CONTROL OF HAZARDOUS ENERGY

1. CONTROL OF HAZARDOUS ENERGY

2. Types of Energy To Be Controlled • Kinetic – Energy of motion • Potential – Energy of position • Electrical – From generated electricity, battery or static source • Thermal – result of mechanical work, radiation, chemical reaction or electrical resistance

3. 7 Basic Lockout Steps • Prepare for Shutdown • Shut Down • Isolate • Apply Locks • Verify Isolation • Control Stored Energy • Prepare for Startup

4. What is Isolation? • Meaning – Prevention of the normal flow of energy. • Blocking in the case of gravitational energy • Disconnection in the case of electrical energy. • Ether blocking or disconnection in the case of the flow of fluid through a pipe.

5. What Does “Apply Locks” Include? • Apply Locks = Securing the Point of Control • Preventing unauthorized persons from reactivating the flow of energy. • Use of locks, tags or posting of qualified person(s).

6. What Does “Control Stored Energy” Mean? • Cause Energy To Be Reduced to Levels Tolerable by Humans.

7. Mechanical Motion • Can be linear translation or rotation • Allow motion to stop before work. • Can be turned off

8. Potential Energy • Potential Energy – Pressures, springs, and gravity. • Can be controlled, but can not be turned off

9. Electrical Energy • Electrical power can be turned off • Static Electricity cannot be turned off, but can be dissipated

10. Thermal Energy • High or low temperature • Result of: • Mechanical work • Radiation • Chemical reaction • Electrical Resistance • Can’t be turned off – must be controlled or dissipated

11. Chemical Reaction • Take heat in or give off heat • Controlled by: • Elimination, dissipation or control of chemically-reactive materials • Control reaction so energy release doesn’t harm humans.

12. Example –Control Potential Energy by Removing Spring From Car • Control gravity by blocking the car • Control spring energy by blocking or dissipation of energy.

13. Example – Mixing Drum Rotating Blades Repair • Switch off electrical source • Lock out and/or disconnect mechanical linkages • Tag switch (and mechanical linkages?)

14. Forms of Hazardous Potential Energy – As You Come Up With Examples Of These At Your Site, Raise Your Hand And Let’s Discuss How You Control Each One! • Hydraulic or pneumatic pressure • Vacuum systems • Compressed or extended springs • Gravity energy • Energy of motion such as a flywheel • Stored electrical energy – Battery, Capacitor • Thermal Energy due to residual heat or low temperatures • Residual chemicals in pipe which may cause thermal or pressure buildup.

15. Controlling Hazardous Energy Sources by De-energizing • Thorough Inspection and Listing Of All Potentially Hazardous Energy Sources • Include adjacent equipment

16. Controlling Hazardous Energy Sources by De-energizing • Stored or residual energy that constitutes a personnel hazard shall be isolated, blocked or dissipated. • Isolate, block or dissipate at points of control that cannot, with reasonable effort, be overridden or by-passed • Isolation or blocking is adequate when unplanned event would not reactivate the flow of energy

17. Applying Locks or Securing The Point of Control • Use of physical means such that re-energizing requires special equipment routinely available only to the person who applied the control or. • Post warning at the point(s) of control saying why controlled, date, person(s) responsible for control and for work to be done. Limit access to control point(s) or • Post Qualified personnel at the point of control with specific responsibility of protecting against unauthorized actuation (used primarily for short duration work..

18. Verify Effectiveness of Controls • Ensure that all hazardous energy has been isolated, blocked or dissipated in areas where personnel will perform required tasks. • Verification may need to be continuous if there is a potential for re-accumulation of energy.

19. Controlling Hazards With Energy Present • Identify hazardous energy sources including residual energy sources • Document procedures and assign responsibility and accountability for controlling personnel hazards • Qualify personnel who perform maintenance by education, experience and/or training and certification

20. Example - Controlling Mechanical Motion • Remove segments of operating mechanical linkages such as dismantling push rods, removing belts, removing flywheels. • Secure Point of Control • Tag linkages and place in locked cabinet • Attach warning tags where linkages removed & restrict access • Post person to protect against unauthorized reinstallation of linkages

21. Example - Controlling Mechanical Motion • Use blocking devices • Secure point of control by: • Chain and lock or use metal pins driven or welded in place • Attach warning tags and restrict access • Post person(s) to protect against unauthorized removal of blocking devices

22. Example - Controlling Mechanical Motion • Remove Power or energy by disconnecting main electrical source or closing hydraulic or pneumatic valves, bleed. • Padlock in the “off” position (check for alternate sources of power)

23. Example - Controlling Mechanical Motion • Close hydraulic or pneumatic valves, bleed. • Disconnect pneumatic and hydraulic lines and tag or attach warning tags at control points and restrict access to trained personnel or post a person • Check for residual pneumatic and hydraulic energy.

24. Example - Controlling Electrical Energy • Place the main electrical disconnect switch in the “off” position • Secure by padlock, clip and padlock or bar and padlock (check for alternate sources of power and programmed controllers) or • Attach warning tag and restrict access to trained personnel or • Post a person

25. Example - Control of Electrical Energy • Remove segments of electrical circuit, such as printed circuit modules. • Tag module and lock in cabinet away from control center; Tag control center door or • Attach a warning tag at the module location and restrict access or • Post person at control center

26. Example - Control of Thermal Energy (Steam) • Close valves and maintain an open bleed. • Chain and padlock valve or use blind flanges or slip blinds or • Attach warning tags to the valves and restrict access or • Station person at valve locations

27. Example - Control of Pressure Energy • Close valves and maintain open vent to relieve • Secure, block, blind flange, slip blind, or valve with locking device or • Attach warning tags and restrict access • Station a person at the valves

28. Example - Control of Gravity Energy • Block in place using metal or wood blocks under the mechanism or pin the linkages in position where gravity won’t cause the mechanism to fall. • Energy could be dissipated by lowering to floor or other secure surface or • Secure, block or pin with a locking device or • Attach warning tags to blocks, linkages and pins and restrict access or • Station a person to restrict access

29. Example - Controlling Spring Energy • Block in safe position by pinning or clamping • Dissipate energy by release or dismantling of the mechanism or • Secure pin or clamp in place with locking device or • Attach warning tags to pins and clamps and restrict access or • Station person at control point to protect against pin or clamp removal