diff --git a/packages/common/mod.ts b/packages/common/mod.ts
index b93334c7b..8caf5ac1e 100644
--- a/packages/common/mod.ts
+++ b/packages/common/mod.ts
@@ -34,6 +34,7 @@ export {
   hexToBytes,
   i2Osp,
   isCryptoKeyPair,
+  isDenoV1,
   isNode,
   kemToKeyGenAlgorithm,
   loadCrypto,
diff --git a/packages/common/src/utils/misc.ts b/packages/common/src/utils/misc.ts
index eba0f3f44..d368ec056 100644
--- a/packages/common/src/utils/misc.ts
+++ b/packages/common/src/utils/misc.ts
@@ -1,5 +1,9 @@
 import { KemId } from "../identifiers.ts";
 
+export const isDenoV1 = (): boolean =>
+  // deno-lint-ignore no-explicit-any
+  (globalThis as any).process === undefined;
+
 export function isNode(): boolean {
   // deno-lint-ignore no-explicit-any
   if ((globalThis as any).process === undefined) {
diff --git a/packages/hpke-js/test/conformance.test.ts b/packages/hpke-js/test/conformance.test.ts
index ca933d55c..57f691552 100644
--- a/packages/hpke-js/test/conformance.test.ts
+++ b/packages/hpke-js/test/conformance.test.ts
@@ -1,6 +1,6 @@
 import { afterAll, beforeAll, describe, it } from "@std/testing/bdd";
 
-import { isNode } from "@hpke/common";
+import { isDenoV1, isNode } from "@hpke/common";
 
 import type { ConformanceTester } from "./conformanceTester.ts";
 import type { TestVector } from "./testVector.ts";
@@ -30,7 +30,7 @@ describe("RFC9180 conformance", () => {
     it("should match demonstrated values", async () => {
       for (const v of testVectors) {
         if (v.mode === 0 && v.kem_id === 0x0010 && v.aead_id <= 0x0002) {
-          if (!isNode()) {
+          if (isDenoV1()) {
             continue;
           }
           await tester.test(v);
@@ -66,7 +66,7 @@ describe("RFC9180 conformance", () => {
     it("should match demonstrated values", async () => {
       for (const v of testVectors) {
         if (v.mode === 0 && v.kem_id < 0x0020 && v.aead_id === 0x0003) {
-          if (!isNode()) {
+          if (v.kem_id === 0x0012 && !isNode()) {
             continue;
           }
           await tester.test(v);
@@ -79,7 +79,7 @@ describe("RFC9180 conformance", () => {
     it("should match demonstrated values", async () => {
       for (const v of testVectors) {
         if (v.mode === 0 && v.kem_id < 0x0020 && v.aead_id === 0xFFFF) {
-          if (!isNode()) {
+          if (v.kem_id === 0x0012 && !isNode()) {
             continue;
           }
           await tester.test(v);
@@ -152,7 +152,7 @@ describe("RFC9180 conformance", () => {
     it("should match demonstrated values", async () => {
       for (const v of testVectors) {
         if (v.mode === 1 && v.kem_id < 0x0020 && v.aead_id <= 0x0002) {
-          if (!isNode()) {
+          if (v.kem_id === 0x0012 && !isNode()) {
             continue;
           }
           await tester.test(v);
@@ -165,7 +165,7 @@ describe("RFC9180 conformance", () => {
     it("should match demonstrated values", async () => {
       for (const v of testVectors) {
         if (v.mode === 1 && v.kem_id < 0x0020 && v.aead_id === 0x0003) {
-          if (!isNode()) {
+          if (v.kem_id === 0x0012 && !isNode()) {
             continue;
           }
           await tester.test(v);
@@ -178,7 +178,7 @@ describe("RFC9180 conformance", () => {
     it("should match demonstrated values", async () => {
       for (const v of testVectors) {
         if (v.mode === 1 && v.kem_id < 0x0020 && v.aead_id === 0xFFFF) {
-          if (!isNode()) {
+          if (v.kem_id === 0x0012 && !isNode()) {
             continue;
           }
           await tester.test(v);
@@ -251,7 +251,7 @@ describe("RFC9180 conformance", () => {
     it("should match demonstrated values", async () => {
       for (const v of testVectors) {
         if (v.mode === 2 && v.kem_id < 0x0020 && v.aead_id <= 0x0002) {
-          if (!isNode()) {
+          if (v.kem_id === 0x0012 && !isNode()) {
             continue;
           }
           await tester.test(v);
@@ -264,7 +264,7 @@ describe("RFC9180 conformance", () => {
     it("should match demonstrated values", async () => {
       for (const v of testVectors) {
         if (v.mode === 2 && v.kem_id < 0x0020 && v.aead_id === 0x0003) {
-          if (!isNode()) {
+          if (v.kem_id === 0x0012 && !isNode()) {
             continue;
           }
           await tester.test(v);
@@ -277,7 +277,7 @@ describe("RFC9180 conformance", () => {
     it("should match demonstrated values", async () => {
       for (const v of testVectors) {
         if (v.mode === 2 && v.kem_id < 0x0020 && v.aead_id === 0xFFFF) {
-          if (!isNode()) {
+          if (v.kem_id === 0x0012 && !isNode()) {
             continue;
           }
           await tester.test(v);
@@ -350,7 +350,7 @@ describe("RFC9180 conformance", () => {
     it("should match demonstrated values", async () => {
       for (const v of testVectors) {
         if (v.mode === 3 && v.kem_id < 0x0020 && v.aead_id <= 0x0002) {
-          if (!isNode()) {
+          if (v.kem_id === 0x0012 && !isNode()) {
             continue;
           }
           await tester.test(v);
@@ -363,7 +363,7 @@ describe("RFC9180 conformance", () => {
     it("should match demonstrated values", async () => {
       for (const v of testVectors) {
         if (v.mode === 3 && v.kem_id < 0x0020 && v.aead_id === 0x0003) {
-          if (!isNode()) {
+          if (v.kem_id === 0x0012 && !isNode()) {
             continue;
           }
           await tester.test(v);
@@ -376,7 +376,7 @@ describe("RFC9180 conformance", () => {
     it("should match demonstrated values", async () => {
       for (const v of testVectors) {
         if (v.mode === 3 && v.kem_id < 0x0020 && v.aead_id === 0xFFFF) {
-          if (!isNode()) {
+          if (v.kem_id === 0x0012 && !isNode()) {
             continue;
           }
           await tester.test(v);