Program Objectives In light of industrialization trends across the globe, new hazards are constantly introduced in many workplaces. This program aims to provide Young Safety Professionals (YSPs) from diverse backgrounds with the requisite skill to address the health and safety hazards in the modern workplace.

1. Risk Assessment Program
Trainer: Mr. Muizz Anibire, MSc
Tel: +966501296203, Email: muizzanibire10@gmail.com

2. Risk Evaluation
 Risk evaluation is the process of comparing estimated risk levels
with an established baseline - the defined risk criteria in context
of the assessment - to determine the appropriate action (ISO
31010/ANSI/ASSE Z690.3-2011).
 Risk is evaluated using the estimated risk levels of consequences
and likelihood of occurrence developed in the hazard/risk
identification and risk analysis phases.
 The understanding of the nature and magnitude of risk derived
from the risk analysis is used to decide whether a particular risk is
acceptable and what future actions are required.

3. Risk Assessment Criteria
 Risk criteria are the reference points against which the
significance of risk are evaluated and measured. Such criteria are
derived from the organization’s culture and industry, external and internal
context, applicable laws, standards and other requirements.
 Such criteria must be clearly defined and communicated by an
organization to consistently evaluate operational risks, and make
proper risk-based decisions.
 A number of existing risk criteria measures are available,
however, it is essential that an organization carefully select
and/or develop its own risk criteria to reflect its values, goals,
industry setting, and overall culture.
 In general, risk criteria should include a risk scoring system that
includes risk factors, defined scales of risk levels and a risk
matrix for an organization to measure risk for the purpose of
prioritizing and making proper decisions.

4. Risk Assessment Criteria
 The primary purpose of risk assessment is to identify hazards,
and assess and reduce their risk to an acceptable level.
 To achieve this, a measurement system that includes a baseline
(an organization’s acceptable risk level) and a method of scoring
(a risk scoring system) must be established.
 Thus, risk criteria must begin with these two risk factors:
likelihood and severity.
 Several other risk factors can be added to further define risk such
as exposure or frequency of exposure, duration of exposure,
vulnerability, failure detectability, control reliability, and
prevention effectiveness.

5. Risk Assessment Matrices
 A key part of a risk scoring system is the risk assessment matrix.
 Many organizations use risk assessment matrices or heat maps
based on defined risk criteria to visually compare risk levels
within the graduated risk level categories.
 A matrix helps visualize and communicate risk levels to decision
makers by providing a means for categorizing combinations of
likelihood and severity and their risk levels.
 They are often used as a screening tool when there are many
risks to evaluate.
 Risk assessment models and their matrices may be classified as
qualitative, semi-quantitative or quantitative.
 When defining the risk criteria and risk scoring system to be used,
stakeholders must take into consideration the level of detail desired, and
data and resources available.

6. Risk Assessment Matrices
 Qualitative risk models are based on qualitative or subjective
descriptions rather than numerical or statistical data, and require
less precise information to be developed and used.
 Qualitative risk models define severity of consequence, likelihood
and level of risk using descriptive words such as “high”,
“medium” and “low” which are evaluated according to qualitative
criteria.
 Semi-quantitative risk models use qualitative data; however the
values are expressed as numerical risk ratings using a formula to
produce a risk level or score.
 Risk level scores produced can be linear or logarithmic based on
the formula selected. One advantage of a semi-quantitative
model is that more precision can be given by adding definitions
that include some numerical ranges for severity of consequences
and likelihood of occurrence.

7. Risk Assessment Matrices
 Quantitative risk models use data to define values for severity of
consequences and likelihood of occurrence, and produce risk
level values in specific numerical units.
 As described in ANSI Z690.3, ‘full quantitative analysis’ may not
be possible or desired if there is insufficient information or data
available about the system or activity to be analyzed, or the
efforts required exceed the needs of the assessment.

8. Risk Assessment Matrices
Qualitative Risk Matrix (5x4) Example from
MIL-STD 882E
Semi-quantitative Risk Matrix (5x6) Example from
ANSI/ASSE Z690.3-2011
Numerical Scoring Risk Matrix (5x5) Example from
ANSI/ASSE Z590.3-2011 (R2016)

9. Risk Assessment Matrices
Qualitative risk matrix example

10. Risk Assessment Matrices
Semi-quantitative risk matrix example
 Severity of Injury or Illness Consequence 
Likelihood of
Occurrence or
Exposure for
select unit of Time
or Activity
Negligible
(1)
Marginal
(2)
Critical
(3)
Catastrophic
(4)
Frequent
(5)
5 10 15 20
Probable
(4)
4 8 12 16
Occasional
(3)
3 6 9 12
Remote
(2)
2 4 6 8
Improbable
(1)
1 2 3 4

