Cybil Wilson has worked in one of Kerala’s big, shiny, brightly-lit sari shops for 10 years.

Her salary at the shop, in Trivandrum, has been consistently low but it is the pain and swelling in her legs that troubles her the most. Her employer forbids Wilson, and the other 120 female sales assistants working across the four floors, from sitting down during a 12-14 hour shift.

“We can’t use the lifts either. All customers pay on the ground floor for their purchases and we have to accompany them so we are up and down the stairs all day. A few times, when we did use the lift, customers complained about having to share it with us,” said Wilson.

Now the Kerala government has announced it will amend its labour laws to include a clause obliging employers to let women sit – the result of a fight by a women’s union for “irippu samara” (the right to sit in Malayalam) for these unrepresented shop workers.

Most owners of sari shops and other retail outlets forbid women, the bulk of the shop workforce, to sit. Even leaning against a wall can be punished. Lunch is 30 minutes. Toilet breaks are strictly limited. Talking to colleagues can lead to salary deductions. Employers monitor CCTV footage to check for compliance.

The women’s union, called Amtu, was set up by Viji Penkoot, the leader of a women’s collective, Penkootu, when the male-dominated unions in the state ignored the issue.

She began agitating for the right to sit eight years ago, when a sales assistant in Kozhikode who leaned against a wall while a customer pondered which sari to buy, had her pay cut by 100 rupees (£1) for the “offence”.

“The women are careful not to drink too much because they cannot go to the toilet when they want to. They get urinary infections, kidney problems. They have varicose veins and joint pain from standing. It took us a long time for the government to pay any attention to this problem,” said Penkoot.

On 4 July, the Kerala state cabinet, reacting to street protests by shop assistants, announced it would amend the existing law, which fails to specify which amenities should be provided to sales assistants, to include the right to sit. “It’s our policy to protect the interests of all our women workers and this gap in the law had to be plugged,” said Thozil Bhawan, a labour commissioner.

The new law will stipulate a minimum monthly starting salary of 10,000 rupees (£110), an eight-hour day, a chair or stool, an afternoon tea break, and a lunch break, with a duration yet to be decided by the Kerala cabinet, be provided.