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Air Products Proposed Acetylene Production Facility Major Hazard Installation Regulations Risk Assessment Report v2.0

Ref: 0220780

June 2014

www.erm.com

MHI 0012

ENVIRONMENTAL RESOURCES MANAGEMENT AIR PRODUCTS ACETYLENE PLANT MHI

I

EXECUTIVE SUMMARY

Air Products Limited identified the proposed Acetylene Production facility

they wish to erect at Daleside, south of Johannesburg in the Gauteng Province

(hereafter referred to as the facility or the site) as having the potential to

affect the health and safety of employees as well as members of the public in

the event of a major incident. Hence there is a need to manage the risks and

ensure compliance with the Major Hazard Installation Regulations which

were promulgated under the Occupational Health and Safety Act No. 85 of

1993 in 1998 and revised in 2001 (1) . The current Major Hazard Installations

Regulations are attached in Annex B.

The proposed Acetylene Gas production facility will be situated in the

Midvaal Local Municipality, which falls within the jurisdiction of the

Sedibeng District Municipality in Gauteng. The proposed development site is

located on Stand 88 and 89 of Valley Settlements Agricultural Holdings at

Daleside. The site is approximately 7 km to the north of Meyerton and

situated between the M61 (Springbok Road) and the R 59. The site can be

accessed via Tilliet Road, just off the M61 (refer to Figure 1.1). The total area of

the site is 4 ha.

The site is largely undeveloped and is currently zoned for industrial purposes

and is bound by Tilliet Road to the east, a manufacturing facility to the north,

vacant and undeveloped land to the west and another manufacturing facility

to the south.

In this Acetylene manufacturing plant, acetylene is produced by reaction of

calcium carbide with water. The acetylene gas is the cleaned, compressed and

filled into cylinders. These cylinders are filled with acetone and packing rings

and the acetylene is dissolved in this liquid.

The Air Products Acetylene Production facility will be developed in a phased

approach, with 2 defined phases:

Phase 1:

The first phase of the project will encompass 1 acetylene generator vessel,

6 compressors and 2 filling halls with a total projected production capacity

of 14 400 m3/day

Phase 2:

The second phase of the project will involve the duplication of the Phase 1

section of the project and will thus involve the addition of 1 acetylene

generator vessel 6 compressors and 2 filling halls which will raise the total

projected production capacity of the site to 28 800 m3/day.

(1) Regulation R.692 Occupational Health and Safety Act (85/1993): Major Hazard Installation Regulations.

ENVIRONMENTAL RESOURCES MANAGEMENT AIR PRODUCTS ACETYLENE PLANT MHI

II

Major transport routes in close proximity to the site:

The R59 Sybrand Van Niekerk Freeway is located approximately 700

m to the west of the site

There are no other registered Major Hazard Installations in the area of the

proposed Air Products site.

The aim of the project was to undertake a Quantified Major Hazard

Installation (MHI) Risk Assessment of the proposed Air Products site, with the

objective to assess the risk to people off site via the Fatality approach.

FATALITY - LOCATION SPECIFIC INDIVIDUAL RISK

Figure 1 represents the location specific individual risks (LSIR) for

hypothetical persons located indoors. It can be seen that none of the risk

contours extend beyond the proposed Air Products Acetylene Plant site

boundaries.

Figure 2 represents the location specific individual risks (LSIR) for persons

located outdoors. Once again it can be seen that none of the risk contours

extend beyond the proposed Air Products Acetylene Plant site boundaries.

The main reason for the differences in risk levels for those indoors as opposed

to those outdoors is primarily due to the fact that the worst case scenarios of

explosions involving loss of containment of acetylene gas cause high fatalities

to individuals located indoors as opposed to those outdoors due to building

collapses.

Figure 1 Location Specific Individual Risks of Fatality Contours for Persons Located Indoors

Figure 2 Location Specific Individual Risks of Fatality Contours for Persons Located Outdoors

ENVIRONMENTAL RESOURCES MANAGEMENT AIR PRODUCTS ACETYLENE PLANT MHI REPORT V2.0

V

Societal Risk

Societal Risk for the proposed Air Products Acetylene plant was calculated but the risk levels were so low that they did not appear on the FN Curve graph.

CONSEQUENCES

From a consequence perspective there are potential off-site effects from either

Acetone pool fires or Acetylene explosions, both resulting from a loss of

containment.

The following plot, Figure 3 shows the extent of an Acetone pool fire and it can

be seen that the 6.3 kW/m2 radiation level does not extend beyond the site

boundaries

Figure 4 shows that the worst case consequences, which are those posed by

loss of containment of Acetylene Gas, do however result in overpressure

generated by explosions extending some 82 metres beyond the proposed Air

Products Acetylene Plant site boundaries to the West, 70 metres beyond the

site boundaries to the North, 28 metres beyond the site boundaries to the East

and only a few metres beyond the site boundaries to the South for the final

double installation.

