Contents
20.1 Introduction
20.2 Scope of Application
20.3 Definitions
20.4 Installation Classification
20.5 Installation Design
20.6 Installation Dossier
20.7 Risk Analysis
20.8 Construction and Erection Safety
20.9 Operational Safety
20.10 Installation Maintenance and Inspection
20.11 Workplace Occupational Safety and Health Inspection
20.12 Worker Training
20.13 Ignition Source Control
20.14 Prevention and Control of Leakage, Spillage, Fire, Explosion and Fugitive Emissions
20.15 Installation Emergency Response Plan
20.16 Incident Notification
20.17 Employer and Contractors
Annex I Worker Training Criteria and Syllabus Content
Annex II Exemptions from Clause 20.4 Installation Classification
Annex III Indoor Flammable Liquid Storage Tanks
Annex IV Occupational Benzene Exposure at Motor Fuel Retail Service Stations
Glossary
20.1 Introduction
20.1.1 This Regulatory Standard sets minimum requirements for occupational safety and health management to prevent accident risks arising from the extraction, production, storage, transfer, handling and manipulation of flammable and combustible liquids.
20.1.2 This standard and its annexes shall be applied to prevent and control risks in work involving flammable and combustible substances. The provisions of NR 15 Unhealthy Activities and Operations and NR 16 Hazardous Activities and Operations shall be adopted for identifying unhealthy or dangerous working activities and operations.
20.2 Scope of Application
20.2.1 This standard applies to the following activities:
a) Extraction, production, storage, transfer and handling of flammable substances during design, construction, erection, operation, maintenance, inspection and decommissioning of installations;
b) Extraction, production, storage, transfer and handling of combustible liquids during design, construction, erection, operation, maintenance, inspection and decommissioning of installations.
20.2.2 This standard shall not apply to:
a) Offshore oil and gas exploration and production platforms and supporting installations as specified in Regulatory Standard 37;
b) Single-family residential buildings.
20.3 Definitions
20.3.1 Flammable liquids: liquids with flash point ≤ 60 degrees Celsius.
20.3.1.1 Liquids with flash point higher than 60 degrees Celsius shall be treated as flammable liquids when stored and transferred at temperatures equal to or above their flash points.
20.3.2 Flammable gases: gases capable of burning when mixed with air at 20 degrees Celsius and standard pressure of 101.3 kPa.
20.3.3 Combustible liquids: liquids with flash point greater than 60 degrees Celsius and not exceeding 93 degrees Celsius.
Table 1
|
Class I |
|
a) Regarding activity: |
|
a.1 Service stations with flammable and/or combustible liquids |
|
a.2 Piped distribution of flammable gases with MAWP limited to 18.0 kgf/cm² |
|
b) Regarding permanent and temporary storage capacity: |
|
b.1 Flammable gases: over 2 tons up to 60 tons |
|
b.2 Flammable/combustible liquids: over 10 m³ up to 5000 m³ |
|
Class II |
|
a) Regarding activity: |
|
a.1 Flammable gas bottling plants |
|
a.2 Pipeline transportation of flammable and combustible substances |
|
a.3 Piped gas distribution with MAWP over 18.0 kgf/cm² |
|
b) Regarding permanent and temporary storage capacity: |
|
b.1 Flammable gases: over 60 tons up to 600 tons |
|
b.2 Flammable/combustible liquids: over 5000 m³ up to 50000 m³ |
|
Class III |
|
a) Regarding activity: |
|
a.1 Refineries |
|
a.2 Natural gas processing units |
|
a.3 Petrochemical facilities |
|
a.4 Ethanol manufacturing plants |
|
b) Regarding permanent and temporary storage capacity: |
|
b.1 Flammable gases: over 600 tons |
|
b.2 Flammable/combustible liquids: over 50000 m³ |
20.4.1.1 For classification criteria, the type of activity shall take precedence over storage capacity.
20.4.1.1.1 The activity type shall not prevail over storage capacity when the capacity exceeds 250,000 cubic meters of flammable and/or combustible liquids or 3,000 tons of flammable gases.
20.4.1.2 Where an installation falls into two different classes due to storing both flammable liquids/combustible liquids and flammable gases, the higher class shall be adopted.
20.4.2 Annex II sets forth exemptions for the application of Table 1 — Installation Classification.
NR-20 - Occupational Safety and Health for Work with Flammable and Combustible Substances
