UNDERSTANDING SLO: SAFE LASER OFF SAFETY CONSIDERATIONS ACCORDING TO EN ISO 13849-1:2008
102
AREX™ 400
Example 2
Risk Analysis of a fully automatic laser processing machine that operates only when pro-
tection system is disengaged.
•
Operative cycle: 500 pcs/hour, 3 shifts (8h/shift) 350 days /year
•
Dedicated enclosures prevent laser emission also during parts loading / unloading
•
An interlocked door is dedicated to
maintenance and blockage recovery
•
Operator are
NOT SKILLED
on laser risks and do
NOT
have
DPI
•
In case of access line is stopped and restarted
LASER RISK ASSESSMENT:
HAZARD, direct scattered laser radiation:
•
RISK SEVERITY: SEVERE (irreversible eye damage)
•
RISK FREQUENCY:
SELDOM
(1/week)
•
AVOIDANCE PROBABILITY:
NOT POSSIBLE
RISK REDUCTION:
INTELOCKED DOOR
Estimation of PLr for door interlock safety function
•
SEVERITY: SEVERE
S2
•
FREQUENCY: SELDOM
F1
•
POSSIBILITY OF AVOIDING HAZARD: NOT POSSIBLE
P2
Severity of injury (S)
S1
Slight (normally reversible injury)
S2
Serious (normally irreversible injury or death)
Frequency and/or exposure time to hazard (F)
F1
Seldom to less often and/or exposure time is short
F2
Frequent to continuous and/or exposure time is long
Possibility of avoiding hazard or limiting harm (P)
P1
Possible under specific conditions
P2
Scarcely possible
PLr = PLd
Restart: manual reset
Door Switch
Safety Controller
Arex™ 400 SLO - Safety Circuit
Input
Logic
Output
PLr=PLd
