Risk Ass. Difficult

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Revised Risk Assessment Method for Use with OHSAS 18001:2007Hisao TOYODA

Owner, Toyoda Consultant, [email protected]

24-12, 3-chome, Kandaiji, Kanagawa-ku, Yokohama 221-0801, Japan

Abstract: In APSS 2009 the author submitted a paper entitled Proposed Risk Assessment Method for Use with OHSAS

18001:2007. A revised version of the methodology for risk assessment is presented after taking into account the last four years

experiences of the application of the original method. The new method also uses a repetitive procedure intensively for risk reduction.The framework of the method is consistent with the steps for the risk assessment specified in OHSAS18001 and they are

implemented in accordance with the scheme used in the original version but now considerably simplified and generalized for use inany industrial sector. The application of the risk control procedure is basically the same as the one specified in OHSAS 18002.The risk categorization and risk-based control plans recommended by BS 18004 are partly utilized. The proposed risk assessment

methodology is applicable not only for an independent execution of risk assessment itself but also for the one incorporated in theOH&S management system. For the users of the latter case, the interface between the risk assessment and management system is

carefully described elsewhere in the paper.

Keywords: ALARP, Hierarchy of controls, OH&S management system, prioritization, risk assessment, risk controls

INTRODUCTION

The risk assessment method introduced hereunder is

developed for OH&S management systems built and

operated under OHSAS 18001:2007. Although the

overall structure of the proposed method in this paper

follows the basic scheme of the original version1), the

procedure for each step has been simplified, as shown

in Fig. 1, and the entire framework was generalized so

that it can be used for risk assessments of any

industries.

The guidelines issued by the governmental agencies in

certain countries stipulate the risk controls are to be

capable of attaining ALARP level2), 3)

. Thus, to

achieve this, the risk assessment methodology has a

repetitive mechanism so that it can attain the risk level

defined as ALARP shown in Fig. 1 and Fig. 2.

Multiple repetition is seldom required. However, incase of overall risk assessments of major industrial

sectors such as manufacturing and construction where

risk level is high, repetition is necessary. Therefore,

the basic flow in Fig. 1 has been modified that

ordinary risk items are dealt with at Step 1 - Step 4.

RISK ASSESSMENT METHODOLOGY

1) Procedure for [A] in Fig. 1

For Step 1, Step 2 and Step 3, any risk assessment

procedure such as the risk matrix approach or

numerical approach is applicable and the details of

these processes are omitted here. Through the steps

referred to above, the risk assessment process is

applied for all the controls including any in place. The

results of these evaluations are stratified in 5 levels

(5-1) in the latter part of Step 3 as shown in Table

1 (extreme left).

Fig. 1 Flow chart for Risk assessment and Determining controls5)


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2) Step 4 (Initial assessment) - Question Is risk

negligible (risk level=1)?

In the first part of Step 4, Risk 1 is excluded and the

other risks (5-2) are sent through Planned

controls in Table 1 (second column from left) for risk

reduction in the latter part of Step 4.

3) Step 4 (Re-assessment) - Question Has

adequate risk level been achieved?

In accordance with the guidelines stipulated as Risk

control plan in Table 1 (center) for the relevant risk

level decided in Initial assessment, the planned

control corresponding to each level of risks in that

plan is determined by considering the hierarchy of

controls explained in Table 2. The risk reduction

scheme for the relevant level is summarized in Table 1

(center) by partly utilizing the risk-based control plans

recommended by BS 18004:2008. The resultant risks

are re-evaluated at the end of Re-assessment and they

are tabulated in 5 risk levels and categorized into U,A and B. For Risk A [4]-[2] no further reduction

is required unless specified otherwise and Risk B [1]

stays as it is as shown in Table 1 (center right) since

all of these risks are in ALARP zone or in the lower

category.

Table 1 Risk reduction process and Prioritization of risk assessment results


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Fig. 2 Acceptable risk and ALARP

4) Step 5 Repetitive risk reduction ([B] in Fig.1)

Risk category U-[5] Very high which has not

achieved ALARP is subject to further risk reduction in

Step 5 by a repetitive procedure for the revised

planned controls including a review on adequacy of

the preceding assessments (Table 1 right). The

procedure itself is the same as that used in Step 4

(Re-assessment). Even if a further risk reduction is

tried in Step 5 or in the ongoing steps, there would be

certain risks in the category U which cannot be

Table 2 Risk controls

brought down into ALARP zone. They are treated as

Special risks and their definition is in Notec)

to

Table 14)

.

