Metro Manila (CNN Philippines) — The Executive Order (EO) on the no-smoking policy in public places is sitting on President Rodrigo Duterte's desk, awaiting his signature.

But why does the country need an Executive Order for a public smoking ban?

There's already a law in the Philippines banning smoking in public places — Republic Act 9211 or The Tobacco Regulation Act of 2003 — and the Philippines has been a signatory to a tobacco control treaty for more than a decade.

According to lawyer Jim Asturias of Health Justice Philippines — an NGO focusing on overlapping issues of health and law, and public health policy —the Executive Order is necessary to address certain gray areas, including the definition of "public places" and the kinds of tobacco products that will be banned.

"If the President will indeed follow Davao ordinance it will also cover shishas, electronic device systems, e-cigarettes," he said.

EO empowers LGUs

Department of Health Secretary Paulyn Ubial said the executive order was patterned after Davao City's anti-smoking ordinance, which was implemented when Duterte was still the mayor of the city.

According to Ubial, once Duterte signs the executive order, local government units should outline penalties for violators.

"It's an EO so it's just directive for all national and local to implement it. But finer guidelines and sanctions will be in local ordinances," she said.

Once the President signs the EO, smoking cigarettes, tobacco, shisha (waterpipe), e-cigarettes, or similar devices will be prohibited in public places, including in public vehicles, nationwide.

Smoking will be prohibited in all public outdoor spaces, enclosed and partially enclosed public spaces, accommodation and entertainment establishments, and work places.

The no-smoking policy will also cover drivers, conductors, and passengers of public utility vehicles.

Ubial said designated smoking areas will be allowed in places where the public will not be exposed to second-hand smoke.

The smoking areas will have highly visible signage — alongside a graphic depiction of the negative effects of smoking to one's health and also to those inhaling the second hand smoke.

"Designate a smoking area away from the public. At the back of a hotel, at the parking area," Ubial said on Tuesday.

Ubial hopes Duterte signs the EO before the month ends, or before the full implementation of the graphic health warning law this November

Davao City's smoking ban has been recognized by the World Health Organization as an effective smoke-free order in an urban setting. WHO noted that Davao's smoking policy "demonstrates that smoke-free laws can work in the Philippines."

CNN Philippines' correspondent Pia Bonalos, digital producer Lara Tan contributed to this report.