing Coater's Corner Coater's Corner Photo 1 Photo 2a Photo 2b