The Minor Servicing Exemption LOTO s Misunderstood Requirement

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The Minor Servicing Exemption LOTO s Misunderstood Requirement Carlos Gallegos Assistant Area Director - Response Team Aurora Area Office gallegos.carlos@dol.

1 The Minor Servicing Exemption LOTO s Misunderstood Requirement Carlos Gallegos Assistant Area Director - Response Team Aurora Area Office gallegos.carlos@dol.gov Goals Review LOTO application Define employee roles Review Acceptable Isolation Devices Compare Machine Guarding to LOTO Special Equipment/Circumstances Discuss the Minor Servicing Exception 1

Servicing Region V Top 10 Most Frequently Cited (Manufacturing) 348 350 300 250 200 168 156 153 133 127 150 100

2 Goals Review Machine Guarding When is Machine Guarding sufficient Related Standards E-Stops Performance and Control Reliability Safeguards Circuit Integration (relays + contactors) Examples of machine guarding in Minor Servicing Region V Top 10 Most Frequently Cited (Manufacturing) National Top 10 Most Frequently Cited (Manufacturing FY-16)

3 Presentation References 29 CFR The Control of Hazardous Energy (Lockout/Tagout) CPL The Control of Hazardous Energy Enforcement Policy and Inspection Procedures ANSI B American National Standard for Machines Performance Criteria for Safeguarding Definitions "Affected employee." An employee whose job requires him/her to operate or use a machine or equipment on which servicing or maintenance is being performed under lockout or tagout, or whose job requires him/her to work in an area in which such servicing or maintenance is being performed (b) 8 Definitions "Authorized employee." A person who locks out or tags out machines or equipment in order to perform servicing or maintenance on that machine or equipment. An affected employee becomes an authorized employee when that employee's duties include performing servicing or maintenance covered under this section (b) 3

Authorized Employee (CPL:Pg 1-4) Any employee who implements a lockout and/or tagout system procedural element on machines or equipment (for servicing and/or maintenance purposes) is considered an

4 Authorized Employee (CPL:Pg 1-4) Any employee who implements a lockout and/or tagout system procedural element on machines or equipment (for servicing and/or maintenance purposes) is considered an authorized employee: perform energy source isolation; implement lockout and/or tagout on machines or equipment; dissipate potential (stored) energy; verify energy isolation; implement actions to release LOTO; or test or position machines or equipment. Required Training Authorized employees Recognition of hazardous energy sources Type and magnitude of energy in the workplace Methods for energy isolation / control Affected employees Purpose and use of energy control procedures Other employees in work area Procedures related to restarting machines 11 Servicing and/or Maintenance (CPL:Pg 1-10) Workplace activities such as constructing, installing, setting up, adjusting, inspecting, modifying, and maintaining and/or servicing machines or equipment. These activities include lubrication, cleaning or un-jamming of machines or equipment and making adjustments or tool changes, where the employee may be exposed to the unexpected energization or start-up of the equipment or release of hazardous energy. 4

Energy Isolating Device (CPL:Pg 1-5) A mechanical device that

Push-buttons, selector switches, safety interlocks and other control

surface, which is done about once an hour.

5 Energy Isolating Device (CPL:Pg 1-5) A mechanical device that physically prevents the transmission or release of energy. Push-buttons, selector switches, safety interlocks and other control circuit type devices are NOT energy isolating devices. Alternative Effective Protection? Employee reaches into the die in a hydraulic press to clean die surface, which is done about once an hour. The press has a light curtain for protection. Assume this is minor servicing work. Is the employee considered authorized or affected? 14 Adequate device for energy isolation? 5

CPL 02-00-147; Pgs. 3-25 Thru 3-32 MINOR SERVICING EXCEPTION TO THE LOCKOUT/TAGOUT STANDARD Lockout/Tagout & Employee Protection (CPL:Pg.

147(a)(2)(ii)) Machine Guarding Must provide effective employee protection. Utilizing the cord and plug connected equipment or hot tap exemptions i.e., 1910.

