It appears that the severity of the nuclear crisis at the Fukishima Daiichi nuclear plant that was triggered by an earthquake and giant tsunamis a month ago is far more serious than was originally envisaged. Japanese authorities who had originally put the crisis at a level 5 have raised the severity rating to 7, which is the worst rating on an international scale.

They have put the disaster on par with the 1986 Chernobyl nuclear crisis. The decision to upgrade the severity level was made after Japan’s nuclear safety body determined that at one point over the past month, the Fukushima plant was releasing 10,000 terabecquerels of iodine-131 for several hours; level 7 accidents are defined as releasing tens of thousands of terabecquerels.

The jump from level 5 to 7 is an alarming one as level 7 signifies a ‘major accident’ with ‘wider consequences’ than the previous level. It is likely to have substantial and long-lasting consequences for health and for the environment.

The reclassification to a higher level has raised fears that the situation in the plant has suddenly gotten worse. Experts have said this is not so. They claim that fuller assessment of available data has prompted the reclassification of the severity level.

While the severity of the Fukushima incident has been put on par with the Chernobyl crisis, experts say there are significant differences. In Chernobyl, the reactor core itself exploded, and fire fanned the release of radioactive material.

A very large amount of radioactive material was released over a very short span of time. Fukushima experienced a less critical hydrogen explosion. The volume of radioactive materials it released is believed to be about 10 per cent of that released by the Chernobyl reactor.

However, this does not mean that we can be complacent as the situation at Fukushima has not yet been brought under control. Radioactive material is still seeping out. So there is a possibility of the radiation here exceeding that from Chernobyl.

Anti-nuclear groups like Greenpeace rated the Fukushima crisis as a level 7 one almost three weeks ago, prompting many to question the government’s far slower response. Is the reassessment the result of an attempt to play-down the severity and a belated admission of the truth? The Japanese have suffered enough. Delayed information and cover-ups will stand in the way of efficient protection of the people from the impact of radiation.