Lockout/Tagout – Alternative Methods (Risk Assessment)

W. Jon Wallace, CSP, MBAWorkplace GroupO: 919.933.5548E: jwallace@workplacegroup.net

Compressed Springs

Is this an energy isolating device?

Human Safety Blocks?

Equipment-Specific Lockout Procedures: 1910.147(c)(4)

What about tasks you perform routinely where the equipment must remain energized?

Alternative Methods – Risk Assessment

A word about risk

Risk: Severity X Frequency X Probability

Plastic Injection Molding Machine

Industrial Robot

Example of equipment-retrofit:

References for performing Risk Assessment:

• ANSI Z244.1: Control of Hazardous Energy - Lockout/Tagout and Alternative Methods.

• ANSI/RIA R15.06: Industrial Robots and Robot Systems - Safety Requirements.

• ANSI B11.19: 2010 Performance Requirements for Safeguarding

• OSHA CPL: 02-00-147: The Control of Hazardous Energy – Enforcement Policy and Inspection Procedures

Performing Risk Assessment:

1. Identify all tasks: Tasks where equipment must remain energized.

2. Identify Hazards: Electrical; gravity; chemical; pneumatic; etc.

3. Assess Potential Consequences: Worst case scenario (injury).

Performing Risk Assessment (Cont’d):

4. Assess potential exposure to hazards.

5. Assess probability of occurrence.

6. Evaluate the risk.

7. Achieve an acceptable level of risk.

Let’s Perform an Example:

• Employee changes tooling on robot once per shift. Existing interlock category: R2C

A Word about interlocks (per ANSI/RIA R15.06) :

Category Circuit Performance

R1 Control Reliable

R2A Control Reliable

R2B Single Channel with monitoring

R2C Single Channel

R3A Single Channel

R3B Simple (Simple safety circuit)

R4 Simple (Simple safety circuit)

How to determine interlock: Manufacturer and E&I folks.

Increasing Sophistication

Back to our example:

Employee changes tooling on robot once per shift. Existing interlock category: R2C

Task Hazard(s) Severity Exposure (Frequency)

Avoidance Protective Measures

Risk Reduction Required

Changing tooling on robot.

Struck by (moving robot).

S2 (Serious injury)

E1 (Infrequent)

A2 (Not likely to move out of way)

Interlock: R2C

R2B

LEGEND:

Summary: Interlock needs to be upgraded from R2C to R2B.

Interlock requirement (ANSI/RIA R15.06)

Remember: S2; E1; A2.

Putting it all together:

• Evaluate your lockout/tagout program.• Implement upgrades as needed.• Inventory tasks where equipment must

remain energized.• Perform risk assessment using ANSI

Lockout and Robotic standards.• Upgrade safeguards as needed.

Conclusion

Question/Comments?