6 CPL ; Pgs Thru 3-32 MINOR SERVICING EXCEPTION TO THE LOCKOUT/TAGOUT STANDARD Lockout/Tagout & Employee Protection (CPL:Pg. 2-16) Employee Protection for Service & Maintenance Activity is achieved by: Apply Full LOTO I/A/W 29 CFR ; Complying with the minor servicing exception to the LOTO standard ( (a)(2)(ii)) Machine Guarding Must provide effective employee protection. Utilizing the cord and plug connected equipment or hot tap exemptions i.e., (a)(2)(iii)(A) and (a)(2)(iii)(b); Complying with the machine or equipment testing or positioning requirements of (f)(1); Machine Guarding Must provide effective employee protection. LOTO Scope (a)(2)(ii) Normal production operations are not covered by this standard (See Subpart O of this Part). Servicing and/or maintenance which takes place during normal production operations is covered by this standard only if: An employee is required to remove or bypass a guard or other safety device; or An employee is required to place any part of his or her body into an area on a machine or piece of equipment where work is actually performed upon the material being processed (point of operation) or where an associated danger zone exists during a machine operating cycle. 6

7 Minor Servicing Exception Exception to paragraph (a)(2)(ii) Minor tool changes and adjustments, and other minor servicing activities, which take place during normal production operations, are not covered by this standard if they are routine, repetitive, and integral to the use of the equipment for production, provided that the work is performed using alternative measures which provide effective protection (See Subpart O of this Part). Lockout/Tagout & Machine Guarding Employee Exposure Servicing & Maintenance Activity 29 CFR Normal Production Operations Subpart O 29 CFR Employee Exposure Lockout/Tagout & Machine Guarding Employee Exposure Servicing & Maintenance Activity 29 CFR M S E Normal Production Operations Subpart O 29 CFR Employee Exposure 7

Minor Servicing Exception In order to take advantage

effective alternative protection in lieu of LOTO.

Guards & Safeguarding Devices to ELIMINATE employee

maintenance activities: Do not require extensive

8 Minor Servicing Exception In order to take advantage of the limited exception, an employer must provide effective alternative protection in lieu of LOTO. Lockout/Tagout & Machine Guarding Guarded Guarded Guards & Safeguarding Devices to ELIMINATE employee exposure during the servicing and maintenance activity. Minor Servicing Exception Minor servicing and/or maintenance activities: Do not require extensive disassembly of the machinery/equipment. Can be accomplished safely with effective production-mode safeguards, (Subpart O). 8

9 Minor Servicing Exception (CPL:Pg. 3-26) Activities requiring machine or equipment shutoff and disassembly, such as changing a machine tool or cutting blade, usually take place outside of the normal production process and require energy isolating device LOTO in accordance with Changing Table Saw blade. Changing Grinding Wheel, etc. Replacement of machine or equipment components normally is not considered a routine maintenance function that can be safely accomplished when a machine or piece of equipment is operating. belts, valves, gauges, linkages, support structure, etc. -- Service/ Maintenance Activity/ EE Exposure to Hazard Region V Minor Servicing ( (a)(2)(ii)) Decision Flow Chart Normal Production Operation? YES Service/ Maintenance Inherent & Minor?* YES Effective Protection In Use? ** YES Exception Applies to Service/Maintenance NO NO NO Lockout Applies to All Service/Maint Lockout Applies Lockout Applies * Inherent & Minor - Activities must be necessary to allow production to proceed and be: Routine: The activity must be performed as part of a regular and prescribed course of procedure and be performed in accordance with established practices. Repetitive: The activity must be repeated regularly as part of the production process or cycle. Integral: The activity must be inherent to the production process. ** Employer must demonstrate that the alternative measures provide effective protection from the hazardous energy. (Subpart O; ANSI B ; etc.) MSE Operator Initiated Safety Is it acceptable to have the employee follow a procedure to place the machine in a safe mode, manual mode or pause the operation as a part of the MSE effective protection? NO! With the exception of certain low risk equipment and tasks. 9