11. Risk Assessment Matrices
Risk matrix example –
MIL-STD-882E, the Department of Defense Standard Practice for System
Risk Assessment Matrix
Severity
Probability
Catastrophic
(1)
Critical
(2)
Marginal
(3)
Negligible
(4)
Frequent
(A) High High Serious Medium
Probable
(B) High High Serious Medium
Occasional
(C) High Serious Medium Low
Remote
(D) Serious Medium Medium Low
Improbable
(F) Medium Medium Medium Low
Eliminated
(E) Eliminated

12. Risk Assessment Matrices
Risk matrix example – Numerical grading and scoring

13. Risk Assessment Matrices
Standard/
System
Values Risk Factors Matrix
Type
Risk Levels/Categories
ANSI B11.0
-2010
Qualitative Probability (P)
of Occurrence
x
Severity (S) of
Harm
4 x 4 4 risk levels
 High
 Medium
 Low
 Negligible
ANSI Z10-
2012
Qualitative Likelihood (L)
or Exposure
x
Severity (S) of
Injury or Illness
5 x 4 4 risk levels with actions
required
 High
 Serious
 Medium
 Low
ISO 31010/
ANSI
Z690.3-2012
Semi-
quantitative
Likelihood (L)
x
Consequence
(C)
5 x 6 5 risk levels
 I (Highest)
 II
 III
 IV
 V (Lowest)
MIL-STD
882E
Qualitative Probability (P)
x
Severity (S)
6 x 4 5 risk levels
 High
 Serious
 Medium
 Low
 Eliminated
ANSI
Z590.3 PtD
Semi-
quantitative
Severity (S)
x
Probability (P)
5 x 5 4 descriptive risk levels
 Very high risk
 High risk
 Moderate risk
 Low risk
Examples of risk matrices and scoring systems

14. Risk Reduction – As Low As Reasonably Practicable/Acceptable
ISO 31010 presents a simple concept of dividing risks into three
bands used in evaluating risk. These categories can be described as
follows:
 unacceptable - where the activity is to be avoided or reduced
before continuing
 marginal or ALARP – where the costs and benefits of
further risk treatment are evaluated before continuing
 acceptable – where the risk level is considered negligible
requiring no further risk treatment
Acceptable risk level can be defined as the risk level an organization
is willing to tolerate in its current context. Acceptable risk levels, as
well as unacceptable levels tend to be lowered as an organization
becomes more effective in their risk management efforts, reducing
risk and improving control technologies.

15. Risk Reduction – As Low As Reasonably Practicable/Acceptable
The ALARP Model from ANSI/ASSE Z690.3-2011

16. Risk Reduction – As Low As Reasonably Practicable/Acceptable
Weighing all relevant matters including:
1. the likelihood of the hazard or the risk
occurring; and
2. the degree of harm that might result; and
3. what the person concerned knows, or
ought reasonably to know, about—
 the hazard/risk; and
 ways of eliminating/minimizing the
risk; and
4. the availability/suitability of ways to
eliminate/minimize the risk; and
5. after assessing the extent of the risk and
the available ways of eliminating or
minimizing the risk, the cost associated
including whether the cost is grossly
disproportionate to the risk.

17. Risk Reduction – As Low As Reasonably Practicable/Acceptable

18. Risk Reduction – As Low As Reasonably Practicable/Acceptable

19. Risk Reduction – Hierarchy of Controls (HOCs)
The Hierarchy of Controls is a model
for identifying the risk reduction
effectiveness of control types.
It is defined by ANSI Z590.3,
Prevention through Design as:
A systematic approach to avoiding,
eliminating, controlling, and reducing
risks, considering steps in a ranked and
sequential order, beginning with
avoidance, elimination, and substitution.
Residual risks are controlled using
engineering controls, warning systems,
administrative controls, and personal
protective equipment.
The most effective risk reduction is achieved
through avoidance of the risk or elimination by
design or redesign. Lower level controls should
only be selected after practical applications of
higher level controls are considered.

20. Risk Reduction – Hierarchy of Controls (HOCs)
A common example of the Hierarchy of Controls

21. Risk Reduction – Hierarchy of Controls (HOCs)
Two Stage Iterative Approach to the Hierarchy of Controls and Risk Reduction from ANSI
B11.0-2015 – Safety of Machinery

22. Risk Reduction – Hierarchy of Controls (HOCs)

23. Risk Reduction – Hierarchy of Controls (HOCs)
ANSI Z10-2012 (R2017) Hierarchy of Controls Model

24. Risk Reduction – Hierarchy of Controls (HOCs)