Bangkok's 26 areas declared "nuisance problem control areas" Wednesday

The Pollution Control Department on Wednesday morning reported unsafe levels of PM2.5 – airborne particulates 2.5 microns or less in diameter – in 39 locales in and around the city, of which 23 were along main roads. 

The level hit 141 micrograms of PM2.5 per cubic metre of air – nearly three times the safe limit of 50 – on Rama II Road in Muang Samut Sakhon. 

The situation was unlikely to improve in the afternoon and PM2.5 levels would remain high until February 4, it said.

The National Environment Board will meet on February 4 to consider lowering the safe limit from 50 to 35 for the next three to five years and then to 25 as recommended by the World Health Organisation in next 10 to 20 years. 

Governor Aswin said all related agencies and schools would be informed of “nuisance problem control area” designations so they can consider measures appropriate for each area. 

He said a centre to provide twice-daily updates on air pollution would be established.

A source at the Bangkok Metropolitan Administration said 26 districts with 76-100 micrograms of PM2.5 and some with 51-75 micrograms would be designated.

They include Sathorn, Bang Khen especially the front of Kasetsart University, Bang Khun Thien especially on Intharaphithak Road, Ratchathewee, Samphanthawong, Phayathai, Wang Thong Lang, Pathumwan, Bang Rak, Bang Kho Laem, Yannawa, Chatuchak, Bang Kapi, Lat Krabang, Thon Buri, Klong San, Bangkok Noi, Phasi Charoen, Bang Phlat, Phra Nakhon, Klong Toei, Bang Sue, Lak Si, Bung Kum, Bang Na and Din Daeng.

Rama II Road in Samut Sakhon could also be on the list. Natural Resources and Environment Minister General Surasak Karnjanarat said the governor of that adjacent province where air pollution has been severe for several consecutive days was authorised to declare nuisance problem control areas. 

The measures they trigger chiefly target diesel-engine exhaust, outdoor burning and construction activities.

The BMA source said Aswin would discuss dust control at construction sites with the BMA Department of Public Works, Mass Rapid Transit Authority and other agencies. 

Failure to abide by control-zone regulations could result in three months’ imprisonment and/or a fine of up to Bt25,000.

The authorities might also consider installing air-quality measuring devices at tollgates for diesel-engine cargo trucks and press motorists using the expressways to use the automatic M-Pass toll system to reduce traffic congestion at the gates, the source said. 

The Highway Department spent Tuesday evening spraying water from high-pressure hoses at the Thap Chang 1 tollgate on Highway 9 in the Bang Phli-bound lane and at the Tap Chang 2 tollgate where traffic heads towards Bang Pa-in in Ayutthaya. 

It was not known at press time whether the 20-micron water spray, fine enough that it would not affect driver visibility or cause flooding, was found to reduce pollution.