A useful laboratory fume hood specification does more than name a width and a hood type. It explains the work to be controlled, the room and building interfaces, the required services, the operating expectations and the evidence needed before approval.
When these inputs are missing, suppliers may make different assumptions. One quotation may include an exhaust fan and controls while another may cover only the enclosure. One proposal may be based on a defined chemical list while another may assume general laboratory use. The prices are then difficult to compare because the scopes are not equivalent.
The project team should prepare a short, structured requirement package before requesting a quotation. The final hood selection and performance criteria must still be reviewed by the responsible laboratory safety and engineering teams.
Begin with the process and hazard information
Describe the work before describing the equipment. For each planned process, record:
- The chemical names and, where available, identifying numbers.
- Concentrations, physical forms and maximum quantities used at one time.
- Frequency and duration of work.
- Operating temperatures and whether heating, mixing, spraying or reactions occur.
- Expected vapors, gases, aerosols, dusts, heat or reaction products.
- Whether the chemical program is stable or likely to change.
- The people responsible for hazard assessment and final approval.
Broad labels such as “solvents,” “acids” or “routine chemistry” are not enough for a technical selection. The same chemical can create different requirements when concentration, temperature, quantity or process conditions change.
Do not use the RFQ to replace the laboratory’s risk assessment. The supplier can review product and project information, but the facility must define the hazards, operating controls and applicable requirements.
Treat the hood type as a reviewed decision
If the project has already selected a ducted, filtered or other configuration, state who made that decision and which evidence supports it. If the selection is still open, ask suppliers to identify their proposed approach and the assumptions behind it.
The existing ducted versus ductless fume hood guide provides a high-level comparison. The project specification should go further by documenting the actual chemical scope, building conditions, monitoring requirements and change-control process.
For a filtered or ductless proposal, request a written application review for the planned chemicals and conditions. For a ducted proposal, request the building exhaust, fan, duct, discharge and room-air interfaces that must be supplied or coordinated by others.
Neither configuration is automatically suitable for every process. Avoid accepting a proposal that relies only on purchase price, cabinet size or the presence of a filter.
Define the work zone and physical interface
Provide a scaled room plan and the intended hood location. The specification should identify:
- Required internal work area and the equipment that must fit inside.
- Work surface, sink, cup sink or service-fixture needs.
- Maximum equipment dimensions and operating weight.
- Access needed for setup, cleaning, inspection and removal.
- Doorways, elevators, corridors and delivery restrictions.
- Adjacent benches, cabinets, doors, windows and frequently used equipment.
- Available wall, floor and ceiling interfaces.
Avoid using a nominal hood width as the only dimensional requirement. External size, internal workspace, service zones, sash opening and maintenance access can differ between configurations.
The project team should also confirm whether equipment inside the hood may disturb the intended airflow pattern or block access to controls and services. This requires engineering review for the proposed arrangement.
Specify materials from the real exposure
List the substances, temperatures, cleaning agents and expected spill conditions that may contact the hood interior, work surface, service fixtures and duct connection.
Ask the supplier to identify the proposed materials for the liner, work surface, sash, frame, fittings and other exposed components. Material suitability should be confirmed against the actual exposure rather than a broad claim such as “chemical resistant.”
Where the project has special hygiene, contamination-control or cleaning requirements, describe the required access, joints, penetrations and maintenance conditions. Do not add material performance, temperature limits or compatibility claims to the final specification without current technical evidence for the selected model.
Separate hood scope from building exhaust scope
For a ducted system, clearly assign responsibility for:
- Exhaust ductwork and compatible materials.
- Fan selection, location, support and access.
- Exhaust discharge location and coordination.
- Make-up air and room pressure strategy.
- Dampers, controls and any variable-air-volume interface.
- Roof, wall, structural and weatherproofing work.
- Electrical power and emergency behavior.
- Testing, commissioning and balancing.
The hood enclosure cannot be reviewed in isolation from the exhaust system and room. The responsible mechanical and safety teams must define the required performance criteria and acceptance method.
For a filtered system, identify room ventilation, return-air acceptance, filter access, monitoring, replacement and disposal responsibilities. “No external duct” must not be interpreted as “no room or engineering coordination.”
Describe sash, controls and monitoring requirements
State the operating concept rather than listing features without context. The RFQ should identify:
- The intended sash configuration and normal operating position.
- Whether sash-position sensing or indication is required.
- Which operating condition must be monitored.
- Required local indicators, alarms and reset behavior.
- Whether the hood must interface with room controls or a building management system.
- What should happen after power loss, fan failure or another defined fault.
- Which settings are user-accessible and which require authorized service access.
Do not insert universal alarm points, airflow values or sash limits unless the project engineer has approved them for the selected system and applicable requirements.
Record utilities and service fixtures
List every required service and its source. These may include electrical power, data, water, drainage, gases, vacuum or other project services. For each service, identify:
- The number and intended use of outlets or fixtures.
- The connection point and interface responsibility.
- Required materials or compatibility conditions.
- Isolation and maintenance access.
- Any restrictions on routing through or near the hood.
The room plan should show where these services enter the hood and how they relate to equipment, storage and user reach. Final utility design remains a project engineering responsibility.
Define documentation and acceptance deliverables
Quotations should state which documents are included and when they will be provided. Depending on the project, the review package may need:
- Product data and proposed configuration.
- General arrangement and interface drawings.
- Material information.
- Electrical and control requirements.
- Exhaust or filtration interface information.
- Operation and maintenance instructions.
- Inspection, testing or commissioning documentation.
- Spare-parts and consumables information.
- Model-specific standards, reports or certifications requested by the project.
Do not assume a standard, test report or certification applies to every model or destination. Request current documents for the exact configuration and confirm their scope before including them in a project submittal.
Make exclusions and responsibilities visible
Every quotation should identify what is included, excluded and supplied by others. Ask suppliers to state assumptions for exhaust, fan, ductwork, controls, room ventilation, utilities, installation, testing, training, filters, consumables and disposal.
If two proposals use different assumptions, normalize the scope before comparing price. A lower quotation may simply exclude building work, documentation or services included elsewhere.
Use a comparable RFQ schedule
Create one schedule for all bidders with the same fields:
| Requirement area | Information to provide |
|---|---|
| Process | Activities, chemicals, quantities, temperatures and frequency |
| Hood | Proposed type, internal workspace and configuration |
| Materials | Liner, work surface, sash, frame and exposed fixtures |
| Building | Room plan, exhaust, make-up air, discharge and pressure interfaces |
| Controls | Sash concept, indicators, alarms, interlocks and BMS interface |
| Utilities | Power, water, drainage, gases, data and connection responsibility |
| Access | Delivery, installation, cleaning, inspection and maintenance clearances |
| Documentation | Drawings, manuals, technical evidence, testing and commissioning |
| Scope | Inclusions, exclusions, assumptions and items supplied by others |
This structure helps the project team compare technical scope before comparing price.
Prepare the final review package
Before releasing the purchase order, confirm that the process information, room design, hood configuration, exhaust or filtration strategy, controls, utilities and acceptance requirements agree with one another.
Review the available laboratory fume hood configurations and send the project team the chemical list, room plan, equipment schedule and building conditions. A technical discussion can then identify which information is complete, which items need engineering coordination and which model-specific claims require current documentation.
CTA: Request a fume hood technical review with your chemical list, room drawing, equipment schedule and exhaust conditions.