Presentation on theme: "Safety Considerations. High voltage High current POWER SUPPLIES can cause burns or start fires even at low voltages MAINS VOLTAGE is potentially lethal."— Presentation transcript:
High voltage High current POWER SUPPLIES can cause burns or start fires even at low voltages MAINS VOLTAGE is potentially lethal Repairs HIGH POWERED TRANSMITTERS also have lethal voltages inside BATTERIES can also supply enough current to make wires red hot Rings and watches must be removed before dealing with high voltages and currents Repairs should only be undertaken by a suitably qualified technician quite small currents can kill! One hand should be kept in a pocket to avoid current passing through the chest >>
Mains plugs & earths A correctly wired plug THE MAINS EARTH is intended to protect you under fault conditions You are not expected to be able fit a plug until Switch off the mains supply before touching Accidents & Emergencies reproduced from the RSGB publication 'Foundation Licence Now!' A FUSE of the right rating fitted in a plug is a vital part of the protection system. PROTECTIVE MULTIPLE EARTHING (PME) to recognise when it is safely fitted with the correctly rated fuse installed. >> shock and could still be touching a live wire! they may have suffered an electric the Intermediate exam. It is useful to be able The casualty!
Antennas & feeders even if they are insulated! FEEDERS must be: ANTENNAS must be: Routed to avoid being trip hazards Fixed securely enough to survive gale force wind conditions Located where they can't be reached and won't be walked into Out of reach if unscreened to avoid RF BURNS Far enough away to avoid contact with overhead power lines WORKING AT HEIGHTS Erecting antennas must never be attempted alone Hard hats should be worn by people on the ground >> At least one adult should be in attendance preferably two One person should “foot” the ladder to prevent it slipping from the RSGB publication 'Amateur Radio Exam Secrets' The ladder should be placed at the correct angle from the RSGB publication 'Intermediate Licence Building on the Foundation' Never lean out when on a ladder! 4:1
Car batteries Are designed to supply very high currentssufficient to melt heavy gauge wires! Charging them causes the release of hydrogen which can be explosive in an enclosed space! They also contain a very corrosive acid spills and splashes can cause serious injury and damage! Headphones Wearing headphones carries risk: Long periods of high listening levels can in time result in permanent hearing loss When servicing equipment could lead to electric shock If you walk away with them on equipment could be dragged off the work surface >> Consider using the safer sealed batteries instead
Other hazards The shack can contain a number of other potential risks: Tools often have very sharp edges causing cuts Cables trailing onto and across the floor are trip hazards from the RSGB publication “Foundation Licence Now!” Soldering irons get very hot and can cause severe burns Most tools can cause injury when used incorrectly Cables running under carpets can become fire hazards Remember - most hazards can be avoided by thinking and planning ahead >>
Revision questions from the RSGB publication “Foundation Licence Now!” What colour is the neutral wire in a mains plug green/yellow, blue or brown? What's wrong here? Why must unscreened feeder be out of reach? RF burns are possible even if wires are insulated. The person footing the ladder could be in danger of serious head injury if something is dropped from the top of the ladder. Hard hat is essential! >> from the RSGB publication 'Amateur Radio Exam Secrets'