Many of those volunteers angrily dispute the notion they were a burden. They insist that in many instances they were able to deliver respirators, hard hats, and protective boots to workers when no one else seemed able.
Ground zero volunteer Rhonda Shearer and her daughter launched a fast-moving supply system that bypassed regular channels, often infuriating city officials.
Even as she delivered box trucks packed with supplies over months of recovery work, she increasingly ended up in a cat-and-mouse game with New York City's police and emergency management agency.
Shearer, 53, said the experience convinced that agencies are ill-equipped to handle major disasters — but don't want outsiders pointing out their failings.
Similar frustrations arose after Katrina, when people were shocked that the government struggled to take basic supplies such as water to the worst areas.
''They're more worried about keeping volunteers out than doing an analysis of what really went wrong,'' said Shearer. ''Independent citizens need to be involved, where we have no ax to grind or cross to bear. But we will tell the truth, and we will tell what we see and bear witness to the incompetence.''
Dickinson, the federal fire official, said the government is not trying to discourage volunteers, but he thinks there should come a time, within a few days of a disaster, when civilians step back and let the professionals take control.
Supporters say the ID cards could be checked at a disaster area with a card-reader device and used to verify a person's unique skills. For example, if police officers have been trained to handle hazardous materials, officials at the scene could deploy them to an area where their skills would be best put to use.
For reasons ranging from general safety to protection from lawsuits, construction and demolition companies want to see a disaster ID card program succeed.
Mike Taylor, executive director of the National Demolition Association, said his industry is talking with aides to Gov. Arnold Schwarzenegger about putting it in place in his state.
''If California goes ahead and does that, it will flow across the country. This is a really smart idea by someone in the Bush administration to be able to control access to the site and frankly, make sure there are no untrained people,'' said Taylor. ''If somebody goes running down to the site, you have to stop and ask them, wait, are they certified to do this work?''