The Vacuum System on the International Space Station is composed of two separate parts: the VRS (Vacuum Resource System) and the VES (Vacuum Exhaust System).

The VRS is for maintaining a vacuum required for conducting science. Many payloads may be actively using the VRS simultaneously.

The VES is for venting a chamber down to vacuum or exhausting hazardous byproducts to space. Only one payload or system may use the VES at a time in order to avoid cross contamination and prevent any chemical reactions occurring between simultaneously vented byproducts.

One of the only payloads that connects to both VES and VRS is MSRR (Materials Science Research Rack), which vents to vacuum using VES and then uses VRS to maintain the vacuum for insulating its furnace which can reach 1400°C.

Many different ISS payloads (science experiments) use the VES to vent byproducts of their experiments to space. This payload complement often changes with each Expedition, but there are some long-running experiment facilities that use VES:

Among those is CIR (Combustion Integrated Rack - pronounced "sir"), which vents combustion byproducts to the VES.

Another is Amine Swingbed, which is an experiment-turned-facility that scrubs CO2 from the ISS cabin atmosphere.

Any payload developers that plan to use the VES system have to provide detailed information of what they'll be venting:

For each mode of operation: Provide a list of vented gases to include the constituent vented, the total mass vented, initial temperature, initial pressure, concentration of the constituent, mass flow rate, frequency and duration of venting operations, and pressure versus time curve at the payload interface.

Source: NASA ISS Pressurized Payloads Interface Requirements Document

Other payloads that use VES but don't have an interface directly to the VES system can use MSG (Microgravity Science Glovebox) to vent. I believe Made In Space's original 3DP experiment was run in MSG. Their later AMF facility does not use VES - they must have incorporated an air filter in that design. (I was an MSFC POIC Operations Controller responsible for managing real-time payloads resources while AMF was/is an active experiment, but 3DP was before my time at NASA.)

The Vacuum System on the International Space Station is composed of two separate parts: the VRS (Vacuum Resource System) and the VES (Vacuum Exhaust System).

The VRS is for maintaining a vacuum required for conducting science. Many payloads may be actively using the VRS simultaneously.

The VES is for venting a chamber down to vacuum or exhausting hazardous byproducts to space. Only one payload or system may use the VES at a time in order to avoid cross contamination and prevent any chemical reactions occurring between simultaneously vented byproducts.

One of the only payloads that connects to both VES and VRS is MSRR (Materials Science Research Rack), which vents to vacuum using VES and then uses VRS to maintain the vacuum for insulating its furnace which can reach 1400°C.

Many different ISS payloads (science experiments) use the VES to vent byproducts of their experiments to space. This payload complement often changes with each Expedition, but there are some long-running experiment facilities that use VES:

Among those is CIR (Combustion Integrated Rack - pronounced "sir"), which vents combustion byproducts to the VES.

Another is Amine Swingbed, which is an experiment-turned-facility that scrubs CO2 from the ISS cabin atmosphere.

Any payload developers that plan to use the VES system have to provide detailed information of what they'll be venting:

For each mode of operation: Provide a list of vented gases to include the constituent vented, the total mass vented, initial temperature, initial pressure, concentration of the constituent, mass flow rate, frequency and duration of venting operations, and pressure versus time curve at the payload interface.

Source: NASA ISS Pressurized Payloads Interface Requirements Document

Other payloads that need to use VES but don't have an interface directly to the VES system can use MSG (Microgravity Science Glovebox) to vent. MSG is also used to contain experiments using hazardous substances. Rodent Research specimen handling is performed in MSG, as are many other biological experiments. Some of the experiments listed in NASA's page for MSG use VES through the glovebox's interface.

I believe Made In Space's original 3DP experiment was run in MSG. Their later AMF facility does not use VES - they must have incorporated an air filter in that design. (I was an MSFC POIC Operations Controller responsible for managing real-time payloads resources while AMF was/is an active experiment, but 3DP was before my time at NASA.)