10 Westvaco Corporation Decision (CPL:Pg. 3-26) OSHA issued a citation alleging a serious violation of because an employer did not lockout or tagout the slotter section of a printer/slotter machine. Adjustments to both the printer section and the slotter section had to be made for each order. The average number of orders run per day was three or four and each order change required set-up adjustments taking between 15 and 45 minutes to complete. Westvaco Corporation Decision What did the OSHRC decide and why? Rejected the employer's assertion that set-up activities associated with this equipment constituted minor servicing within the scope of the exception. Commission Concluded setting up does not occur during normal production operations work performed before the normal production operation is not covered by the exception Westvaco Corporation Decision While not reaching the questions of whether the activities were minor [as are included in this exception] or whether the alternative protection was effective, the Commission concluded that adjustments made while the machine was being set-up were not adjustments made during normal production operations. 10

11 MSE Operator Initiated Safety Must have a guard or safety device, properly selected and applied based on generally accepted good engineering practices. (ANSI B11.19) A procedure that involves and requires the employee to initiate the safe condition is an Administrative Control. Most Effective Least Effective Hierarchy of Control PROTECTIVE MEASURE Elimination or Substitution Engineering Controls (Safeguarding/Safeguards) Awareness Means Training and Procedures (Administrative Controls) Personal Protective Equipment (PPE) EXAMPLES Eliminate human interaction in the process. Eliminate pinch points (increase clearance) Automated material handling. Etc. Guards Fixed, Interlocked, Adjustable, Etc. Interlocks Presence Sensing Devices - light curtains, safety mats, area scanners, etc. Two Hand Controls and Trip Devices Lights, beacons, and strobes Computer Warnings Signs and Labels Beepers, Horns, and Sirens Safe Work Procedures Safety Equipment Inspections Training Lockout/Tagout/Tryout Safety glasses/face Shields Ear Plugs Gloves Protective Footwear Respirators MSE Operator Initiated Safety Intrp Letter August 24, 2005 In low risk minor servicing applications, such as changing a tool bit on a milling machine or a drill bit on a drill press, where the activity meets all of the criteria contained in the minor servicing exception, servicing activities may be performed using local disconnects or control switches that: 11

Examples Of Effective Alternative Protection (Minor Servicing Exception) (CPL: Pgs. 3-29 thru 3-32) Changing a mixing blade on a vertical mixer or a drill bit on a single-spindle drill press.

12 Examples Of Effective Alternative Protection (Minor Servicing Exception) (CPL: Pgs thru 3-32) Changing a mixing blade on a vertical mixer or a drill bit on a single-spindle drill press. machine's electrical disconnects or control (e.g., on/off buttons or emergency stops) switches: 1. Are properly designed and applied in accordance with recognized and good engineering practice; and 2. Control all the hazardous energy and are placed in an off position; and 3. Are under the exclusive control of the employee performing the task. Examples Of Effective Alternative Protection (Minor Servicing Exception) (CPL: Pgs thru 3-32) Removal of a part that is stuck (jammed) in a plastic injection molding machine. Completed a cycle and is shutoff (using the stop push button). Opening interlocked sliding operator gate guard prevents the machine from cycling. Examples Of Effective Alternative Protection (Minor Servicing Exception) (CPL: Pgs thru 3-32) The employee is positioned such that the interlock operator-gate provides the employee with sufficient protection an interlock gate guard is not adequate protection if the employee's entire body is inside the guard area Injection molding machine safety systems are designed, inspected, tested, maintained, and operated in accordance with recognized and generally accepted good engineering practices; and Means of control of the machine remain in the exclusive control of the person afforded the protection. 12

13 Minor Servicing Exception (CPL:Pg. 3-29) An employer who is claiming that a machine servicing activity is exempted by the minor servicing exception must demonstrate that they meet each and every element of this exception. See Falcon Steel Co., 16 BNA OSHC 1179 (No , 1990) Examples Of Effective Alternative Protection (Minor Servicing Exception) Task Creep Mold opened too soon or a stuck plastic part melted or became stuck such that LOTO is required because other-than minor cleaning must be performed. e.g., prying, pulling, scrapping, and/or chipping) or even machine component (e.g., die) disassembly This now requires LOTO Lockout/Tagout & Employee Protection (CPL:Pg. 2-16) Employee Protection for Service & Maintenance Activity is achieved by: Using effective machine guarding, in compliance with Subpart O, that eliminates or prevents employee exposure from the hazardous energy associated with the machines or equipment; 13