Figure 3 Area Enveloped by the Largest Acetone Pool Fire (D5)

37.5 kW/m2

12.5 kW/m2

6.3 kW/m2

Figure 4 Areas Enveloped by the Largest Explosion Scenario Phase 2 Double Generator Rupture

0.05 Bar

0.2 Bar

0.35 Bar

ENVIRONMENTAL RESOURCES MANAGEMENT AIR PRODUCTS ACETYLENE PLANT MHI REPORT V2.0

VIII

CONCLUSIONS

Due to potential incidents resulting in consequences extending beyond the proposed Air Products Acetylene Plant site boundaries from potential Acetlyene explosions, the site should be considered as a Major Hazard Installation in line with the current legislation. Environmental Resources Management Southern Africa (Pty) Ltd would declare the Air Products proposed Acetylene Plant located at Tilliet Road, Daleside near Meyerton in the Gauteng Province as a Major Hazard Installation (MHI) as outlined in the current legislation. As a result of being declared a MHI, the Requirements of the MHI Regulations must be followed completely to ensure the proposed Air Products Acetylene Plant is legally compliant. Copies of this risk assessment must be submitted to the Local Provincial Director of the Department of Labour, the Chief Inspector of the Department of Labour Head Office in Pretoria and the Local Authorities.

CONTENTS

1 INTRODUCTION 1

1.1 GENERAL INTRODUCTION 1

1.2 REQUIREMENTS OF THE MHI REGULATIONS 6

2 RISK ASSESSMENT & MANAGEMENT METHODOLOGY 7

2.1 DEFINITIONS 7

2.2 PROCESS OF RISK MANAGEMENT 7

2.3 HAZARD IDENTIFICATION 9

2.4 CONSEQUENCE ANALYSIS 9

2.4.1 Harm Criteria for Consequence Analysis 9

2.4.2 Consequence Modelling 9

2.5 FREQUENCY OF MAJOR ACCIDENT HAZARDS 11

2.6 RISK CALCULATION 12

2.7 RISK ASSESSMENT 13

3 POTENTIAL MAJOR HAZARDS 14

3.1 INTRODUCTION 14

3.2 HYDROCARBON POOL FIRES 14

3.3 FLASH FIRES 15

3.4 VAPOUR CLOUD EXPLOSIONS 15

3.5 ASPHYXIANT 16

4 ENVIRONMENTAL SITE SETTINGS 17

4.1 SITE LOCATION 17

4.2 METEOROLOGY 19

4.3 REQUIREMENTS OF OTHER ENVIRONMENTAL LEGISLATION 20

5 DESCRIPTION OF FACILITIES 21

5.1 DESCRIPTION OF SITE OPERATIONS 21

5.1.1 Bulk Storage Facilities 29

5.2 DESCRIPTION OF PRODUCTS STORED ON SITE 29

5.3 POPULATION DATA 30

6 APPROACH TO THE ASSESSMENT 31

6.1 TERMINOLOGY 31

6.2 HARM CRITERIA 31

6.2.1 Thermal Radiation 31

6.2.2 Explosion Overpressure 32

6.2.3 Flash Fire Flammability Limit 33

6.2.4 Fatality Probabilities 33

6.3 ASSESSMENT CRITERIA 37

6.3.1 Risk Tolerability Criteria for fatality approach 38

6.3.2 Individual Risk of Fatality Criteria 39

6.3.3 Societal Risk Criteria 40

6.4 METHODOLOGY 41

7 RISK ASSESSMENT 43

7.1 HAZARD IDENTIFICATION 43

7.1.1 Failure Scenarios 43

7.2 ESTIMATION OF CONSEQUENCES 47

7.2.1 Pool Fires 47

7.2.2 Asphyxiant Nitrogen Dispersion 50

7.2.3 Acetylene Explosion Modelling 50

7.3 ESTIMATION OF INCIDENTS 55

7.3.1 Frequency of Storage Vessels, Pipework and Cylinder Failures and also Off

Loading Road Tankers 55

7.4 RISK CALCULATION 58

7.4.1 Location Specific Individual Risk for the site Fatality Assessment 58

7.4.2 Societal Risk 61

7.5 ESCALATION EFFECTS 62

8 NEIGHBOURING MAJOR HAZARDOUS INSTALLATIONS 63

9 EMERGENCY PLANNING 64

9.1 MAJOR HAZARD INSTALLATION REGULATIONS, SECTION 6 - ON SITE EMERGENCY

PLAN 64

10 CONCLUSIONS 66

10.1 CONCLUSIONS 66

ANNEX A ERM CERTIFICATES OF ACCREDITATION

ANNEX B MHI REGULATIONS

ANNEX C MATERIAL SAFETY SHEETS

ANNEX D CONSEQUENCE AND FREQUENCY ANALYSIS

ANNEX E EMERGENCY RESPONSE PLAN STILL TO BE COMPILED BY AIR PRODUCTS

EN