Static electricity is everywhere so it may not seem like that big of a deal unless you’re surrounded by explosive chemicals. Even then drivers and other workers may become complacent and believe they don’t need to take the time to make sure their vehicle is properly grounded or bonded. But that is very dangerous and very wrong! Don’t let your drivers skip this life-saving step. Just one tiny spark is all it takes to create a huge disaster that can damage property, start fires and severely injure or kill workers.
Admittedly, there’s no way to totally eliminate static electricity. In a work setting, the most common static generators are processes that involve transloading flammable liquids:
• Filling Operations – Filling a tank or other container creates turbulence, and that can cause static electricity. Eliminate splash filling and free-fall of flammable liquids by lowering fill velocities, providing diverters so the liquid goes down the side of the grounded vessel, or fill from the bottom whenever possible.
• Filtration – Electrostatic charges can build up quickly when filters are being used so they should be installed far enough upstream from the discharge points so the liquid relaxes in time to dissipate the static.
• Piping Systems – The proper size pipe keeps chemical velocity low. Recommended maximum velocity is 15 feet per second. This will help keep accumulated static at a low level.
• Dispersing Liquids – Poorly conductive liquids can accumulate a charge that may trigger sparking in the vapor space. To remedy this, the conductivity of the liquid should be raised above 2000 conductivity units (C.U.) (2 x 10-5micromho/cm) before the particulates are added.
• Flash Point – All operators should know a liquid’s flash point, vapor pressure and temperature at all times throughout the process. Vapor levels will be higher in the air around a container during the summer when temperatures are higher.
• Venting – Containers must be vented so a vacuum does not form inside.
• Internal Pressure – Pressure relief valves keep pressure from building up inside and bursting a container.
Static sparking can’t take place between connected objects with the same potential. That’s why it’s so important for operators to ensure that their equipment is properly bonded and grounded. Bonding connects pieces of conductive equipment together to keep them at the same potential while grounding is a form of bonding that connects conductive equipment to the earth to prevent sparking.
There are two basic types of connections: permanent and temporary. So how do your workers know when they are properly bonded and grounded?
Your company can ensure maximum levels of safe, positive grounding for tank trucks during flammable transfer operations with a ground monitoring system specifically designed for tank trucks with rubber tires. Safety is the main issue here since systems:
• Only allow product transfer when the tank truck is grounded.
• Automatically confirm positive static ground connection.
• Continuously monitor clamp and ground connection during transfer.
Proper installation and testing of bonding and grounding equipment is of the utmost importance. Also, there should be an inspection and maintenance program set up to consistently ensure the continuity and adequacy of the system.
Prevent static-ignited fires and explosions with a static ground indicator and interlock system. Whenever flammable liquids or powders are transferred, or wherever there is a risk of conductive equipment becoming isolated from ground in hazardous locations, effective grounding and bonding is necessary to ensure safe dissipation of static electricity. This will help prevent fires and explosions.
These systems provide verification of static ground (earth) connections on industrial equipment including: drums, containers, railcars, and other conductive equipment.
Using multiple layers of protection is really the best way to ensure safety. Verifying bonding and grounding with visual, electronic and audio alarms, keeps workers, their jobsite and surrounding property safe. Contact Carbis today to find out how our bonding and grounding verification systems will keep your company safer during transloading operations that involve flammable chemicals.