Workshop Maintenance

                   Combined Cleaning and Mopping Instructions and Spills Appendix

                                            Thayer School Machine Shop

How to Mop the Floor, a Step-by-Step Guide

Machine shops have a high potential to impact a watershed with contaminants. These contaminants can damage sensitive habitats and eventually pollute our water supply. Implementing best management practices can drastically reduce environmental impacts from machine
shops. This instruction guide has been prepared to familiarize machine shop staff with the best management practices for proper floor cleaning and dealing with typical wastes generated in the shop.

No metal chips or material shavings may be discharged with floor wash water into drains after mopping the shop floor. You must filter metal chips and shavings from detergent/water before discharging soapy water into the drain.

The procedure for mopping up spills differs from the process of mopping the floor for routine cleaning. When cleaning up spilled coolant, oil, or solvents, care must be taken to prevent these fluids from being discharged into sink drains. The procedure for cleaning spills is described in the Appendix of this document.**

Step 1: Locate supplies**
You should find the mop bucket (yellow) and mop (in sink) in the cleaning closet in the rear of the shop.

Step 2: Fill bucket with cleaning solution
Empty 2 packets of cleaner/degreaser into the mop bucket. Fill the bucket (appx 4 gal) with warm/hot water.

Step 3: Clear area of obstructions
Remove any obstructions that prohibit proper mopping. Your working area should be around 15 square feet (5 feet x 3 feet).

Step 4: Prepare mop
Locate the mop bucket close to the working area.

Remove the mop from the bucket and place it into the wringer. Place your hand on the handle and apply liberal downward force to squeeze excess cleaning solution out of the mop. You may have to do this several times, rotating the mop each time to remove all of the excess solution. When finished, the mop should only be damp.

Step 5: Start mopping
Starting in the farthest corner, use a side‐to‐side motion to thoroughly clean the entirety of the floor. Here, an effect “S” pattern is used to maximum coverage and minimize overlap. Once your area is thoroughly cleaned, move the mop bucket towards your exit, creating a new working area. Continue mopping with a side‐to‐side motion in the new working area. Ensure that you reach into all corners.

When finished, the floor should have a wet look, but there should not be any puddles or excessively wet spots.

Step 6: Wrapping up
Mop waste water must be filtered to prevent metal particles and debris from entering the water stream. The mop sink is equipped with a basin strainer which is covered with a disposable cloth filter. Empty the mop bucket water through the cloth filter and strainer. Return the mop bucket to its original location. Periodically replace the cloth filter. Dispose the spent filter in the machine shop solid waste bin.

Hazardous Waste Management
The procedure for mopping up spills differs from the process of mopping the floor for routine cleaning. This appendix has been prepared to familiarize machine shop staff with the best management practices for managing spills.

Machine shop solvents, lubricants, coolants and other working fluids are hazardous and must not be permitted to contaminate ground water and potentially damage sensitive habitats. If these materials are discharged onto the shop floor, the event is referred to as a “spill” and care must be taken to prevent them from entering the water supply. These materials must be
removed with a spill kit and the kit contents must be disposed of by the Dartmouth College Environmental Health and Safety office (EHS).

Spill events should be rare events, and the final step in the clean-up and disposal process is to identify the root cause of the spill and to prepare a written plan to prevent a recurrence of the event which produced the spill.
Spill kits includes:

• Absorbents (mats, socks, and loose) • Containment dikes • Personal
protective equipment (PPE) such as goggles, gloves, suits or aprons and booties • Bags to collect and hold spent spill cleanup materials.

Process for spill cleanup

For most machine shop spills, cleaning up lubricants, cutting fluids, coolants or shop solvents involving spills of 5 gal or less. 

Retrieve the spill kit mounted on the shop wall near the custodial closet and
bring it to the spill site.

Then execute the following:
1) Protect Use appropriate personal protective equipment – nitrile gloves and safety glasses at minimum – and other equipment as necessary.

2) Confine Surround the spill with adsorbent socks to prevent the expansion of the spill area.
3) Cleanup Use adsorbent pads from the kit to soak up the fluid and deposit these in the spill kit pail Prepare a hazardous waste label and affix this to
the lid of the pail containing the saturated pads
4) Dispose Deliver the complete spill kit with affixed label to the machine shop Hazardous Waste Collection Cabinet and email for waste pickup.