How to control Air Pollution

How to Control Air Pollution from Food and Beverage industries in Myanmar?

Source – SUSTENT Consulting Pvt. Ltd

Air inside the food and beverage enterprises comprises of suspended dust particles, gaseous fumes from fuel combustion and microorganisms. The presence of such unhygienic air not also impacts health of the workers but also cause food contamination. Hence, it is necessary to take measure to minimise the impact of indoor air pollution. The section below will discuss about the measures to be taken to control the air pollution in food and beverage enterprises.

Establishing Policy for Air Pollution Control

The management of an enterprise can display their commitment towards air quality management by establishing an air quality policy statement, which may be part of the environment policy or as a stand-alone air pollution control policy. This policy must align with the purpose of the organization. It must contain a framework for establishing air quality management objectives and targets. The policy must be reviewed/ updated after the monitoring. Things you should consider while developing an policy are:

• The policy must be in context of your organization and must convey a sense of direction and principles for implementing actions
• It must help to fulfil legal and regulatory requirements and contractual obligations
• It must convey the organization’s commitment to continued improvement in air quality for better health of workers
• It must display the management’s commitment to ensure the availability of the information and resources necessary to achieve objectives and targets

The organization management must ensure that the policy is available as a document accessible to all the employees of the enterprise and must put in effort to communicate the policy to persons at all levels of the organization so that they understand it, implement it and sustain the improvements.

 

5.5 Awareness/Sensitization Session on Air Quality Management-Board of Directors, Manager, staff

• Use posters and pamphlets highlighting the air pollution problems in Myanmar to sensitize the staff how bigger the problem is
• Newsletters are good tools – for letting colleagues know that air pollution is an important item on the enterprise agenda.
• Encourage staff to practice hygiene while working. Provide them with personal protective equipment’s to minimize the health impacts due to air pollution
• Sensitize staff regarding proper use of PPEs, if needed, to reduce their exposure to air contaminants in enterprise.
• Engage your staff in problem-solving methods to reduce air pollution within the enterprise.
• Imparting trainings to workers on health, safety, hygiene, and food safety every 1-3 months.
• Practise what you preach- the management and other people at leadership positions should themselves take adequate measures to minimise air pollution and then expect their staff to do same efforts.

 

5.6 Identifying the Sources of Air Emissions From Food and Beverage Industries

The major indoor sources of air pollution in food and beverage industries include:

• Fuel-burning combustion appliances. Further use of charcoal, wood, crop waste for cooking activities further aggravates level of PM in surrounding.
• Tobacco Smoke
• Building materials and furnishings as diverse as:
  • Deteriorated asbestos-containing insulation
  • Newly installed flooring, upholstery, or carpet
  • Cabinetry or furniture made of certain pressed wood products
• Products for household cleaning and maintenance containing bleach or chloramines are also known to cause respiratory issues and allergic reaction via inhalation and absorption through skin
• Inadequate ventilation (exhausting contaminated air and inletting fresh air)
• Emissions from vents from storage and handling operations, e.g., transfers, the loading and unloading of products, raw materials. The storage may affect the impact on ambient air quality too and may impact human & ecological health due to a temporary increase in the level of PM and other gases.
• Furthermore, inefficient Heating Ventilation and Air Conditioning (HVAC) system aggravate the level of indoor dust pollutants making difficult for the workers to work inside industries.
• Waste gases releasing from emission control equipment, such as filters, thermal oxidizers or adsorbers if installed in industries
• Release of gases from leaks and valves

As identified in many literatures, Grilling, frying, and toasting of food are known to elevate the indoor air particle concentration⁸. Use of stoves, ovens, boilers, microwaves, and other combustible appliances for cooking are the major sources of release of indoor air contaminants.  Some of the examples include:

Baking Process: As a result of using ovens operated by Diesel or fuel wood, air emissions are observed which include NOx, PM and VOCs. The major air emissions of concern from bakery unit are volatile organic compounds (VOCs). The primary VOC emitted from bakery operations is ethanol. It is produced by yeast metabolism during fermentation and is emitted in large amounts when the dough is exposed to elevated temperatures in the oven.

