Toyota team president John Howett reckons the planned introduction of KERS to Formula One next season lies in the balance.
The spotlight is back on Kinetic Energy Recovery Systems after a BMW Sauber mechanic suffered an electric shock on Tuesday after coming into contact with a car that was fitted with the device during testing in Spain.
This comes just a week after the Red Bull factory at Milton Keynes was evacuated after a battery system test of their KERS system went wrong.
Howett has expressed the opinion that the planned 2009 introduction of the system, which stores heat energy dissipated from a car as an additional power source, has left teams struggling to meet their deadline.
"The challenges are enormous for everybody," Howett told autosport.com.
"We're all fighting very hard to have a raceable, safe KERS, but whether it is achievable or not has to be seen.
"I think if you read between the lines of a lot of teams I think a lot of people are struggling."
Honda team principal Ross Brawn is another one who is unsure as to whether KERS will be used once the season gets underway next year.
"I don't know for certain," Brawn told autosport.com. "We will if it's a performance gain, and we haven't done enough work yet to know if it's a performance gain. We are scheduling to start the season with it, but we will see how it develops.
"It's rather too early to say, but the new car is designed to accommodate it and the day that it becomes a positive, net performance gain we will start to race it."

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