NR-20 was originally issued by MTb Ordinance No. 3.214 on June 8, 1978, under the title “Flammable and Combustible Liquids,” to regulate Clause II of Article 200 of the CLT, as revised by Law No. 6.514 on December 22, 1977.
Characterized as a Special Standard by SIT Ordinance No. 787 on November 29, 2018, NR-20 governs work involving flammables and combustibles, covering activities, installations, and equipment used across various sectors.
NR-20 has undergone six changes: four minor and two major revisions. The first major revision was approved at the 67th Ordinary Meeting of the Permanent Tripartite Commission (CTPP) on November 28-29, 2011, and published by SIT Ordinance No. 308 on February 29, 2012. This revision established the National Tripartite Thematic Commission (CNTT) for NR-20 to foster studies and discussions for legislative improvement.
The revised NR-20 focused on simplification, harmonization, and reducing bureaucracy without compromising safety and health at work.
NR-20 – Health and Safety at Work with Flammables and Combustibles
(MTP Ordinance No. 4219, December 20, 2022)
Annex I – Criteria for Worker Training and Program Content
Annex II – Exceptions to the application of item 20.4 (Classification of Installations)
Annex III – Flammable Liquid Tanks Inside Buildings
Annex IV – Occupational Exposure to Benzene at Automotive Fuel Retail Stations