Snacks manufacturing units generates fumes during the frying process which may contain suspended water & oil droplet mix.

Table 3: Release of PM concentration from different cooking practices⁹

Cooking practices	Release of PM2.5 (µg/m3)
Frying	1.54 × 105
Grilling	1.61 × 105
Kettle	1.56 × 104
Microwave	1.63 × 104
Oven	6.15 × 104
Toast	1.14 × 105

⁹He, C., Morawska, L., Hitchins, J. and Gilbert, D., 2004. Contribution from indoor sources to particle number and mass concentrations in residential houses. Atmospheric environment, 38(21), pp.3405-3415.

 

5.7 Air Quality Monitoring Methods

For monitoring indoor dust:

The conventional techniques used for monitoring dust particles is Gravimetric analyses.

• Gravimetric analysis is the process of isolating and weighing an element or a definite compound of the element in as pure a form as possible.
• It involves use of sampling pumps, conditioning and weighing of filters, recording sampling conditions and taking an account of sources of errors
• High volume sampler with size selective inlet for PM is used to draw the air sample.
• The mass is determined by subtracting the mass of post weighed filters from pre weighed filters.
• It is mostly done using the Teflon-membrane filter, as it is the most stable, durable in comparison to other filters.
• Gravimetric analyses have been widely used in various studies for collection, measurement and for analysing composition of indoor PM¹⁰.

Figure 7: Steps to perform Indoor Dust Sampling using Gravimetric Analysis

Emissions from food processing activities are principally associated with matter and odour. Particulate matter PM₁₀ emissions should typically not exceed 50 mg/Nm³.

¹⁰Varshney, P., Saini, R. and Taneja, A., 2016. Trace element concentration in fine particulate matter (PM_2.5) and their bioavailability in different microenvironments in Agra, India: a case study. Environmental geochemistry and health, 38(2), pp.593-605.

For VOCs monitoring

VOCs are released as residues and emission which are a result from fermentation process, cooking, clean-up, disinfection, and other steps in food production. The problems associated with VOC in food and beverage production include:

• Toxicity,
• Odours, and
• Photoreactive compounds due to photochemical reactions

A commonly used, proven method that rapidly detects a wide range of VOC over the concentrations of interest is photoionization detection (PID). Direct reading devices such as air quality detectors and sensors which are well calibrated can also be used to detect VOCs using this method.

For CO monitoring

• It is essential to monitor inside the places where combustion activities are common.
• The measurement should be done at each space near combustion devices while they are in use
• At least one continuous monitoring location per floor only if the combustion activity is going on.
• The measurement can be done at the outdoor air intake (window and air vents) to the building as well to check if the sources are not too close to the roadways
• The sample can be taken by using adsorption tube with subsequent chemical analyses of the tube. Accurate results are obtained by using certified tube and direct reading devices which are well calibrated may also be used.

Stack Emission Monitoring for the Emissions Discharging Directly to Atmosphere

Stack Monitoring is a procedure for evaluating the characteristics of the emissions from industrial waste gas streams discharged into the atmosphere. It is a point source emission. In food and beverage enterprises, it is used to monitor the pollutant from DG stacks, waste handling, chimneys, and related activities. The stack monitoring is done with the help of Gas Analysers which are installed at the exhaust point.

Note: An accredited qualified air quality personnel is required for carrying out air quality monitoring in the facility.

 

5.8 Compliance Check Against Applicable Legal Requirements

Indoor Quality Standards

Table 4: Indoor CO and CO₂ Monitoring Standards

Pollutant Type	Occupational Safety and Health Standard (OSHA)	World Health Organisation (WHO) Standard
CO	55 mg/m3 (8 Hour average)	7 mg/m3 (24 Hour mean)
CO2	9000 mg/m³ (8 Hour average)	–

Source: Occupational Safety and Health Administration. United States Department of Labour www.osha.gov

Table 5: Indoor VOCs and PM Monitoring

Pollutant Type	WHO Standard
VOCs
Formaldehyde	0.1 mg/m3 (30 minutes)
Naphthalene	0.1 mg/m3 (30 minutes)
PM
PM2.5	25 µg/m3 (24-hour mean)
PM10	50 µg/m3 (24-hour mean)

Source: WHO Air quality guidelines for particulate matter, ozone, nitrogen dioxide and sulphur dioxide.2005.

