1. Industrial Automation
Safety Rules For Different Zones in
Industrial Automation
Presented by
Manoranjan Sahoo EI
Under the guidance of
Mr. Bhawani Shankar Pattnaik

2. greater than the limit risk.
Safety is a situation, whereby the risk is not
greater than the limit risk.
Risk is a combination of the probability and the
degree of the possible injury or damage to health
in a hazardous situation.
Safety is relative.
There is no such thing as 100% safety.
INTRODUCTION

3. The Margin Between Danger and Safety
Danger: The risk is greater than the limit risk.
Safety: The risk is not greater than the limit risk.
Limit risk: The maximum acceptable level of risk.
Residual risk: Risk remaining after safety measures has taken.

4. Prevention of accidents
Why Safety?
Prevention of accidents
Protection in the workplace.
Cost effective.

5. DIFFERENT SAFETY STANDARDS
ANSI:- American National Standards Institute.
IEC:- International Electrotechnical Commission.
DIN:- Deutsches Institute of Normung
OSHA:- Occupational Safety and Health Administration
EU: European economic Union (EN-standards)

6. Safety Integrity Level Probability of failure on demand
SAFETY ZONES
Safety Integrity Level
Probability of failure on demand 1
>=10^-5 to <10^-4 2
>=10^-4 to <10^-3 3
>=10^-3 to <10^-2 4
>=10^-2 to <10^-1
Relation between SIL and PFD
Relation between SIL and SC

7. SAFETY RULES
Flow chart for the iterative process to achieve safety

8. Risk analysis: Determination of the Limits of Machinery
All phases of machinery life
The limits of machinery including the intended use
The full range of foreseeable uses of the machinery
The anticipated level of training, experience, and ability of the user
Exposure of other persons to the hazards of the machinery
Hazard Identification
Risk Estimation

9. Risk Evaluation and Reduction
Safe machinery design
Protection measures for the risks that can’t be eliminated
Inform users of the residual risks
Information, instruction, training and supervision
Use of Personal Protection Equipment

10. Area Guarding Switch off power when a person enters the hazard area
Prevent switching on power when a person is in the hazard area.
Trip and Area guarding
Trip and presence sensing device

11. Choice of Protective Measures
1. Preventing access during dangerous motion
Fixed Guards
Movable Guards
Two-Hand Controls
Preventing dangerous motion during access.
Photoelectric Light Curtains
Pressure Sensitive Safety Mats
Pressure Sensitive Edges

12. Fixed guard
Movable guard
Two Hand control

13. Photoelectric Light Curtain
Pressure Sensitive Safety Mat
Pressure Sensitive Edge

14. Emergency Stops
Telescopic Trip Switches
Cable Pull Switches

15. Safety light curtains fall into three product families
1. Point of Operation Control
2. Area Access Control

16. Safety Light Curtains Function Advantages Greater productivity
Ergonomically sound
Frequent and easy access
3. Perimeter Access Control

17. Blanking- Fixed and Floating
Floating blanking
Fixed Blanking

18. Muting The muting conditions defined in IEC 61508:
a. Muting is only permitted to be activated during the time span of the working cycle
b. Muting must be performed automatically.
c. Muting must not depend on a single electrical signal.
d. Muting must not depend completely on software signals.
e. The muting signals, if they occur as part of an invalid combination, must not permit any muting state.
f. The muting state is removed immediately after the pallet has passed through

19. Muting

20. R = I + d How to choose the device 3 characteristics of a device:
Resolution
The height of the protected area
The safety distance
R = Resolution
I = Inter-axis distance
d = Diameter
Resolution visualization
Resolution for body Protection

21. The height of the protected area
HCA = HSA+2I
Where
HCA = Height of the controlled area
HSA = Height of the sensitive area
I = Inter Axis distance

22. The safety distance OSHA Formula:
Ds = 63 X TS where Ds= Safety Distance
63 = Recommended hand speed in in/sec
TS = Total stop time in Sec
ANSI Formula:
Ds = K x (Ts + Tc + Tr + Tbm) + Dpf
Ds = The minimum safe distance
K = 63 (hand speed in in/sec)
Ts = Stopping time of machine, in seconds
Tc = Control circuit response time in seconds
Tr = Light curtain response time
Tbm = Response time of a brake monitor
Dpf = Depth penetration factor
EN 1050 Formula:
S = (K x T) + C K = 1600mm/sec assumed operator speed
T = The overall stopping time of the system
C = Depth of penetration
S = Safety distance

23. High efficiency is required High accuracy is required
CONCLUSION
High efficiency is required
High accuracy is required
Complexity increases
Terrorism increases
Safety is required

24. THANK YOU