Linear Energy Restraint
Linear energy restraint is an engineered system that limits, absorbs, or redirects kinetic energy from linear motion of machine components, hoses, pipes, tools, or workers to prevent injurious forces. It combines restraint functions with energy design criteria to comply with WorkSafeBC, OSHA, CSA, and ANSI standards for hazardous energy control.
On a shop floor, linear energy restraint applies to hose whip checks on pressurized lines, guards sized with energy absorption formulas to contain ejected parts, fall restraint systems limiting worker travel, and vehicle restraints preventing unplanned movement. These systems are designed using dynamic impact criteria rather than static loads alone, with documentation of ultimate capacities and energy ratings. WorkSafeBC requires engineered restraint systems for flow piping and effective means of restraint where unplanned motion could endanger workers, integrating with lockout procedures to control residual energy.
How is hazardous energy related to linear energy restraint?
Hazardous energy includes mechanical, hydraulic, pneumatic, and other sources that can injure workers. Linear energy restraint controls mechanical manifestations where motion is linear, such as thrust in piping or ejected material. While lockout removes energy, linear energy restraint manages residual or incident energy when systems remain energized or components fail.
What engineering calculations underpin linear energy restraint of guards?
WorkSafeBC uses energy absorption formulas: Ev = 0.152W (SI) or Ev = 6W (imperial), where Ev is ultimate energy absorbed at impact. Engineers compute kinetic energy of ejected objects (Ek = 0.5mv^2) and ensure guards absorb at least that energy, checking yield, welds, and deformation limits per CSA Z432.
How do we verify a hose/pipe restraint system is adequately engineered?
Identify operating parameters (pressure, fluid, size), calculate thrust forces and disconnection motion, select a restraint system with components rated above maximum dynamic load, and confirm an engineered design from the manufacturer or a professional engineer. Document design ratings and integrate inspection tasks into SafeDesk.