14 Lockout/Tagout & Machine Guarding (CPL:Pg. 2-18) Point of operation requirements for machines, (a)(3)(ii) requires point of operation danger zone guarding in conformity with any appropriate or applicable standard that has been adopted as or incorporated by reference into an OSHA standard. In the absence of such standards, the guarding device must prevent (and not just warn or signal employees of the impending hazard) the operator from having any part of his or her body in the danger zone during the operating cycle. Machine Guarding/ANSI B (CPL:Pg. 2-26) OSHA will consider adherence with: 1) guards; 2) safeguarding devices; As primary safeguarding methods compliant with Subpart O. Effective Employee Protection What is Effective Employee Protection or Effective Machine Guarding? American National Standard for Machine Tools Performance Criteria for Safeguarding -- ANSI B

15 Safeguarding (CPL:Pg. 1-9) Safeguarding Protective Device in the 2003 ANSI standard. Safeguarding (protective) device: A device that detects or prevents inadvertent access to a hazard. Devices that detect, but do not prevent employee exposure to machine hazards (e.g., through one of the four methods in (a) through (d) above), do not comply with the machine guarding provisions contained in Subpart O, when guards or safeguarding devices are feasible. OSH Review Commission Section (a)(1) is a general machine guarding standard that applies to all machinery not otherwise covered by Subpart O. The guarding required must be provided by by a a device that does not not allow allow reliance upon upon the skill the skill or or attentiveness of employees. of employees. It is It is intended to eliminate danger from unsafe operating procedures, poor training or employee inadvertence. Cincinnati Incorporated, OSHRC Docket No , Final Order Date 10/02/00 Machine Guarding/ANSI B (CPL:Pg. 2-26) These methods, by design, do not prevent employees from placing or having any part of their bodies in the hazardous machine areas: Awareness devices; Safeguarding (work) methods; Safe work procedures. These methods provide a lesser degree of employee protection and are considered to be secondary control measures during normal production operations. 15

16 Hierarchy of Control Most Effective Least Effective PROTECTIVE MEASURE Elimination or Substitution Engineering Controls (Safeguarding/Safeguards) Awareness Means Training and Procedures (Administrative Controls) Personal Protective Equipment (PPE) EXAMPLES Eliminate human interaction in the process. Eliminate pinch points (increase clearance) Automated material handling. Etc. Guards Fixed, Interlocked, Adjustable, Etc. Interlocks Presence Sensing Devices - light curtains, safety mats, area scanners, etc. Two Hand Controls and Trip Devices Lights, beacons, and strobes Computer Warnings Signs and Labels Beepers, Horns, and Sirens Safe Work Procedures Safety Equipment Inspections Training Lockout/Tagout/Tryout Safety glasses/face Shields Ear Plugs Gloves Protective Footwear Respirators Complimentary Safeguarding Equipment Equipment That Augments Safeguarding Devices: Safety Blocks, Slide Locks, Chain Locks, and Locking Pins Workholding Equipment Enabling Devices Stopping Performance Monitors Safety Interface Modules Monitoring Safety Relays Safety PLCs Safety BUS Systems Emergency Stop (E-Stop) Devices Pushbuttons Pull Cords (Cable Pulls, Trip Wires) Body Bars Trip Rods Footswitches (without a mechanical guard) Hand Tools Types of Safeguarding Mechanical solutions that physically prevent or restrict access: Fixed Guards Safe Openings in Fixed Guards Adjustable Guards Moveable/Self Adjusting Guards Pullbacks Mechanical Restraints 16

17 Types of Safeguarding Mechanical solutions that prevent access and cycle initiation (Interconnected or Interlocked): Interlocked Guards (With or W/O Guard Locking) Type A&B Moveable Barriers (i.e. Gates) Moveable/Automatic Screens Automated Doors Probe Detection Interlocks and Guarding Devices What do these devices have in common? They are all connected to the machine controls and generate/send a command to stop or prevent hazardous motion. This Protective (Safety) Stop command is sent through the protective stop circuit. (ANSI B : Clause 6.2.1) Design of the SRP/CS One strategy used to meet these requirements is to design the system with; Redundancy, and Monitoring to ensure that redundancy is maintained. This design strategy is called Control Reliability and it is used to describe the integrity of the safety rated control system. 17

