Storage Equipment - Technology and Practices (ASHRAE TC 9.9 Storage White Paper)

Overview

The document treats three storage media, disk, flash and tape, separately for technology and environmental sensitivity. Non-operational time limits and reliability considerations differ per medium, so a single room setpoint does not carry the same risk for all storage equipment. On airflow, ASHRAE recommends front-to-back cooling for storage arrays and asks storage OEMs for more granular airflow data. Each medium therefore has its own tolerance to temperature, humidity and idle storage.

Equipment that draws from the side or rear can recirculate hot air in contained-aisle layouts, so airflow direction should be treated as a design attribute. The multi-zone approach is the heart of its energy-saving recommendations. Tape needs a stable environment similar to Class A1: roughly 15-32 degC, 20-80% RH and less than 5 degC per hour of change. Narrowing the tape zone raises cooling cost only for that zone.

If the tape zone is held to that narrow envelope, the compute area can run in the wider A2/A3 range and gain economiser hours. It is a free white paper without product-level measurements or a cost model; recommendations rest on the ASHRAE Thermal Guidelines framework. Its main contribution is showing that storage is not a room-wide class driver but a constraint that zoning can solve.

Key points

1. ASHRAE recommends front-to-back cooling airflow for storage arrays.
2. Tape needs a stable environment similar to Class A1: about 15-32 degC, 20-80% RH, under 5 degC/h change.
3. Multiple environmental zones are recommended in a data center (for example a separate tape zone).
4. Storage OEMs are asked for more granular airflow data.
5. Non-operational time limits and reliability are discussed separately for each storage medium.

Using it in design

• In the zone model, define a thermal class per zone instead of one room setpoint (for example tape room A1/narrow, compute A2/A3).
• Add an airflow-direction attribute (F2B, B2F, side) to the rack catalog.
• Warn on non-F2B equipment placed in contained aisles.
• Add a control rule keeping the tape zone's rate of temperature change under 5 degC/h.

Who should read it

Thermal designers and infrastructure architects planning storage and tape equipment alongside economiser or warm-environment strategies.

Related standards

• ASHRAE Thermal Guidelines for Data Processing Environments

Publication details

Authors

ASHRAE TC 9.9

Publisher

ASHRAE TC 9.9

Year

2015

Document number

TC 9.9 White Paper

Document language

English

Source type

Standard

Access

Free to read

Licence

Copyright retained; citation only — the publisher’s terms apply to the original document

Citation