An introduction to Hazardous Area Classification & Intrinsic Safety Audits/ Assessments for Dust

2. An introduction to Hazardous Area Classification
& Intrinsic Safety Audits/ Assessments
Mrs. E van der Walt
BEng Electronics, PREng
Principal Engineer
Control and Instrumentation
Mr. DJ van der Walt
BEng Electronics, PREng
CFSP, Certified Gas Practitioner
Discipline Manger, Control and Instrumentation
Gauteng and Coastal Regions

3. www.proconics.co.za
About the Authors and Presenter
Mr. DJ van der Walt
BEng Electronics, PREng
CFSP, Certified Gas Practitioner
Discipline Manager for Instrumentation and Control
Gauteng & Coastal regions
> 11 yrs experience in Control and Instrumentation
Joined Proconics PTY Ltd in 2005 after completion of my studies in
electronic engineering (B Eng. Electronics, at University of Pretoria)
Up to 2012 served as Proconics Basic Engineering Team Leader with
lead engineer experience on various multi and single discipline projects
Currently the Discipline Manager for Instrumentation and Control for
Proconics, Gauteng & Coastal regions
Registered as professional engineer , A Certified functional Safety
Professional and Certified Gas Practitioner, having executed multiple
functional safety and SANS 329 related compliance projects throughout
my career
Serving as Chairman of the SABS/TC 0165 – Industrial Process
Measurement, Control & Automation working group ,Chairman IEC TC-
65 South Africa Mirror and Vice Chair SAIMC Vaal
Mrs. E van der Walt
BEng Electronics, PREng
Principal Engineer, Control and Instrumentation
> 11 yrs experience in Control and Instrumentation
Joined Sasol Synfuels as a bursar in 2005 after completion of my
studies in electronic engineering (B Eng. Electronics, at University of
Pretoria)
Represented Sasol Synfuels (and later Sasol Group Technology) at the
Honeywell international Safety Manager Advisory board in Phoenix
Arizona, the Sasol LTD graduate development training committee and
various technology selection teams.
Joined Sasol Secunda Group Technology in 2010 lead engineer
experience on multi and single discipline projects, discipline leader on
Sasol Group Technology Cost Estimation tool, served as Sasol
functional safety specification originator , member of Hazop specification
and on the south African IEC mirror committee)
Nov 2015 joined Proconics as Principal Engineer (PR Eng.), Member of
the SANS TC 0165 working group for Industrial Process Measurement
Control & Automation

4. Why is it important?
“Electrical installations in hazardous areas possess features specially designed to render them suitable for operations
in such atmospheres. It is essential for reasons of safety in those areas that, throughout the life of such installations,
the integrity of those special features is preserved.”
” Correct functional operation of hazardous area installations does not mean, and should not be interpreted as
meaning, that the integrity of the special features referred to above is preserved..” SANS 60079-17

5. www.proconics.co.za
“The force from such an explosion can cause employee deaths, injuries, and destruction of entire buildings. For
example, 3 workers were killed in a 2010 titanium dust explosion in West Virginia, and 14 workers were killed in a
2008 sugar dust explosion in Georgia. The U.S. Chemical Safety and Hazard Investigation Board (CSB) identified
281 combustible dust incidents between 1980 and 2005 that led to the deaths of 119 workers, injured 718, and
extensively damaged numerous industrial facilities.” https://www.osha.gov/dsg/combustibledust/
Dust Hazards are real
Imperial Sugar
Company, Port
Wentworth GA.
Explosion and Fire
Feb. 7, 2008
13 Dead and Numerous
serious injuries

6. www.proconics.co.za
Secondary Explosion
Graphics from https://www.osha.gov Combustible dust awareness training

7. www.proconics.co.za
Safety of our people and plants: Relationship to the OHS Act
MT-00-ADM002_Rev1.0
Occupational Health
and Safety Act
44. Incorporation of health and safety standards in regulations
Regulations
Electrical Machinery Regulation, Electrical Installation regulation
SANS 10108
classification of hazardous locations & selection of electrical apparatus
SANS 10086-1
installation, inspection and maintenance of equipment in explosive atmospheres

