# Blasting Zone **URL:** \ **Category:** Factual Questions\ **Created:** [June 17, 2017, 1:37am UTC](https://boards.straightdope.com/t/blasting-zone/789153 "2017-06-17T01:37:31Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Procrustus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/procrustus/32/2994_2.png) [@Procrustus](https://boards.straightdope.com/u/Procrustus)\ **Post date:** [June 17, 2017, 1:37am UTC](https://boards.straightdope.com/t/blasting-zone/789153/1 "2017-06-17T01:37:31Z")
So, I was driving around rural Kentucky this morning and saw a sign I hadn’t seen in years. > [@](#): > > Blasting Zone > Turn off cellular phones and two-way radios I assume approximately zero percent of drivers followed this directive. My question, is this a danger to the people working there? If so, how much of a danger? I would think if we were exploading dynamite with our phones, the signs should be a little more _ **insistent** _. ---
**Author:** ![Terry\_Kennedy](https://avatars.discourse-cdn.com/v4/letter/t/c57346/32.png) [@Terry\_Kennedy](https://boards.straightdope.com/u/Terry_Kennedy)\ **Post date:** [June 17, 2017, 2:30am UTC](https://boards.straightdope.com/t/blasting-zone/789153/2 "2017-06-17T02:30:15Z")
> [@Procrustus](#): > > My question, is this a danger to the people working there? If so, how much of a danger? I would think if we were exploading dynamite with our phones, the signs should be a little more _ **insistent** _. I would have thought that everyone had moved to shock tube for both safety and improved performance, but a search for “blasting wire” still shows a large number of suppliers, so it must still be used. Aside from the problems with long runs of blasting wire acting as an antenna and causing unwanted detonations, all of the connections need to be electrically connected together and tested. With shock tube, you just clip / tape / etc. the lengths together and you’re good to go. You also get a choice of delays, which turns the detonation from one big “kaboom” into something more useful - either more complete disintegration of what you’re trying to get rid of, or a slicing action if you want to break off large chunks of something intact. To answer your question, it does happen - for example, see [Reports of Premature Initiation of Electric Detonators by Radio Frequency Energy](http://ermanagers.com/wp-content/uploads/2015/02/RF-incident-reports.pdf) (PDF). [SAFETY GUIDE FOR THE PREVENTION OF RADIO FREQUENCY RADIATION HAZARDS IN THE USE OF COMMERCIAL ELECTRIC DETONATORS (BLASTING CAPS)](http://energetixsolutions.com/downloads/IMESLP20SafetyGuideforthePreventionofRadioFrequency.pdf) (PDF, sorry for the all-caps) has tables for various frequencies, distances from the site, and transmission power levels. ---
**Author:** ![Procrustus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/procrustus/32/2994_2.png) [@Procrustus](https://boards.straightdope.com/u/Procrustus)\ **Post date:** [June 20, 2017, 4:33pm UTC](https://boards.straightdope.com/t/blasting-zone/789153/3 "2017-06-20T16:33:07Z")
Thank you for your response. (Shortest thread ever). The PDF’s were informative and seem to suggest the danger of using your cell phone in your car while driving by a blast zone is non-existent. ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [June 20, 2017, 6:15pm UTC](https://boards.straightdope.com/t/blasting-zone/789153/4 "2017-06-20T18:15:02Z")
I knew a fellow who worked in the safety department of a mine. He said they tested wired blasting caps (as opposed to shock tube or fuse) and even hanging them over the antenna of an industrial walkie talkie didn’t set them off. (Of course, they tried with less risky tests before doing something right in front of themselves…) So the risk is there, and I imagine an extremely long wire or a coil of it, could possibly pick up a induced signal.