The lower house of the Japanese parliament on Tuesday passed a bill that, if passed, will allow the country to formally accept foreign blue-collar workers and give them a pathway to permanent residency, an initiative some see as a step toward becoming a nation that welcomes immigrants.

In recent years, Japan has already seen a sharp increase in the number of foreign workers, ranging from professionals to unskilled ethnic Japanese mostly from Brazil. Here are five key points of the new legislation.

Doesn't Japan already accept foreign blue-collar workers?

Japan has received unskilled foreign workers since 1993, but only as trainees, who are required to stay with one employer and are typically allowed to stay for only three years. The new bill will accept them as regular workers who would be free to choose their employer. But jobs are limited to 14 industries, including construction, elderly care and agriculture, and the applicants need to demonstrate requisite technical skills and a good command of Japanese. The main target of the program is those who have completed the existing trainee program.

How long could blue-collar workers stay in Japan?

They will be allowed to work freely for up to five years, but there is one restriction: the visa is given only to the workers and not to their families.

The government expects to receive applications from up to 345,150 people over the next five years -- many of them from those who are already in Japan. This will be on top of those people Japan will continue to accept as trainees. Japan accepted some 480,000 new trainees between 2013-2017.

The hurdle to permanent residency remains high, however. The government continues to view the trainee and blue-collar worker program as a way to transfer skills to developing countries, with the idea that those who have completed the programs should eventually return home. Applicants for permanent residency must be able to show they have had an unbroken 10-year stay in Japan.

Blue-collar workers who have mastered the required skills can apply for a higher status visa, which is renewable indefinitely and allows them to bring their families.

What is the application process for the new worker visa?

The standard route to get a worker visa would be to first complete the traineeship and then apply for a worker visa through the employer.

No details have been released about independent applicants or those who want to register with a job placement agency.

Why is Japan keen on accepting foreign workers?

Japan Inc. is facing a serious worker shortage. The unemployment rate is just above 2%, the lowest since early 1990s. The widespread labor shortage is underscored by the fact that there are more jobs available than the number of job seekers in every prefecture of the country -- the first time that the country has faced such a situation.

The bill has also been prompted by a growing desire among employers to keep foreign trainees rather than sending them home when their apprenticeship ends. Businesses face closer scrutiny of the work conditions of their foreign workers and are obliged to treat them fairly. Increasingly, employers want productive workers who are worth their salary.

What is the outlook for the bill's passage?

Abe's ruling coalition is aiming to get the bill enacted next month and bring it into effect in April. With a majority in both houses of parliament, the coalition can ultimately steamroll the proposal, if necessary, says Hisashi Yamada, a labor expert at the Japan Research Institute.

The opposition argues that the government is trying to accept immigration through the back door and voices concern that there is not yet the schools and health care infrastructure in place to accommodate immigrants and their families. Such arguments could sway public sentiment and make it difficult for the ruling camp to push the bill through.

To allay concern among conservative lawmakers of the legislation sparking an influx of foreign workers, the ruling camp has revised an element of the bill, promising to undertake a review two years after the law comes into force, instead of after three years.

Even critics, however, acknowledge the country's need for foreign workers. The main debate is expected to focus on whether the government can ensure that foreign workers will be able to work under proper conditions and will be integrated into the host communities.