ISO 13849-1 Requirement Highlights ISO 13849-1 provides safety requirements and guidance on the principles for the design and integration of safety-related parts of control systems (SRP/CS),

18 Safety Related Parts of Control System (SRP/CS) Are the machine s SRP/CS Control Reliable? What is the other question we should be asking? What is the Performance Level (PL) or Safety Integrity Level (SIL) of the machine s SRP/CS? This will tell us how well the Safety-Related Function performs. ISO Requirement Highlights ISO provides safety requirements and guidance on the principles for the design and integration of safety-related parts of control systems (SRP/CS), including the design of software. Topics include: Performance Levels Categories Diagnostic Coverage Common Cause Failures MTTFd Safety Functions Software based parameterization Fault considerations and Fault exclusions 53 Categories The common misunderstanding Safety Categories ONLY describe what happens if something goes wrong. They are NOT a measure of reliability, quality, or safety. Instead, they help answer the question So.If this thing fails, will the machine still shut down? The higher the category, the more measures are in place to ensure the safeguarding device does what it is supposed to do. A higher category does NOT a mean a machine is Safer 54 18

19 Performance of the Safety-Related Function (ANSI B : Clause 6.1) When a single failure occurs, and it or another subsequent failure would lead to the inability of the safety-related function(s) to respond to a normal stop command or an immediate stop command, the safety-related function shall: Performance of the Safety-Related Function (ANSI B : Clause 6.1) Until the failure is corrected or until the control system is manually reset; Prevent initiation of hazardous machine motion; or Initiate an immediate stop command and prevent re-initiation of hazardous machine motion; or Prevent re-initiation of hazardous machine motion at the next normal stop command. Understanding Safety Categories Categories range between B through 4. Oversimplified, they build off each other to ensure faults don t lead to unsafe states: Category B: The use of basic safety principles The use of standard components with no fault detection or fail-safe measures Category 1: Category B plus the use of well-tried components or safety-rated devices instead of standard components. Category 2: Category B plus periodic monitoring no action required (e.g. check engine light on car). Category 3: Category B plus no single fault can lead to an unsafe state, single faults must be identified (e.g. redundancy) Category 4: Category B plus no accumulation of faults can lead to an unsafe state or all faults must be individually identified (e.g. every safety device has its own safety monitoring relay) 57 19

Diagnostic Coverage Feedback Feedback 58 Control Reliability Performance Level Safety Integrity

20 Understanding Safety Categories Example Safety Function Safety Category Direct Drive or Positive Opening Mechanically Linked Contacts Periodic Testing Periodic Testing Higher Diagnostic Coverage Feedback Feedback 58 Control Reliability Performance Level Safety Integrity Level (Table 4 ANSI B : Clause ) Acceptable Levels (Table 4 ANSI B : Clause ) 20

Machine Safety Statistics: Control System Failures HSE: Out of Control 978 0 7176 2192 7 61 Today s Machine Safety Landscape Most manufacturers today are in one of these categories: Avoidance:

We haven t had an accident, haven t had a citation we are good to go Illusion of Safety: There has been a valiant effort to use technology and new guarding methods to provide increased safety, but

21 Machine Safety Statistics: Control System Failures HSE: Out of Control Today s Machine Safety Landscape Most manufacturers today are in one of these categories: Avoidance: Machines are not fully safeguarded or there has been a minimal attempt to safeguard. We haven t had an accident, haven t had a citation we are good to go Illusion of Safety: There has been a valiant effort to use technology and new guarding methods to provide increased safety, but ultimately is resulting in an illusion of safety Fort Knox: Limited understanding in technology, standards, and regulations causes an overly guarded, overly restrictive, high cost, and productivity limiting safety solution 62 Programmable logic controllers (PLCs)? (CPL:Pg. 1-6) PLC devices are NOT considered energy isolating devices for purposes of the LOTO standard. Safety functions, such as stopping or preventing hazardous energy (motion), can fail due to component failure, program errors, magnetic field interference, electrical surges, improper use or maintenance, etc. 21

22 What To Look For 22

Machine Safeguarding and Lockout/Tagout Practices

Manufacturing Machine Safeguarding and Lockout/Tagout Practices On a daily basis, manufacturing employees may be asked to work with or interact with a wide variety of machinery and equipment. Some machines