 

Emissions from food processing activities are principally associated with matter and odour. Particulate matter PM10 emissions should typically not exceed 50 mg/Nm³.

Stack Emission Monitoring Standards

Table 6: Stack emission standards as given by Central Pollution Control Board of India (CPCB) for Boilers and DG sets:

Stack Monitoring Parameters for Boilers and DG Sets	Stack Monitoring Limits (mg/Nm3)
Particulate Matter (PM)	150
Sulphur Dioxide (SO2)	40
Oxides of Nitrogen (NOx)	25

Source: Stack Emission Monitoring & Stack Emission Testing

 

5.9 Mitigation Measures to control air pollution

Simple measures to reduce indoor air pollution in your enterprise.

• Do not use unprocessed coal and kerosene as fuel
• Well ventilate kitchen spaces
• Stop smoking tobacco
• Reduce burning incense inside the enterprise.

Mitigation measures to be taken by Management and Board of Directors

• Provide healthy work environment to your employees
• Ensure regular maintenance of Heating Ventilation and Air Conditioning (HVAC) system of the facility
• Regular surveillance of the staff showing health related issues.
• Water Sprinkling to be done at least once a day outside the facility to suppress the release of airborne particles from transportation of raw material
• Transport vehicles, as well as transport routes, should be properly maintained to minimize smoke/dust emission from vehicle exhausts and unpaved roads.
• Keep indoor plants inside the facility like Areca Palam, Money plant to increase oxygen level in the surrounding.

Measures to be taken by staff to minimize the effect.

• Wear well-fitted face masks specially when engaged in cooking.
• Stay hydrated all the time
• Eat jaggery after food to clear off harmful pollutants as it is natural cleansing agent for lungs
• Practice hygiene. Maintain at least 1 metre distance from yourself and anyone while sneezing and coughing
• Always important – consult a health professional, or visit a health facility, if you experience any adverse effect which may arise from air pollution.

Measures to combat indoor air pollution using equipment

Exhaust Fans

• Install and use exhaust fans vented to the outside when cooking
• All the units equipped with boiler should ensure that pollution control device (like multi cyclone /bag filters / wet scrubbers) is installed in boiler.
• Provision for adequate exhaust fan and ventilation systems to be provided in process area.
• Open burning of organic fuel like cow-dung cake, husk, wood etc. (used in earthen oven in various sectors) should be avoided and burner operated by cleaner fuel like Compressed Natural Gas or electricity should be introduced.

Air filters to improve air quality in food industries

• Installation of air filters should be in a way that keep air conditioning and ventilation system remain free of suspended particles.
• Use filters that keep air purity intact and has ability to differentiate between dust and gaseous particles.
• it is recommended to always use certified filters of the highest purity.

Industrial Fans for managing humidity and condensation

The continuous washing processes as well as the presence of products that can elevate humidity into the environment make controlling humidity control difficult task in food and beverage enterprises. On contrary, condensation can lead to safety problems, causing slips and accidents among operators by accumulating on the ground. Hence, it is recommended to use High Volume Low speed (HVLS) industrial fans which allow a greater amount of air to circulate in the work environment, which improves the evaporation of possible dew points, thus contributing to improve air quality in food industries that suffer from this problem.

Table 7: Tabular matrix showing air quality management system for implementation in F&B industries

