Chapter 17: Waste Minimization

Effective Date: July 1, 1997 (Issue No. 2)

Last Updated: September, 2023

A. Introduction

The concept of waste minimization "4R" widely adopted at HKUST refers to reduce, reuse, recycle and replace. Waste minimization goals at HKUST are to optimize waste reduction and encourage recycling activities on the campus. These activities are basic to most waste management programs. Effective source reduction and recycling requires strong administrative leadership. Furthermore it requires the cooperation of university operations, faculty and students to develop comprehensive waste reduction and recycling programs that effectively divert solid and liquid waste from disposal.

Source reduction - the reduction of waste at or near the source of generation and reuse are considered among the most promising options for diverting the growing volume of waste in industrialized societies. The rationale is simple: The less waste generated, the less there is to dispose. For example, avoid using disposable items in catering outlets and use environmentally friendly bags instead of plastic bags in supermarket to reduce waste. When waste generation is reduced or materials are reused, less money and time need to be invested in other more complicated waste management options. In addition, reducing the volume of hazardous waste reduces the level of hazard to all personnel. Generally speaking, reduction and reuse are cost-saving, resource-conserving, environmentally sound alternatives to traditional forms of waste management (e.g. landfill disposal). That’s why they are usually ranked at the top of the hierarchy of preferred waste management strategies, even higher than recycling.

As with any large institution, the opportunities to reduce waste or to reuse materials at colleges and universities are practically limitless. They can be found anywhere waste materials are generated on campus: in offices, classrooms, workshops, laboratories, printing facilities, libraries, mail rooms, campus stores, student unions, food service areas, and dormitories. Source reduction and reuse also usually require significant behavioral or operational changes.


B. Responsibilities

It is everyone's responsibility to minimize the amount of waste produced in the campus university.  Departmental management is encouraged to monitor the volume of chemicals consumed and to develop a plan to reduce hazardous waste. It follows logically that a leading university in the engineering and science fields would also lead in modern approaches to waste minimization. HSEO will provide advice on reducing consumption at any level from individual chemicals up to a system approach. Consumption and disposal patterns for other non-hazardous waste producing activities should be evaluated with a mind to reducing waste as well.


C. Approaches

Waste minimization has been defined as “anything that reduces the load on (hazardous) waste storage, treatment or disposal facilities.” Waste reduction is usually only accomplished by “in-plant changes.” In a large academic institution like HKUST, “in-plant changes” means that operations or experiment planning must include action designed to minimize the use of chemicals, materials or resources necessary to accomplish the specific goals of the person or organization.

To summarize:

1)planning for research done by faculty members and assistants

2)planning for the conduct of teaching laboratories, and

3)planning for procurement of chemicals, products and materials for use within and around the physical plant of the University by CLS or other organizations

In general, the active teaching, research or operational organizations in the University which use chemicals or chemical products can positively affect waste minimization goals in the following ways:

Change Materials Purchasing and Control Methods

Frequently, raw materials and supplies are bought based on minimizing purchase cost without considering the disposal cost. To minimize disposal of new or unused material:

  • reduce to a minimum the number of different products (e.g., cleaning solutions, lubricating fluids, etc) used by service organizations. This streamlining mitigates shelf-life problems and reduces the number of partially used containers which need to be disposed of.
  • Buy in container sizes appropriate to the actual use. It can be less expensive to buy liter containers of a perishable product than to purchase gallons or more of the product at a lower initial unit cost and then later have to dispose of the unused portion.
  • Reduce the inventory of hazardous materials to a minimum, and ensure that old containers are rotated from the back of shelves to the front when new material is purchased. This effort will reduce the waste of unused materials due to the expiry of their shelf-life.
  • Locate other consumers for expired or soon-to-be-expired chemicals. Within large research institutions like HKUST, one person’s waste can be a useful reagent for another scientist. The condition of many chemicals does not change during long term storage, particularly within amber glass bottles. Before a chemical is discarded as waste, the responsible person should check with CLS, HSEO or other faculty to locate a consumer for the reagent. This practice will greatly reduce the overall cost of hazardous waste disposal to HKUST, and within Hong Kong tertiary institutions.

All of the above measures will reduce the cost of raw materials and waste disposal, as well as the investment tied up in working capital inventory.

Improve Housekeeping Practices

Within plant service functions, good housekeeping practices include careful estimation of required usage of chemicals such as detergents, paints, solvents, fertilizers and pesticides. Once the required usage pattern is determined, the in-house inventory should be limited to only the amount required for a reasonable time period. Minimizing stock on-hand also minimizes waste disposal problems associated with leakage, spillage and degradation of stored products.

Within experimental operations, good housekeeping might involve careful estimation of future required amounts of chemicals, limiting amounts to those necessary for operation of teaching or research laboratories for an academic term or 6 to 12 month periods. Chemical storage within individual laboratories can be minimized through routine use of the chemical supply service provided by CLS.

  • All organizations and individuals within HKUST who use chemicals can assist in the waste minimization effort through regular and complete inventory procedures so that CLS can keep records of consumption of common or high use chemicals and thereby keep adequate stocks on hand for filling orders with the University.

Substitute less toxic materials

Frequently, a nontoxic material can be substituted for one that is toxic or one that creates a special waste treatment/disposal problem. The reduced cost of disposal or the reduced exposure of students or workers to a toxic material can readily justify the change.

Charge costs required for hazardous waste disposal back to the originating organization or staff or faculty member.

During the early operation stage of the Tsing Yi Island Waste Management Facility, no cost was assessed to waste generators. By design, this practice is changing and generators will be responsible for the cost of waste disposal in the future. Therefore, it pays to minimize the volume of waste generated now so as not to pay expensive disposal fees later.


Recycling of products that have completed a life cycle of use is a means to reduce depletion of natural resources and to reduce dependence on landfill of solid waste. Both of these achievements have economic value and ultimately provide benefit to the community in terms of aesthetics, reduced pressure on limited resources and even to reduce inflation costs as these limitations increasingly affect raw material supplies for our crowded planet. HKUST has begun a recycling program for faculty and staff at campus quarters that includes newspaper and cans. HSEO will continue to expand recycling for other materials as sources are identified in this geographic region who will accept and use the materials collected.

For further information:

  • Please visit the Website of the HKUST Health, Safety & Environment Office for more information regarding environmental protection at HKUST.

  • Please visit the Website of the Environmental Protection Department, HKSAR for the details of Environmental Legislation, Compliance Guides, Enforcement, Environmental Standards & Guidelines.