8. www.proconics.co.za
Safety of our people and plants: Legislation and design lifecycle
MT-00-ADM002_Rev1.0
Maintain the
integrity
Correct
Installation
Validate the
Technology
Select the
Correct
Technology
Define the
Requirement
Hazardous
Area/ Ex
Lifecycle
Each step in the lifecycle should be executed by Competent people as defined in the
various standards and include specialist engineering knowledge in specific areas

9. www.proconics.co.za
MT-00-ADM002_Rev1.0
Hazardous
Area
Classification
Define the
Requirement
SANS 60079-10-1 Explosive atmospheres Part 10-1: Classification of
areas - Explosive gas atmospheres
SANS 60079-10-2 Explosive atmospheres Part 10-2: Classification of
areas - Combustible dust atmospheres
Hazardous
Area
Report &
Drawing
Whether the dust is
combustible or not.
Dust combustibility
can be confirmed by
laboratory tests.
Material
characteristics for
the process
concerned.
Nature of release
from particular
items of plant.
Operational and
maintenance regime
for the plant,
including
housekeeping.
Other equipment
and safety
information

10. www.proconics.co.za
MT-00-ADM002_Rev1.0
Example of Hazardous Area Classification Diagram ( Side view)

11. www.proconics.co.za
MT-00-ADM002_Rev1.0
What
Protection
Method is most
suited for your
application?
Can your device
be a source of
ignition?
Select the
Correct
Technology
Did you know the
following is included
in 60079?
Electromagnetic and
ultrasonic energy radiating
equipment such as Radio
frequency sources ,Lasers
or other continuous wave
sources and Ultrasonic
sources
Protection by
enclosure,
ignition
protection “tD”
Protection by
pressurization
“pD”
Protection by
intrinsic safety
“iD”
Protection by
encapsulation
“mD”
Graphics from
http://www.rstahl.com/
Typical Dust Protection Methods
SANS 61241 Electrical apparatus for use
in the presence of
combustible dust
SANS 60079 Explosive atmospheres
(various parts applicable to
different protection
methods)

12. www.proconics.co.za
MT-00-ADM002_Rev1.0
Verification/
Compliance of
System (for
example
intrinsic safety
calculations)
Verification/
Compliance of
individual
components
Validate the
Technology
SANS
60079-14
Explosive atmospheres Part
14: Electrical installations
design, selection and
erection
ARP 0108 Regulatory requirements
for explosion-protected
apparatus
Compliant
Design
Design for
maintainability &
special conditions
of use
Documentation
and Certification
“Verification
dossier”
Competence and
qualification
Verification
Calculations
Marking

13. www.proconics.co.za
Periodic
Inspections
Maintaining
the integrity
Initial
inspection
Correct
Installation
“The inspection activity shall be
sufficiently independent of any
immediate demands of
maintenance and/or other
activities so as not to prejudice
the reliability of any report
findings from the inspection”
SANS 60079-17
SANS 60079-14 Explosive atmospheres Part
14: Electrical installations
design, selection and
erection
SANS 60079-17 Explosive atmospheres Part
17: Electrical installations
inspection and maintenance
Types of
Inspection
Initial inspections
used to check that
the selected type of
protection and its
installation are
appropriate
Periodic inspections
visual
Periodic inspections
close (equipment
e.g. tools)
Periodic inspections
detailed (open
enclosure, tools and
test)
Sample Inspections
&Continuous
supervision
Inspection Frequencies are
regulated by legislation and
cannot be extended without
documentation and expert
advice

14. www.proconics.co.za
Audit
Management
Inspection
Tool
SANS 60079-14 Explosive atmospheres Part
14: Electrical installations
design, selection and
erection
SANS 60079-17 Explosive atmospheres Part
17: Electrical installations
inspection and maintenance