Source	Emission	Mitigation Measure
Storage and handling of raw material and food products	·         PM2.5 and PM10 ·         During product storage & the packing, odour will be generated which could affect mood, anxiety, and stress level.	·         Good Ventilation ·         Training to workers on proper handling of Material ·         Cover skips and vessels, and stockpiles, especially outdoors. ·         Enclose silos and containers used for bulk storage of powders and fine materials ·         Good housekeeping ·         Dust Collection systems
Food processing methods like heating, roasting, grilling, baking, canning, fermentation, or hydrolysis	·         PAHs, VOCs (especially during fermentation using yeast), Odour, PM due to Combustion activities	·         Efficient HVAC System ·         Use of Ceiling and Exhaust Fan ·         Use of Air Filters ·         Open burning of organic fuel like cow-dung cake, husk, wood etc. (used in earthen oven in various sectors) should be avoided and burner operated by cleaner fuel like Compressed Natural Gas or electricity should be introduced. ·         Use of PPE for workers (e.g., face masks, mouth and nose cover, gas masks)
During the transportation of food products	·         PM, SO2, NOx	·         Vehicles with valid Pollution Under Control (PUC) Certificate. ·         Dust suppression on haul roads ·         Water Sprinkling once a day ·         Avoid overloading heavy truck ·         Green belt development
DG Stack Emission	·         PM, SO2, NOX, CO	·         The DG sets should have valid Pollution Under Control Certificate (PUC) ·         The exhaust pipe/stack should open to external environment and adequate height of stack should be maintained so that it’s emission doesn’t disturb the nearby surrounding
Refrigeration	·         Fugitive Emissions	·         Operate facilities under partial vacuum to prevent fugitive odour emission. ·         Regular inspection of chilling and freezing equipment to monitor loss of refrigerants
Exhaust from Oven, Boilers and chimneys	·         Fugitive emissions ·         CO, CO2, NO2, SO2, PAHs	·         Have a trained professional inspect, clean and tune-up central heating system (furnace, flues and chimneys) annually. Repair any leaks properly.
Microbial Contamination	·         Dust, Parasites, Bacteria, Yeasts, Moulds and viruses	·         Good Hygiene & Sanitation facility ·         Regulate temperature and maintain humidity ·         Chemical Disinfectants ·         UV Irradiation method ·         Fogging

 

5.10 Continuous Monitoring To Improve Air Quality (Indoor And Outdoor)

Monitoring becomes essential to ensure that the mitigation measures planned for environmental protection function effectively during the entire period. It will also allow for validation of the assumption and assessments made in the present study. The frequency of the monitoring should be once every three months round the year for all the pollutants as discussed in section 5.8.

 

5.11 Case Studies

Case Study-I

Before: In a food and beverage enterprise, occupants started complaining of headache, nausea, and drowsiness. On inspection, a flue from chimney was observed to blocked by soot particles.

After: The chimney was immediately cleaned up and personnel was appointed for regular check and maintenance. A CO₂ monitor was set up to measure the level of CO₂ to trigger an alarm after crossing OSHA threshold value. Immediate requisite steps are also taken to minimise the air pollution impact on health of workers such as:

• Changes in the time shift of workers to avoid overcrowding
• Advisory to use Personal Protective Equipment (PPE) when needed to reduce their exposure to CO2 and air contaminants
• Provision for adequate number of exhaust fans and ventilation systems in the facility

Key Impacts:

• Increase in Working efficiency of staff
• Improved ventilation system
• Reduced absenteeism due to health-related issues

Case Study-II

Paharpur Business Centre (PBC) Case Study

In India, Paharpur Business Centre (PBC) has been rated as one of the healthiest office buildings in Delhi region by Central Pollution Control Board (CPCB) and Chittaranjan National Cancer Institute (CNCI) because PBC grows its own fresh air with the help of over 1200 air purifying plants¹¹. These plants not only detoxify indoor air but also enriched with oxygen.

Few indoor plants that they have utilized for air purification include¹²:

Areca Palm (Chrysalidocarpus lutescens): Removes Chemical Toxins Produces O₂ During the Day

Snake Plant (Sansevieria trifasciata): Removes Chemical Toxins Produces O₂ at Night

Money Plant (Epipremnum aureum): Removes Chemical Toxins & Produces O₂ During the Day

Figure 8: Indoor Plants

Source: Open Source

 

Key Highlights of the study

• Blood Pressure levels of the building occupants was improved
• Absenteeism was reduced
• Bacteria and Fungus level was significantly reduced
• On the top of the sixth floor is a self-created greenhouse that helps circulate fresh air after removing formaldehyde, benzene, bacteria and carbon monoxide from ambient air and pumping it into the air-conditioning system

¹¹Paharpur Business Centre.

¹²Grihaindia.