1-Chloro-1,1-difluoroethane (R142b) can be used as the refrigerant, foaming agent and ORC (Organic Rankine Cycle) fluid. R142b was described as one of the interim substitutes in the Montreal Protocol (signed in 1987), and allowed to be used in developing countries until 2040. However the production and consumption of R142b were required to be frozen this year on the average data of 2009 and 2010 according to its latest amendment (signed in 2007). Binary alternatives R245fa/R142b, R227ea/R142b, R600a/R142b and R134a/R142b are possible substitutes in the initial transition period of frozen and phase-out R142b for the reason of pressure approach, which may be welcomed by the countries with wide use of R142b considering the technology and cost. This paper contributes to the flammability of these binary mixtures experimentally by using a self-made test rig built on the ground of Chinese National Standard. Not only the flammable limits of blends were studied, but also the related flame images were presented and analyzed. In addition, the flame suppression efficiencies of R245fa, R227ea and R134a have been compared and the lower flammable limits of R600a/R142b has been estimated and tested at different ratios. The presented work is beneficial to environmental protection. (C) 2013 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.