Philips Alto F48T8/TL841/HO/ALTO 44W T8 High Output Fluorescent Lamp – 4100K Cool White | 4000 Lumens | CRI 86 | R17d Base | 48-Inch

The Philips Alto F48T8/TL841/HO/ALTO is a 44-watt high-output T8 fluorescent lamp delivering 4,000 initial lumens at 4100K with a CRI of 86 — producing more light than standard 32W T8 lamps in the same fixture footprint. The R17d recessed double-contact base is the standard configuration for T8 high-output applications. Trichromatic phosphors, Philips lowest-level mercury Alto technology, and over 95 lumens per watt efficacy make this lamp a premium specification for commercial, industrial, and retrofit lighting projects requiring elevated light output with high color quality.

Quick Specs

• Brand: Philips
• Series: Alto
• Lamp Code: F48T8/TL841/HO/ALTO
• Lamp Type: T8 High Output Linear Fluorescent
• Wattage: 44W
• Color Temperature: 4100K (Cool White — TL841)
• CRI: 86
• Initial Lumens: 4,000 lm
• Mean Lumens: 3,600 lm
• Lamp Efficacy: >95 lumens per watt
• Rated Average Life: 18,000 hours
• Base: R17d Recessed Double Contact (Black)
• Overall Length (MOL): 48 inches
• Diameter: 1 inch (T8)
• Phosphor Technology: Trichromatic
• Mercury Technology: Philips Alto — Lowest-Level Mercury

Product Overview

The Philips Alto F48T8/TL841/HO/ALTO is a 44-watt T8 high-output fluorescent lamp — producing 4,000 initial lumens from the same 48-inch T8 form factor as a standard 32W T8, but at significantly higher output per lamp. The high-output designation means this lamp requires a T8HO ballast and uses an R17d recessed double-contact base rather than the standard G13 bi-pin found on regular T8 lamps. Buyers replacing or specifying this lamp must confirm their fixture and ballast are rated for T8 high-output operation.

CRI 86 is the defining quality specification that separates the Alto F48T8/TL841/HO from lower-grade 700-series T8 alternatives. At CRI 86, trichromatic phosphors produce accurate, vivid color rendering across the full 4100K cool white spectrum — appropriate for retail display, food service, precision manufacturing, and healthcare environments where color quality directly affects product presentation or clinical accuracy.

Philips Alto technology applies the industry’s lowest mercury content at the manufacturing stage — addressing both regulatory compliance and environmental impact before end-of-life disposal. Lamp efficacy exceeds 95 lumens per watt, and trichromatic phosphors deliver improved lumen maintenance over the 18,000-hour rated life compared to standard halophosphate lamps.

Why Choose This Product

• 4,000 initial lumens — high-output T8 performance: Delivers 4,000 lm from a 48-inch T8 lamp at 44W — approximately 43% more light output than a standard 32W T8 at 2,800 lm in the same fixture position.
• CRI 86 — high color rendering quality: Trichromatic phosphors deliver accurate color at CRI 86, well above the CRI 78 of standard 700-series T8 lamps — appropriate for retail, food service, healthcare, and precision environments where color quality matters.
• >95 lumens per watt efficacy: Competitive high-output efficacy for the 44W T8 category — elevated light output with controlled energy consumption.
• Philips Alto lowest-level mercury technology: Reduced mercury at the manufacturing stage — supports environmental compliance programs and minimizes disposal risk across the lamp’s service life.
• Trichromatic phosphors with improved lumen maintenance: Slower lumen depreciation compared to halophosphate lamps means consistent light levels are maintained longer across the 18,000-hour rated life.
• 50% longer life vs. standard fluorescent: 18,000-hour rating reduces replacement frequency and maintenance labor cost compared to standard 12,000-hour lamps.
• Easy retrofit for T8HO fixture upgrades: R17d base and 48-inch length are the standard for T8HO commercial fixtures — direct replacement in existing T8HO housings.

Technical Specifications

Dimensions

Applications

The Philips Alto F48T8/TL841/HO/ALTO 44W T8HO is specified for commercial and industrial applications where elevated light output and high color rendering are both required:

• Retail display and merchandise lighting – CRI 86 renders product colors accurately under 4100K cool white — appropriate for apparel, food display, cosmetics, and high-end retail where color quality affects purchase decisions.
• Commercial and industrial high-output fixtures – 4,000 lm per lamp reduces the total fixture count needed to meet footcandle targets in warehouses, manufacturing floors, and large commercial spaces.
• Food service and grocery – High CRI cool white output enhances food presentation in refrigerated and open display cases, deli counters, and prepared food areas.
• Healthcare and clinical environments – CRI 86 supports accurate color assessment in examination rooms, procedure areas, and nursing stations where skin tones and specimen colors must be rendered accurately.
• Office and commercial interiors requiring elevated light levels – T8HO fixtures in open-plan offices, conference rooms, and lobby spaces where standard 32W T8 output is insufficient for the design footcandle target.
• T8HO retrofit projects – Direct replacement for existing R17d base T8HO fixtures — reduces mercury content and improves lumen maintenance compared to older halophosphate T8HO lamps.

Replacing Your Current T8 High Output Lamp?

This is a T8 High Output lamp — not a standard T8. Confirm the following before ordering:

• Base type — R17d recessed double contact: This lamp uses an R17d black recessed double-contact base, not the standard G13 medium bi-pin used on regular 32W T8 lamps. Confirm your fixture uses R17d lampholders before ordering. Installing this lamp in a G13 fixture is not possible without lampholder replacement.
• Ballast type — T8HO ballast required: This 44W high-output lamp requires a ballast specifically rated for T8HO lamps. Standard T8 ballasts (rated for 32W) will not correctly drive this lamp. Verify your existing ballast is a T8HO-rated unit before ordering.
• Wattage: 44W — significantly higher than standard 32W T8. Verify your ballast and fixture are rated for 44W T8HO operation.
• CRI comparison: This is a CRI 86 lamp. If your current installation uses standard CRI 75–78 T8HO lamps, this is an upgrade in color rendering quality.
• Fixture length: 48-inch MOL — the standard length for T8HO commercial fixtures. Verify your fixture housing accepts 48-inch lamps.
• Color temperature: 4100K cool white. If replacing 3000K, 3500K, or 5000K T8HO lamps, note the color shift.

Ordering Information

• Brand: Philips
• Lamp Code: F48T8/TL841/HO/ALTO
• Series: Alto
• Lamp Type: T8 High Output, 44W
• Color Temperature: 4100K Cool White
• Base: R17d Recessed Double Contact
• Case quantities and bulk pricing: Contact ADL Supply for volume orders.

Compliance and Certifications

• Philips Alto Low-Mercury Technology: Yes — lowest-level mercury content at manufacturing
• Verify RoHS compliance status with manufacturer specification sheet.
• Verify TCLP compliance with manufacturer specification sheet.
• Verify California Title 20 / T24 compliance with manufacturer specification sheet.
• Verify Prop 65 warning requirements with manufacturer specification sheet.

ADL Supply recommends confirming all applicable compliance data with the Philips official product data sheet prior to specification or installation.