A waste audit is a structured process where you collect, sort, and weigh the trash your facility produces to find out exactly what’s being thrown away and how much of it could be diverted. The process typically involves three approaches: examining your waste hauling records, walking through your facility to observe disposal habits, and physically sorting through collected waste. Most organizations can complete a basic audit in one to two weeks from planning to final report.
Define Your Goals and Scope
Before touching a single bag of trash, decide what you want to learn. Are you trying to reduce disposal costs? Increase your recycling rate? Meet a sustainability commitment? Your goal shapes every decision that follows, from which waste streams you examine to how many days of trash you collect.
Decide whether you’re auditing the entire facility or specific departments. If your building has a cafeteria, office floors, and a warehouse, each generates very different waste. Auditing them separately gives you targeted data. If you’re sampling from multiple locations, plan a labeling system now. You can tag bags with stickers or colored twist ties by department, or use different colored garbage bags in each area so they’re easy to distinguish on sorting day.
Set Up Your Sorting Location and Supplies
You need a flat, covered area large enough to spread out waste and move around it safely. A loading dock, parking area under a canopy, or a large indoor space with good ventilation all work. Lay down a tarp to contain liquids and small debris, and set up a sorting table if possible.
Your supply list should include:
- Scale: A platform or floor scale that can handle full bags (a bathroom scale works for smaller audits, but not a kitchen scale).
- Labeled sorting containers: Bins, buckets, or bags for each waste category you’re tracking.
- Tarp: To protect your sorting surface and make cleanup easier.
- Data recording sheets: Pre-built spreadsheets or printed forms with your waste categories and space for weights.
- Gloves, closed-toe shoes, and eye protection: At minimum. If you’re sorting commercial or institutional waste that could contain sharp objects, broken glass, or chemical residues, add puncture-resistant gloves and a dust mask.
For personal protective equipment, OSHA guidelines are straightforward: assess the hazards present and select gear that matches. For most office or school waste audits, heavy-duty rubber gloves and safety glasses are sufficient. For restaurant, manufacturing, or mixed-use facility waste, consider thicker gloves rated for puncture resistance, long sleeves, and respiratory protection if you expect dust or fumes. Make sure everyone on the sorting team knows how to properly wear their gear and understands its limitations before sorting begins.
Coordinate With Staff Before Collection
A waste audit only works if the waste you collect reflects normal operations. If employees know their trash is being examined and change their habits, your data won’t be useful. Keep communication focused on logistics rather than behavior. Let people know that trash pickup schedules may change temporarily, but avoid creating anxiety about what’s in the bins.
Janitorial and maintenance staff are your most important partners. Ask them to collect and set aside waste from your target areas over the course of a few days so that nothing enters the dumpster or compactor before you can sort it. Brief them on the altered routine: where to store bags, how to label them, and how long the collection period will last. If your facility uses a waste hauler, you may also need to coordinate a temporary hold on pickups or arrange for extra storage containers.
Choose Your Waste Categories
The categories you track depend on your facility type and goals, but a standard set covers most situations: paper and cardboard, plastics (broken out by type if you want granular data), glass, metals, food waste and organics, textiles, electronics, and a catch-all category for everything else. For context, paper has historically been the largest component of municipal solid waste in the U.S., making up about 23% of all generated trash. That number gives you a rough benchmark, though your facility’s breakdown will depend heavily on what kind of work happens there.
Label your sorting containers clearly with both the category name and examples of what goes in each. “Paper” is vague. “Paper: office paper, newspaper, magazines, junk mail, shredded paper” prevents confusion during a fast-paced sort. Add a container specifically for items that could have been recycled or composted but ended up in the trash. This “misplaced” category is often the most valuable finding in the entire audit.
Collect and Sort the Waste
Collect waste over a period that represents normal operations. A single day’s trash can be skewed by unusual events like a catered lunch or a supply delivery. Two to five days of collection gives you a more reliable picture. Avoid weeks with holidays, special events, or unusually high or low occupancy.
On sorting day, assemble your team and run a brief training session. Cover the purpose of the audit, how to sort materials into each category, and the safety plan. Designate a field supervisor whose job is to keep the sort consistent and to flag anything potentially hazardous. Needles, batteries, chemical containers, or anything that looks like it could cause injury should be set aside immediately and handled separately.
Open bags onto the tarped sorting surface and work through the contents methodically. Sort each item into the correct labeled container. This is slow, unglamorous work, and it helps to have at least three or four people so sorters can rotate and stay focused. Expect the process to take roughly 30 minutes to an hour per large bag, depending on how mixed the waste is.
Weigh and Record Everything
Once a sorting container is full or a bag’s contents have been fully separated, weigh each category. Subtract the weight of the empty container first. Record the weight on your data sheet along with the source location, date, and any notes about unusual items.
Calculate each category as a percentage of total weight. This is the core of your audit data. You want to know, for example, that 35% of your waste by weight is food scraps, 20% is recyclable paper that wasn’t recycled, and 15% is single-use plastics. Volume matters too, since lightweight materials like plastic bags and foam take up enormous space in a dumpster even though they weigh little. If dumpster capacity is a cost driver for your facility, note the volume of each category alongside its weight.
Analyze Results and Identify Priorities
Your sorted, weighed data tells you two things: what your facility throws away, and how much of it didn’t need to be thrown away. The most actionable finding is usually the percentage of waste that was recyclable or compostable but ended up in the trash. This is your diversion opportunity, the gap between what you’re doing and what you could be doing without changing purchasing habits at all.
Compare your results against your own goals and against available benchmarks. The EPA estimated total U.S. municipal solid waste generation at about 292 million tons in its most recent comprehensive data. Your per-employee or per-square-foot waste generation rate can be compared year over year to track progress, and industry associations for sectors like hospitality, healthcare, or higher education often publish sector-specific benchmarks.
Look for the biggest opportunities first. If food waste is your largest category and you don’t have a composting program, that’s where to start. If recyclable paper and cardboard make up a significant share of your landfill waste, the fix might be as simple as adding clearly labeled recycling bins in the right locations. Prioritize changes by the combination of impact (how much waste they’d divert) and feasibility (how easy they are to implement).
Build Your Action Plan
A waste audit without follow-through is just a messy afternoon. Translate your findings into specific, scheduled actions. For each priority area, document the current state (what’s happening now and how much waste it produces), the target state (what you want to change), the action required, who’s responsible, and a timeline.
Common actions that come out of waste audits include renegotiating hauling contracts based on actual volume data, adding recycling or composting infrastructure, switching purchasing to reduce packaging, and training staff on proper sorting. Some changes are free. Putting a recycling bin next to every trash can costs almost nothing but can dramatically shift how much recyclable material actually gets recycled.
Plan to repeat the audit on a regular schedule, typically annually or semi-annually. Your first audit establishes the baseline. Every audit after that measures whether your changes are working. Keep your methodology consistent between audits so the data is comparable: same collection period length, same categories, same sorting process. Over time, this creates a clear record of progress that justifies continued investment in waste reduction.