INTERFACE-Prioritization of risks for usein OH&S management systems

The final process at the end of the risk assessment

including the prioritization (P3, P2, P1) of its results is

presented at the right side of Table 1 (extreme right).

At the interface between the risk assessment and

OH&S management system, the prioritization for the

relevant category of risks is made in preparation for

use in 4.3.3 Objectives and programme (s) of

OHSAS 18001: 2007 although the details are

specified in the specification. As the risks are the most

important factors to constitute OH&S Objectives, the

foregoing process is a basis for the establishment of

the risk-based operation of the system.

CONCLUSION and Acknowledgement

After four years experience using the original method,

several changes have been made. The method has

been simplified and its interface with management

systems has been improved. The prototype of this

revised version has been applied to the risk

assessment of construction projects under the

management system other than OHSAS 18001: 2007,

the details of which are reported in the recentpublication

5).

The author thanks Dr. Shigeo Umezaki, Mechanical

and System Safety Research Group, National Institute

of Occupational Safety and Hearth, Japan for his

valuable advice.

REFERENCES

1) Hisao TOYODA, Proposed Risk Assessment

Method for Use with OHSAS 18001:2007,

Proceedings of APSS 2009, Osaka, Japan2) Guidelines for LSB Notification No. 0310001,

March 10, 2006, Ministry of Health, Labour and

Welfare (http:// www. jniosh.go.jp/ icpro/ jicosh-old/

english/guideline/2007/ 070612b/ html)

3) Reducing risks, protecting people, HSEs decision

making process (http://www. hse. gov.uk/ risk/ theory/

r2p2.pdf)

4) Journal of Japan Association of Occupational

Safety & Health Consultants, July 2010

5) Separate volume to Journal of Construction Safety

& Labour Affairs, June 2011, Rodo-chosakai,

Tokyo, Japan


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SUPPLEMENT ON ALARP

The guidelines of Ministry of Health, Labour and

Welfare, Japan refer to ALARP- As low as reasonably

practicable in connection with the clause 10(2) Risk

controls in Notification2)

, however, no quantitative

criteria have been given to the upper and lowerboundaries of the zone.

In UK, HSE (Health & Safety Executive) stipulates

that the actual fatality rate for workers is 1 in one

million per annum as the lower boundary of ALARP

zone in Fig. 2. On the other hand, HSE is reluctant to

specify the upper boundary. Dr. Taketoshi Taniguchi,

who used to teach at the graduate school of Osaka

University, Japan indicated the rate of 1 in ten

thousand per annum in his book Decision-making on

Environmental and Technical Risks published from

Osaka University Press.

Based on the criteria referred to above, Fig. A is

drawn with the fatality data of the manufacturing and

construction industries in Japan between 2004 and

2010, which were calculated by using the statistics

released by MHLW. The following comments are

drawn from the figure:

1) The fatality rate of Construction which is

considered to be the most dangerous sector in

Japan is higher than that of Manufacturing. Both

of them have been decreasing for the last seven

years.2) In the case of Construction, the fatality rates

scatter along the boundary indicated by Dr. T.

Taniguchi. That is, the risks of Construction are

distributed at higher levels if compared with

Manufacturing and thus its risk evaluation

criterion has to be designed to yield higher risk

levels such as Risk [5] so that they are subject to

risk reduction by making use of controls.

3) Since the risk controls higher in the hierarchy,

such as Items a, b and c in Table 2 are difficult to

employ in construction projects, especially in the

case of civil engineering works such as tunnels,

bridges, hydroelectric power plants, and rivers

which show the accident frequency rate higher

than the average for Construction, their residual

risks found as the results of risk assessment are to

be carefully disposed of. In the case of

Construction, therefore, use of the controls lowerin the hierarchy, such as Items d and e in Table 2

are inevitable and their implementation at

construction sites must be monitored extensively

so that their effectiveness is continuously

confirmed.

Even in the case of countries with no regulatory

requirements for ALARP, its concept seems to be

helpful for deciding the Acceptable risk specified in

Clause 3.1 of OHSAS 18001:2007. Its

recommended upper limit is shown in Fig. 2 for

reference.

Fig. A Fatality rate in Japan

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